Plants

14 pages, 1990 KiB

Open AccessEditor’s ChoiceArticle

Application of Deep Eutectic Solvents for the Extraction of Rutin and Rosmarinic Acid from Satureja montana L. and Evaluation of the Extracts Antiradical Activity

by Martina Jakovljević, Jelena Vladić, Senka Vidović, Kristian Pastor, Stela Jokić, Maja Molnar and Igor Jerković

Plants 2020, 9(2), 153; https://doi.org/10.3390/plants9020153 - 26 Jan 2020

Cited by 28 | Viewed by 5028

Abstract

Satureja montana L. was used in the current research as the plant exhibits numerous health-promoting benefits due to its specific chemical composition. The extraction method based on deep eutectic solvents (DESs) was used for the extraction of rutin and rosmarinic acid from this [...] Read more.

Satureja montana L. was used in the current research as the plant exhibits numerous health-promoting benefits due to its specific chemical composition. The extraction method based on deep eutectic solvents (DESs) was used for the extraction of rutin and rosmarinic acid from this plant. Five different choline chloride-based DESs with different volumes of water (10%, 30%, and 50% (v/v)) were used for the extraction at different temperatures (30, 50, and 70 °C) to investigate the influence on rosmarinic acid and rutin content obtained by high-performance liquid chromatography with diode-array detector (HPLC-DAD) in the obtained extracts. A principal component analysis was employed to explore and visualize the influence of applied parameters on the efficiency of the extraction procedure of rutin and rosmarinic acid. Among the tested DESs, choline chloride:lactic acid (mole ratio 1:2) and choline chloride:levulinic acid (mole ratio 1:2) were the most suitable for the extraction of rutin, while for rosmarinic acid choline chloride:urea (mole ratio 1:2) was the most effective solvent. The extract showing the best antiradical activity was obtained with choline chloride:urea (mole ratio 1:1) at 30 °C and 50% H₂O (v/v). Full article

(This article belongs to the Special Issue 2019 Feature Papers by Plants’ Editorial Board Members)

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21 pages, 648 KiB

Open AccessEditor’s ChoiceReview

Transgenesis as a Tool for the Efficient Production of Selected Secondary Metabolites from Plant in Vitro Cultures

by Tomasz Kowalczyk, Joanna Wieczfinska, Ewa Skała, Tomasz Śliwiński and Przemysław Sitarek

Plants 2020, 9(2), 132; https://doi.org/10.3390/plants9020132 - 21 Jan 2020

Cited by 28 | Viewed by 8470

Abstract

The plant kingdom abounds in countless species with potential medical uses. Many of them contain valuable secondary metabolites belonging to different classes and demonstrating anticancer, anti-inflammatory, antioxidant, antimicrobial or antidiabetic properties. Many of these metabolites, e.g., paclitaxel, vinblastine, betulinic acid, chlorogenic acid or [...] Read more.

The plant kingdom abounds in countless species with potential medical uses. Many of them contain valuable secondary metabolites belonging to different classes and demonstrating anticancer, anti-inflammatory, antioxidant, antimicrobial or antidiabetic properties. Many of these metabolites, e.g., paclitaxel, vinblastine, betulinic acid, chlorogenic acid or ferrulic acid, have potential applications in medicine. Additionally, these compounds have many therapeutic and health-promoting properties. The growing demand for these plant secondary metabolites forces the use of new green biotechnology tools to create new, more productive in vitro transgenic plant cultures. These procedures have yielded many promising results, and transgenic cultures have been found to be safe, efficient and cost-effective sources of valuable secondary metabolites for medicine and industry. This review focuses on the use of various in vitro plant culture systems for the production of secondary metabolites. Full article

(This article belongs to the Special Issue Biotechnological Approaches for the Production of Bioactives)

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13 pages, 1424 KiB

Open AccessEditor’s ChoiceArticle

Biostimulant Effect and Biochemical Response in Lettuce Seedlings Treated with A Scenedesmus quadricauda Extract

by Ivana Puglisi, Emanuele La Bella, Ermes Ivan Rovetto, Angela Roberta Lo Piero and Andrea Baglieri

Plants 2020, 9(1), 123; https://doi.org/10.3390/plants9010123 - 18 Jan 2020

Cited by 66 | Viewed by 6222

Abstract

The use of natural biostimulants is becoming an attractive option in order to reduce the use of fertilizer and increase the yield of crops. In particular, algal extracts are suitable candidates as they positively affect plant physiology. Among crops, lettuce often requires the [...] Read more.

The use of natural biostimulants is becoming an attractive option in order to reduce the use of fertilizer and increase the yield of crops. In particular, algal extracts are suitable candidates as they positively affect plant physiology. Among crops, lettuce often requires the use of biostimulants to improve both the quality and quantity of production. The aim of this work is to investigate the potential use of a Scenedesmus quadricauda extract as a biostimulant in order to obtain sustainable cultivation and a reduction in the cost of chemical fertilizers in lettuce cultivation. Therefore, the effect of S. quadricauda extract on lettuce seedlings was explored by evaluating the physiological parameters, chlorophyll, carotenoid, and total protein contents as well as several plant enzymatic activities involved in primary and secondary metabolisms. The experiment was performed by growing plants on inert substrate (pumice) with a 16-h photoperiod, by carrying out two consecutive radical treatments, one week apart, using a concentration of the extract corresponding to 1 mg Corg L⁻¹. Lettuce plants were sampled at 1, 4, and 7 days from the first treatment and 7 days from the second treatment. The results showed that the S. quadricauda extract positively affected the growth of lettuce seedlings, mainly acting at the shoot level, determining an increase in dry matter, chlorophylls, carotenoids, proteins, and influencing the activities of several enzymes involved in the primary metabolism. Full article

(This article belongs to the Section Plant Physiology and Metabolism)

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11 pages, 1419 KiB

Open AccessEditor’s ChoiceReview

Can Inositol Pyrophosphates Inform Strategies for Developing Low Phytate Crops?

by Catherine Freed, Olusegun Adepoju and Glenda Gillaspy

Plants 2020, 9(1), 115; https://doi.org/10.3390/plants9010115 - 17 Jan 2020

Cited by 17 | Viewed by 6189

Abstract

Inositol pyrophosphates (PP-InsPs) are an emerging class of “high-energy” intracellular signaling molecules, containing one or two diphosphate groups attached to an inositol ring, that are connected with phosphate sensing, jasmonate signaling, and inositol hexakisphosphate (InsP₆) storage in plants. While information regarding [...] Read more.

Inositol pyrophosphates (PP-InsPs) are an emerging class of “high-energy” intracellular signaling molecules, containing one or two diphosphate groups attached to an inositol ring, that are connected with phosphate sensing, jasmonate signaling, and inositol hexakisphosphate (InsP₆) storage in plants. While information regarding this new class of signaling molecules in plants is scarce, the enzymes responsible for their synthesis have recently been elucidated. This review focuses on InsP₆ synthesis and its conversion into PP-InsPs, containing seven and eight phosphate groups (InsP₇ and InsP₈). These steps involve two types of enzymes: the ITPKs that phosphorylate InsP₆ to InsP₇, and the PPIP5Ks that phosphorylate InsP₇ to InsP₈. This review also considers the potential roles of PP-InsPs in plant hormone and inorganic phosphate (Pi) signaling, along with an emerging role in bioenergetic homeostasis. PP-InsP synthesis and signaling are important for plant breeders to consider when developing strategies that reduce InsP₆ in plants, as this will likely also reduce PP-InsPs. Thus, this review is primarily intended to bridge the gap between the basic science aspects of PP-InsP synthesis/signaling and breeding/engineering strategies to fortify foods by reducing InsP₆. Full article

(This article belongs to the Special Issue Phytic Acid and Mineral Biofortification Strategies: From Plant Science to Breeding and Biotechnological Approaches)

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24 pages, 867 KiB

Open AccessEditor’s ChoiceReview

Citrus limon (Lemon) Phenomenon—A Review of the Chemistry, Pharmacological Properties, Applications in the Modern Pharmaceutical, Food, and Cosmetics Industries, and Biotechnological Studies

by Marta Klimek-Szczykutowicz, Agnieszka Szopa and Halina Ekiert

Plants 2020, 9(1), 119; https://doi.org/10.3390/plants9010119 - 17 Jan 2020

Cited by 245 | Viewed by 44573

Abstract

This review presents important botanical, chemical and pharmacological characteristics of Citrus limon (lemon)—a species with valuable pharmaceutical, cosmetic and culinary (healthy food) properties. A short description of the genus Citrus is followed by information on the chemical composition, metabolomic studies and biological activities [...] Read more.

This review presents important botanical, chemical and pharmacological characteristics of Citrus limon (lemon)—a species with valuable pharmaceutical, cosmetic and culinary (healthy food) properties. A short description of the genus Citrus is followed by information on the chemical composition, metabolomic studies and biological activities of the main raw materials obtained from C. limon (fruit extract, juice, essential oil). The valuable biological activity of C. limon is determined by its high content of phenolic compounds, mainly flavonoids (e.g., diosmin, hesperidin, limocitrin) and phenolic acids (e.g., ferulic, synapic, p-hydroxybenzoic acids). The essential oil is rich in bioactive monoterpenoids such as D-limonene, β-pinene, γ-terpinene. Recently scientifically proven therapeutic activities of C. limon include anti-inflammatory, antimicrobial, anticancer and antiparasitic activities. The review pays particular attention, with references to published scientific research, to the use of C. limon in the food industry and cosmetology. It also addresses the safety of use and potential phototoxicity of the raw materials. Lastly, the review emphasizes the significance of biotechnological studies on C. limon. Full article

(This article belongs to the Special Issue Advances in Citrus Research)

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18 pages, 1379 KiB

Open AccessEditor’s ChoiceReview

Plant Mitochondrial Carriers: Molecular Gatekeepers That Help to Regulate Plant Central Carbon Metabolism

by M. Rey Toleco, Thomas Naake, Youjun Zhang, Joshua L. Heazlewood and Alisdair R. Fernie

Plants 2020, 9(1), 117; https://doi.org/10.3390/plants9010117 - 17 Jan 2020

Cited by 26 | Viewed by 5795

Abstract

The evolution of membrane-bound organelles among eukaryotes led to a highly compartmentalized metabolism. As a compartment of the central carbon metabolism, mitochondria must be connected to the cytosol by molecular gates that facilitate a myriad of cellular processes. Members of the mitochondrial carrier [...] Read more.

The evolution of membrane-bound organelles among eukaryotes led to a highly compartmentalized metabolism. As a compartment of the central carbon metabolism, mitochondria must be connected to the cytosol by molecular gates that facilitate a myriad of cellular processes. Members of the mitochondrial carrier family function to mediate the transport of metabolites across the impermeable inner mitochondrial membrane and, thus, are potentially crucial for metabolic control and regulation. Here, we focus on members of this family that might impact intracellular central plant carbon metabolism. We summarize and review what is currently known about these transporters from in vitro transport assays and in planta physiological functions, whenever available. From the biochemical and molecular data, we hypothesize how these relevant transporters might play a role in the shuttling of organic acids in the various flux modes of the TCA cycle. Furthermore, we also review relevant mitochondrial carriers that may be vital in mitochondrial oxidative phosphorylation. Lastly, we survey novel experimental approaches that could possibly extend and/or complement the widely accepted proteoliposome reconstitution approach. Full article

(This article belongs to the Special Issue Regulation of Central Carbon and Amino Acid Metabolism in Plants)

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20 pages, 1565 KiB

Open AccessEditor’s ChoiceReview

Silicification of Root Tissues

by Alexander Lux, Zuzana Lukačová, Marek Vaculík, Renáta Švubová, Jana Kohanová, Milan Soukup, Michal Martinka and Boris Bokor

Plants 2020, 9(1), 111; https://doi.org/10.3390/plants9010111 - 15 Jan 2020

Cited by 47 | Viewed by 7399

Abstract

Silicon (Si) is not considered an essential element, however, its tissue concentration can exceed that of many essential elements in several evolutionary distant plant species. Roots take up Si using Si transporters and then translocate it to aboveground organs. In some plant species, [...] Read more.

Silicon (Si) is not considered an essential element, however, its tissue concentration can exceed that of many essential elements in several evolutionary distant plant species. Roots take up Si using Si transporters and then translocate it to aboveground organs. In some plant species, root tissues are also places where a high accumulation of Si can be found. Three basic modes of Si deposition in roots have been identified so far: (1) impregnation of endodermal cell walls (e.g., in cereals, such as Triticum (wheat)); (2) formation of Si-aggregates associated with endodermal cell walls (in the Andropogoneae family, which includes Sorghum and Saccharum (sugarcane)); (3) formation of Si aggregates in “stegmata” cells, which form a sheath around sclerenchyma fibers e.g., in some palm species (Phoenix (date palm)). In addition to these three major and most studied modes of Si deposition in roots, there are also less-known locations, such as deposits in xylem cells and intercellular deposits. In our research, the ontogenesis of individual root cells that accumulate Si is discussed. The documented and expected roles of Si deposition in the root is outlined mostly as a reaction of plants to abiotic and biotic stresses. Full article

(This article belongs to the Special Issue Root Development)

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19 pages, 2753 KiB

Open AccessEditor’s ChoiceArticle

Toxic Effects of Single Antibiotics and Antibiotics in Combination on Germination and Growth of Sinapis alba L.

by Ulrike Timmerer, Lennart Lehmann, Ewald Schnug and Elke Bloem

Plants 2020, 9(1), 107; https://doi.org/10.3390/plants9010107 - 15 Jan 2020

Cited by 23 | Viewed by 7613

Abstract

Antibiotics enter agro-ecosystems via the application of farmyard manure, sewage sludge, animal by-products, or digestates. There are many open questions regarding the behavior of such compounds in the soil like their adsorption, degradation, half-life, and their effects on soil organisms and plants. The [...] Read more.

Antibiotics enter agro-ecosystems via the application of farmyard manure, sewage sludge, animal by-products, or digestates. There are many open questions regarding the behavior of such compounds in the soil like their adsorption, degradation, half-life, and their effects on soil organisms and plants. The impact of antibiotics on the development of antibiotic resistance genes in the environment is regarded as the most important effect that endangers the environment as well as human health. Nevertheless, direct plant toxicity, especially of different antibiotics and heavy metals at the same time, can be of importance as well. In the current study, commercially available phytotoxkits were tested with regard to the toxicity of single antibiotics and antibiotics in combination with the root growth of Sinapis alba L. Additionally, a pot trial was conducted to study the transfer of the observed phytotoxkits results in more complex systems. The phytotoxkits revealed direct toxicity of antibiotics on root development only at high concentrations. The highest toxicity was determined for sulfadiazine, followed by tetracycline and enrofloxacin, showing the least toxicity. When two antibiotics were tested at the same time in the phytotoxkit, synergistic effects were detected. The pot trial indicated lower effect concentrations for enrofloxacin than determined in the phytotoxkit and, therefore, to higher toxicity on plant growth. Full article

(This article belongs to the Section Plant Ecology)

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10 pages, 1539 KiB

Open AccessEditor’s ChoiceArticle

Bioactivity of Common Pesticidal Plants on Fall Armyworm Larvae (Spodoptera frugiperda)

by Kelita Phambala, Yolice Tembo, Trust Kasambala, Vernon H. Kabambe, Philip C. Stevenson and Steven R. Belmain

Plants 2020, 9(1), 112; https://doi.org/10.3390/plants9010112 - 15 Jan 2020

Cited by 43 | Viewed by 8488

Abstract

The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae) is a recent invasive pest species that has successfully established across sub-Saharan Africa where it continues to disrupt agriculture, particularly smallholder cereal production. Management of FAW in its native range in the Americas has led [...] Read more.

The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae) is a recent invasive pest species that has successfully established across sub-Saharan Africa where it continues to disrupt agriculture, particularly smallholder cereal production. Management of FAW in its native range in the Americas has led to the development of resistance to many commercial pesticides before its arrival in Africa. Pesticide use may therefore be ineffective for FAW control in Africa, so new and more sustainable approaches to pest management are required that can help reduce the impact of this exotic pest. Pesticidal plants provide an effective and established approach to pest management in African smallholder farming and recent research has shown that their use can be cost-beneficial and sustainable. In order to optimize the use of botanical extracts for FAW control, we initially screened ten commonly used plant species. In laboratory trials, contact toxicity and feeding bioassays showed differential effects. Some plant species had little to no effect when compared to untreated controls; thus, only the five most promising plant species were selected for more detailed study. In contact toxicity tests, the highest larval mortality was obtained from Nicotiana tabacum (66%) and Lippia javanica (66%). Similarly, in a feeding bioassay L. javanica (62%) and N. tabacum (60%) exhibited high larval mortality at the highest concentration evaluated (10% w/v). Feeding deterrence was evaluated using glass-fibre discs treated with plant extracts, which showed that Cymbopogon citratus (36%) and Azadirachta indica (20%) were the most potent feeding deterrents among the pesticidal plants evaluated. In a screenhouse experiment where living maize plants infested with fall armyworm larvae were treated with plant extracts, N. tabacum and L. javanica were the most potent species at reducing foliar damage compared to the untreated control whilst the synthetic pesticide chlorpyrifos was the most effective in reducing fall armyworm foliar damage. Further field trial evaluation is recommended, particularly involving smallholder maize fields to assess effectiveness across a range of contexts. Full article

(This article belongs to the Special Issue Pesticidal Plants: From Smallholder Use to Commercialisation)

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12 pages, 2547 KiB

Open AccessEditor’s ChoiceArticle

Phytotoxic Activity and Identification of Phytotoxic Substances from Schumannianthus dichotomus

by Md. Mahfuzur Rob, Kawsar Hossen, Arihiro Iwasaki, Kiyotake Suenaga and Hisashi Kato-Noguchi

Plants 2020, 9(1), 102; https://doi.org/10.3390/plants9010102 - 14 Jan 2020

Cited by 39 | Viewed by 6418

Abstract

The phytotoxic potential of plants and their constituents against other plants is being increasingly investigated as a possible alternative to synthetic herbicides to control weeds in crop fields. In this study, we explored the phytotoxicity and phytotoxic substances of Schumannianthus dichotomus, a [...] Read more.

The phytotoxic potential of plants and their constituents against other plants is being increasingly investigated as a possible alternative to synthetic herbicides to control weeds in crop fields. In this study, we explored the phytotoxicity and phytotoxic substances of Schumannianthus dichotomus, a perennial wetland shrub native to Bangladesh, India, and Myanmar. Leaf extracts of S. dichotomus exerted strong phytotoxicity against two dicot species, alfalfa and cress, and two monocot species, barnyard grass and Italian ryegrass. A bioassay-driven purification process yielded two phenolic derivatives, syringic acid and methyl syringate. Both constituents significantly inhibited the growth of cress and Italian ryegrass in a concentration-dependent manner. The concentrations required for 50% growth inhibition (I₅₀ value) of the shoot and root growth of cress were 75.8 and 61.3 μM, respectively, for syringic acid, compared with 43.2 and 31.5 μM, respectively, for methyl syringate. Similarly, to suppress the shoot and root growth of Italian rye grass, a greater amount of syringic acid (I₅₀ = 213.7 and 175.9 μM) was needed than methyl syringate (I₅₀ = 140.4 to 130.8 μM). Methyl syringate showed higher phytotoxic potential than syringic acid, and cress showed higher sensitivity to both substances. This study is the first to report on the phytotoxic potential of S. dichotomus and to identify phytotoxic substances from this plant material. Full article

(This article belongs to the Special Issue Plant Allelopathy and Allelochemicals)

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17 pages, 290 KiB

Open AccessEditor’s ChoiceReview

Current Progress in Nitrogen Fixing Plants and Microbiome Research

by Kishan Mahmud, Shiva Makaju, Razi Ibrahim and Ali Missaoui

Plants 2020, 9(1), 97; https://doi.org/10.3390/plants9010097 - 13 Jan 2020

Cited by 202 | Viewed by 20983

Abstract

In agroecosystems, nitrogen is one of the major nutrients limiting plant growth. To meet the increased nitrogen demand in agriculture, synthetic fertilizers have been used extensively in the latter part of the twentieth century, which have led to environmental challenges such as nitrate [...] Read more.

In agroecosystems, nitrogen is one of the major nutrients limiting plant growth. To meet the increased nitrogen demand in agriculture, synthetic fertilizers have been used extensively in the latter part of the twentieth century, which have led to environmental challenges such as nitrate pollution. Biological nitrogen fixation (BNF) in plants is an essential mechanism for sustainable agricultural production and healthy ecosystem functioning. BNF by legumes and associative, endosymbiotic, and endophytic nitrogen fixation in non-legumes play major roles in reducing the use of synthetic nitrogen fertilizer in agriculture, increased plant nutrient content, and soil health reclamation. This review discusses the process of nitrogen-fixation in plants, nodule formation, the genes involved in plant-rhizobia interaction, and nitrogen-fixing legume and non-legume plants. This review also elaborates on current research efforts involved in transferring nitrogen-fixing mechanisms from legumes to non-legumes, especially to economically important crops such as rice, maize, and wheat at the molecular level and relevant other techniques involving the manipulation of soil microbiome for plant benefits in the non-legume root environment. Full article

(This article belongs to the Section Plant Ecology)

16 pages, 1436 KiB

Open AccessEditor’s ChoiceArticle

Comparison of Organosulfur and Amino Acid Composition between Triploid Onion Allium cornutum Clementi ex Visiani, 1842, and Common Onion Allium cepa L., and Evidences for Antiproliferative Activity of Their Extracts

by Željana Fredotović, Barbara Soldo, Matilda Šprung, Zvonimir Marijanović, Igor Jerković and Jasna Puizina

Plants 2020, 9(1), 98; https://doi.org/10.3390/plants9010098 - 13 Jan 2020

Cited by 30 | Viewed by 4410

Abstract

Species that belong to the genus Allium have been widely used for human food and traditional medicine. Their beneficial health effects, as well as the specific aroma, are associated with their bioactive chemical compounds, such as sulfur compounds and flavonoids. Gas chromatography and [...] Read more.

Species that belong to the genus Allium have been widely used for human food and traditional medicine. Their beneficial health effects, as well as the specific aroma, are associated with their bioactive chemical compounds, such as sulfur compounds and flavonoids. Gas chromatography and mass spectrometry (GC–MS) and reverse-phase high-performance liquid chromatography (reverse-phase HPLC) were used to identify organosulfur and amino acid content of triploid hybrid onion, Allium cornutum Clement ex Visiani, 1842, and common onion, Allium cepa L. Allium extracts were tested for their antiproliferative activity in three human cancer cell lines (HeLa, HCT116, and U2OS). DNA fragmentation and DAPI staining analysis were performed on HeLa cells to evaluate the effect of extracts on DNA damage and cell morphology. The mRNA expression of p53, Bax, and Caspase-3 genes involved in apoptosis were analyzed by real-time PCR. Using GC–MS, 27 compounds were found in two Allium species headspaces. Differences were noted among the main compound abundance in the headspace (although the major thiols and disulfides were qualitatively identic in both Allium species) and dipropyl disulfide, diisopropyl trisulfide, and (Z)-prop-1-enyl propyl trisulfide were predominant sulfides. Identification of amino acids and their quantities were determined by reverse-phase HPLC. Most abundant amino acids in both onions were arginine (Arg) and glutamic acid (Glu). The results of cytotoxicity testing confirmed antiproliferative effects of both species. The DNA fragmentation assay, DAPI staining and real time PCR analysis confirmed that A. cornutum and A. cepa extracts induced apoptosis in HeLa cells. This study presents the evidence for possible therapeutic use of A. cornutum and A. cepa extracts against human cervical carcinoma cell line. Full article

(This article belongs to the Special Issue Medicinal Plants)

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15 pages, 457 KiB

Open AccessEditor’s ChoiceReview

Farming without Glyphosate?

by Hugh J. Beckie, Ken C. Flower and Michael B. Ashworth

Plants 2020, 9(1), 96; https://doi.org/10.3390/plants9010096 - 11 Jan 2020

Cited by 88 | Viewed by 13691

Abstract

Recent statements from scientific organisations and court decisions have resulted in widespread public interest and concern over the safety of glyphosate, the most popular and effective herbicide used worldwide. Consequently, glyphosate-based products are under intense scrutiny from governments at all levels. Some jurisdictions [...] Read more.

Recent statements from scientific organisations and court decisions have resulted in widespread public interest and concern over the safety of glyphosate, the most popular and effective herbicide used worldwide. Consequently, glyphosate-based products are under intense scrutiny from governments at all levels. Some jurisdictions have already banned or restricted its use, which will adversely impact international trade in bulk grain commmodities if glyphosate residues are detected. The possibility of farming without glyphosate is becoming an important issue facing the agri-food research and development sector. Contingency plans need to be formulated if that scenario becomes a reality. In this review, we briefly summarize international events that have led to this possible situation, describe current glyphosate usage in major agronomic field crops worldwide, outline possible alternatives to glyphosate in two agroregions and perform bioeconomic model scenarios of southern Australian broadacre cropping systems without the herbicide. Model predictions suggest that we can farm profitably without glyphosate by consistently utilizing key non-herbicidal weed management practices combined with robust pre-emergence soil residual herbicide treatments. However, maintaining low weed seed banks will be challenging. If the social license to use glyphosate is revoked, what other pesticides will soon follow? Full article

(This article belongs to the Special Issue 2019 Feature Papers by Plants’ Editorial Board Members)

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23 pages, 2054 KiB

Open AccessEditor’s ChoiceReview

Photosynthetic Metabolism under Stressful Growth Conditions as a Bases for Crop Breeding and Yield Improvement

by Fermín Morales, María Ancín, Dorra Fakhet, Jon González-Torralba, Angie L. Gámez, Amaia Seminario, David Soba, Sinda Ben Mariem, Miguel Garriga and Iker Aranjuelo

Plants 2020, 9(1), 88; https://doi.org/10.3390/plants9010088 - 10 Jan 2020

Cited by 112 | Viewed by 15257

Abstract

Increased periods of water shortage and higher temperatures, together with a reduction in nutrient availability, have been proposed as major factors that negatively impact plant development. Photosynthetic CO₂ assimilation is the basis of crop production for animal and human food, and for [...] Read more.

Increased periods of water shortage and higher temperatures, together with a reduction in nutrient availability, have been proposed as major factors that negatively impact plant development. Photosynthetic CO₂ assimilation is the basis of crop production for animal and human food, and for this reason, it has been selected as a primary target for crop phenotyping/breeding studies. Within this context, knowledge of the mechanisms involved in the response and acclimation of photosynthetic CO₂ assimilation to multiple changing environmental conditions (including nutrients, water availability, and rising temperature) is a matter of great concern for the understanding of plant behavior under stress conditions, and for the development of new strategies and tools for enhancing plant growth in the future. The current review aims to analyze, from a multi-perspective approach (ranging across breeding, gas exchange, genomics, etc.) the impact of changing environmental conditions on the performance of the photosynthetic apparatus and, consequently, plant growth. Full article

(This article belongs to the Special Issue Photosynthetic Metabolism under Stressful Growth Conditions)

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63 pages, 5275 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Oxygen and ROS in Photosynthesis

by Sergey Khorobrykh, Vesa Havurinne, Heta Mattila and Esa Tyystjärvi

Plants 2020, 9(1), 91; https://doi.org/10.3390/plants9010091 - 10 Jan 2020

Cited by 163 | Viewed by 14013

Abstract

Oxygen is a natural acceptor of electrons in the respiratory pathway of aerobic organisms and in many other biochemical reactions. Aerobic metabolism is always associated with the formation of reactive oxygen species (ROS). ROS may damage biomolecules but are also involved in regulatory [...] Read more.

Oxygen is a natural acceptor of electrons in the respiratory pathway of aerobic organisms and in many other biochemical reactions. Aerobic metabolism is always associated with the formation of reactive oxygen species (ROS). ROS may damage biomolecules but are also involved in regulatory functions of photosynthetic organisms. This review presents the main properties of ROS, the formation of ROS in the photosynthetic electron transport chain and in the stroma of chloroplasts, and ROS scavenging systems of thylakoid membrane and stroma. Effects of ROS on the photosynthetic apparatus and their roles in redox signaling are discussed. Full article

(This article belongs to the Special Issue ROS Responses in Plants)

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15 pages, 1040 KiB

Open AccessEditor’s ChoiceArticle

Effects of Arbuscular Mycorrhizal Fungi on Yield, Biochemical Characteristics, and Elemental Composition of Garlic and Onion under Selenium Supply

by Nadezhda Golubkina, Zarema Amagova, Visita Matsadze, Svetlana Zamana, Alessio Tallarita and Gianluca Caruso

Plants 2020, 9(1), 84; https://doi.org/10.3390/plants9010084 - 9 Jan 2020

Cited by 42 | Viewed by 4377

Abstract

Biofortification of garlic and onion plants with selenium and arbuscular mycorrhizal fungi inoculation are considered beneficial for producing functional food with anticarcinogenic properties. The effects of arbuscular mycorrhizal fungi (AMF) inoculation, sodium selenate foliar application, and the combination AMF + selenium (Se), compared [...] Read more.

Biofortification of garlic and onion plants with selenium and arbuscular mycorrhizal fungi inoculation are considered beneficial for producing functional food with anticarcinogenic properties. The effects of arbuscular mycorrhizal fungi (AMF) inoculation, sodium selenate foliar application, and the combination AMF + selenium (Se), compared to an untreated control, were assessed regarding the bulb yield, biochemical characteristics, and mineral composition. AMF + Se application resulted in the highest yield, monosaccharides, and Se content in both garlic and onion bulbs; and an increase of ascorbic acid and flavonoids in onion, and flavonoids in garlic. The highest bulb concentrations of P and K were recorded under the AMF + Se application, Ca was best affected by AMF, and Mg accumulation was highest under all the treatments in garlic and upon AMF + Se application in onion bulbs. Contrary to garlic, onion bulbs were characterized by a remarkable increase in microelements (B, Cu, Fe, Mn, Si, Zn) under the AMF + Se treatment. Selenium, either with or without AMF application, promoted the accumulation of B and Si in onion and Mo and Zn in garlic bulbs. It can be inferred that the interaction between AMF and Se is highly specific, differing for garlic and onion grown in similar environmental conditions in Grozny region, Chechen Republic. Full article

(This article belongs to the Special Issue Factors Affecting Yield, Quality, Antioxidants, Mineral Composition and Residual Biomass Valorization of Vegetable Crops)

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19 pages, 1646 KiB

Open AccessEditor’s ChoiceArticle

Arbuscular Mycorrhizal Fungi Mediate Drought Tolerance and Recovery in Two Contrasting Carob (Ceratonia siliqua L.) Ecotypes by Regulating Stomatal, Water Relations, and (In)Organic Adjustments

by Abderrahim Boutasknit, Marouane Baslam, Mohamed Ait-El-Mokhtar, Mohamed Anli, Raja Ben-Laouane, Allal Douira, Cherkaoui El Modafar, Toshiaki Mitsui, Said Wahbi and Abdelilah Meddich

Plants 2020, 9(1), 80; https://doi.org/10.3390/plants9010080 - 8 Jan 2020

Cited by 93 | Viewed by 7201

Abstract

Irregular precipitation and drought caused an increase in tree mortality rates in multiple forest biomes with alterations in both ecosystem services and carbon balance. Carob (Ceratonia siliqua) growth and production in arid and semi-arid ecosystems are likely affected by climate change-induced [...] Read more.

Irregular precipitation and drought caused an increase in tree mortality rates in multiple forest biomes with alterations in both ecosystem services and carbon balance. Carob (Ceratonia siliqua) growth and production in arid and semi-arid ecosystems are likely affected by climate change-induced droughts. Understanding the physiological responses of drought-induced early-stage tree death and strategies to enhance drought tolerance and optimize growth will help tree improvement programs. Mycorrhizal inoculation has a pronounced impact on plant growth, water absorption, mineral nutrition, and protection from abiotic stresses. However, a better understanding of these complex interconnected cellular processes and arbuscular mycorrhizal fungi (AMF)-mediated mechanisms regulating drought tolerance in plants will enhance its potential application as an efficient approach for bio-amelioration of stresses. The objectives of this work were to elucidate the different effects of autochthone AMF on inorganic solute and water content uptakes, organic adjustments (sugar and proteins content), leaf gas exchange (stomatal conductance and efficiency of photosystems I and II), and oxidative damage of two contrasting ecotypes of carob seedlings: coastal (southern ecotype (SE)) and in-land (northern ecotype (NE)) under control (C), drought (by cessation of irrigation for 15 days (15D)), and recovery (R) conditions. Our findings showed that AMF promoted growth, nutrient content, and physiological and biochemical parameters in plants of both ecotypes during C, 15D, and R conditions. After four days of recovery, stomatal conductance (g_s), the maximum photochemical efficiency of PSII (F_v/F_m), water content, and plant uptake of mineral nutrients (P, K, Na, and Ca) were significantly higher in shoots of mycorrhizal (AM) than non-mycorrhizal (NM) control plants. Consequently, AMF reduced to a greater degree the accumulation of hydrogen peroxide (H₂O₂) and oxidative damage to lipid (malondialdehyde (MDA)) content in AM than NM plants in NE and SE, after recovery. Altogether, our findings suggest that AMF can play a role in drought resistance of carob trees at an early stage by increasing the inorganic solutes (P, K, Na, and Ca), water content uptake, organic solutes (soluble sugars and protein content), stomatal conductance, and defense response against oxidative damage during re-watering after drought stress. Full article

(This article belongs to the Special Issue Photosynthetic Metabolism under Stressful Growth Conditions)

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22 pages, 4346 KiB

Open AccessEditor’s ChoiceArticle

Effects of Endophytic Bacillus Subtilis and Salicylic Acid on Postharvest Diseases (Phytophthora infestans, Fusarium oxysporum) Development in Stored Potato Tubers

by Oksana Lastochkina, Andrey Baymiev, Aysylu Shayahmetova, Darya Garshina, Igor Koryakov, Irina Shpirnaya, Liudmila Pusenkova, Il’dar Mardanshin, Cemal Kasnak and Recep Palamutoglu

Plants 2020, 9(1), 76; https://doi.org/10.3390/plants9010076 - 7 Jan 2020

Cited by 55 | Viewed by 6517

Abstract

Postharvest diseases of potato lead to significant food and economic losses worldwide. The exogenous application of eco-friendly methods plays an important role in the control of postharvest decay. In this work the effects of endophytic bacteria B. subtilis (10-4, 26D) were studied in [...] Read more.

Postharvest diseases of potato lead to significant food and economic losses worldwide. The exogenous application of eco-friendly methods plays an important role in the control of postharvest decay. In this work the effects of endophytic bacteria B. subtilis (10-4, 26D) were studied in the context of two application parameters: concentration, with a range between 10³–10⁸ CFU/mL tested, and synergistic effects of the signal molecule salicylic acid (SA) (0.05 mM) on potato tubers’ resistance to Phytophthora infestans and Fusarium oxysporum during storage. The experiments were carried out on hydroponically grown potato (Solanum tuberosum L.) mini-tubers. This study demonstrates the suppressive effect of B. subtilis (10-4, 26D) on diseases of potato during storage and reveals that this effect happens in a dose-dependent manner, both individually and in combination with SA. The most effective concentrations of B. subtilis for suppression of both Ph. infestans and F. oxysporum are 10⁸ CFU/mL (10-4 and 26D), 10⁷ CFU/mL (10-4 + SA) and 10⁶ CFU/mL (26D + SA). The ability of B. subtilis (10-4, 26D) to effectively penetrate and colonize the internal tubers’ tissues when applied immediately prior to storage, and the ability of SA to accelerate these processes, have been proven. B. subtilis (10-4, 26D), individually and in compositions with SA, increased ascorbic acid content and decreased pathogen-induced proline accumulation and lipid peroxidation in tubers. This indicates a protective effect conferred to cells against reactive oxygen and an extension of aging processes, manifested by a prolonged shelf life and extended preservation of fresh appearance. Full article

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29 pages, 556 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Biofortification of Pulse Crops: Status and Future Perspectives

by Ambuj B. Jha and Thomas D. Warkentin

Plants 2020, 9(1), 73; https://doi.org/10.3390/plants9010073 - 6 Jan 2020

Cited by 131 | Viewed by 15835

Abstract

Biofortification through plant breeding is a sustainable approach to improve the nutritional profile of food crops. The majority of the world’s population depends on staple food crops; however, most are low in key micronutrients. Biofortification to improve the nutritional profile of pulse crops [...] Read more.

Biofortification through plant breeding is a sustainable approach to improve the nutritional profile of food crops. The majority of the world’s population depends on staple food crops; however, most are low in key micronutrients. Biofortification to improve the nutritional profile of pulse crops has increased importance in many breeding programs in the past decade. The key micronutrients targeted have been iron, zinc, selenium, iodine, carotenoids, and folates. In recent years, several biofortified pulse crops including common beans and lentils have been released by HarvestPlus with global partners in developing countries, which has helped in overcoming micronutrient deficiency in the target population. This review will focus on recent research advances and future strategies for the biofortification of pulse crops. Full article

(This article belongs to the Special Issue Phytic Acid and Mineral Biofortification Strategies: From Plant Science to Breeding and Biotechnological Approaches)

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20 pages, 2345 KiB

Open AccessEditor’s ChoiceReview

Phytic Acid and Transporters: What Can We Learn from low phytic acid Mutants?

by Eleonora Cominelli, Roberto Pilu and Francesca Sparvoli

Plants 2020, 9(1), 69; https://doi.org/10.3390/plants9010069 - 5 Jan 2020

Cited by 38 | Viewed by 6045

Abstract

Phytic acid has two main roles in plant tissues: Storage of phosphorus and regulation of different cellular processes. From a nutritional point of view, it is considered an antinutritional compound because, being a cation chelator, its presence reduces mineral bioavailability from the diet. [...] Read more.

Phytic acid has two main roles in plant tissues: Storage of phosphorus and regulation of different cellular processes. From a nutritional point of view, it is considered an antinutritional compound because, being a cation chelator, its presence reduces mineral bioavailability from the diet. In recent decades, the development of low phytic acid (lpa) mutants has been an important goal for nutritional seed quality improvement, mainly in cereals and legumes. Different lpa mutations affect phytic acid biosynthetic genes. However, other lpa mutations isolated so far, affect genes coding for three classes of transporters: A specific group of ABCC type vacuolar transporters, putative sulfate transporters, and phosphate transporters. In the present review, we summarize advances in the characterization of these transporters in cereals and legumes. Particularly, we describe genes, proteins, and mutants for these different transporters, and we report data of in silico analysis aimed at identifying the putative orthologs in some other cereal and legume species. Finally, we comment on the advantage of using such types of mutants for crop biofortification and on their possible utility to unravel links between phosphorus and sulfur metabolism (phosphate and sulfate homeostasis crosstalk). Full article

(This article belongs to the Special Issue Phytic Acid and Mineral Biofortification Strategies: From Plant Science to Breeding and Biotechnological Approaches)

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25 pages, 1999 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Potential and Challenges of Improving Photosynthesis in Algae

by Valeria Vecchi, Simone Barera, Roberto Bassi and Luca Dall’Osto

Plants 2020, 9(1), 67; https://doi.org/10.3390/plants9010067 - 3 Jan 2020

Cited by 94 | Viewed by 16704

Abstract

Sunlight energy largely exceeds the energy required by anthropic activities, and therefore its exploitation represents a major target in the field of renewable energies. The interest in the mass cultivation of green microalgae has grown in the last decades, as algal biomass could [...] Read more.

Sunlight energy largely exceeds the energy required by anthropic activities, and therefore its exploitation represents a major target in the field of renewable energies. The interest in the mass cultivation of green microalgae has grown in the last decades, as algal biomass could be employed to cover a significant portion of global energy demand. Advantages of microalgal vs. plant biomass production include higher light-use efficiency, efficient carbon capture and the valorization of marginal lands and wastewaters. Realization of this potential requires a decrease of the current production costs, which can be obtained by increasing the productivity of the most common industrial strains, by the identification of factors limiting biomass yield, and by removing bottlenecks, namely through domestication strategies aimed to fill the gap between the theoretical and real productivity of algal cultures. In particular, the light-to-biomass conversion efficiency represents one of the major constraints for achieving a significant improvement of algal cell lines. This review outlines the molecular events of photosynthesis, which regulate the conversion of light into biomass, and discusses how these can be targeted to enhance productivity through mutagenesis, strain selection or genetic engineering. This review highlights the most recent results in the manipulation of the fundamental mechanisms of algal photosynthesis, which revealed that a significant yield enhancement is feasible. Moreover, metabolic engineering of microalgae, focused upon the development of renewable fuel biorefineries, has also drawn attention and resulted in efforts for enhancing productivity of oil or isoprenoids. Full article

(This article belongs to the Section Plant Physiology and Metabolism)

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9 pages, 1082 KiB

Open AccessEditor’s ChoiceArticle

PAST: The Pathway Association Studies Tool to Infer Biological Meaning from GWAS Datasets

by Adam Thrash, Juliet D. Tang, Mason DeOrnellis, Daniel G. Peterson and Marilyn L. Warburton

Plants 2020, 9(1), 58; https://doi.org/10.3390/plants9010058 - 2 Jan 2020

Cited by 19 | Viewed by 6695

Abstract

In recent years, a bioinformatics method for interpreting genome-wide association study (GWAS) data using metabolic pathway analysis has been developed and successfully used to find significant pathways and mechanisms explaining phenotypic traits of interest in plants. However, the many scripts implementing this method [...] Read more.

In recent years, a bioinformatics method for interpreting genome-wide association study (GWAS) data using metabolic pathway analysis has been developed and successfully used to find significant pathways and mechanisms explaining phenotypic traits of interest in plants. However, the many scripts implementing this method were not straightforward to use, had to be customized for each project, required user supervision, and took more than 24 h to process data. PAST (Pathway Association Study Tool), a new implementation of this method, has been developed to address these concerns. PAST has been implemented as a package for the R language. Two user-interfaces are provided; PAST can be run by loading the package in R and calling its methods, or by using an R Shiny guided user interface. In testing, PAST completed analyses in approximately half an hour to one hour by processing data in parallel and produced the same results as the previously developed method. PAST has many user-specified options for maximum customization. Thus, to promote a powerful new pathway analysis methodology that interprets GWAS data to find biological mechanisms associated with traits of interest, we developed a more accessible, efficient, and user-friendly tool. These attributes make PAST accessible to researchers interested in associating metabolic pathways with GWAS datasets to better understand the genetic architecture and mechanisms affecting phenotypes. Full article

(This article belongs to the Special Issue Plant Bioinformatics)

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15 pages, 1079 KiB

Open AccessEditor’s ChoiceArticle

Sustainability Perspectives of Vigna unguiculata L. Walp. Cultivation under No Tillage and Water Stress Conditions

by Lorenzo Guzzetti, Andrea Fiorini, Davide Panzeri, Nicola Tommasi, Fabrizio Grassi, Eren Taskin, Chiara Misci, Edoardo Puglisi, Vincenzo Tabaglio, Andrea Galimberti and Massimo Labra

Plants 2020, 9(1), 48; https://doi.org/10.3390/plants9010048 - 30 Dec 2019

Cited by 23 | Viewed by 4527

Abstract

Nowadays, agriculture is facing the great challenge of climate change which puts the productivity of the crops in peril due to unpredictable rain patterns and water shortages, especially in the developing world. Besides productivity, nutritional values of the yields of these crops may [...] Read more.

Nowadays, agriculture is facing the great challenge of climate change which puts the productivity of the crops in peril due to unpredictable rain patterns and water shortages, especially in the developing world. Besides productivity, nutritional values of the yields of these crops may also be affected, especially under low mechanization and the low water availability conditions of the developing world. Conservation agriculture (CA) is a topic of emerging interest due to the provision of adequate yields and reduced environmental impact, such as greenhouse gas emissions, by being based on three main principles: minimum soil disturbance (reduced or no tillage), cover crop maintenance, and crop rotation. The aim of this study was to assess the impact of CA management on the growth performance and the nutritional profile of cowpea (Vigna unguiculata L. Walp), a pulse of African origin, commonly known as black eye bean under field conditions. A field experiment was designed to assess the effect of conventional tillage (CT) and no-tillage (NT) combined with the usage of a set of cover crops, coupled to normal and deficient water regimes. Cowpea was revealed to be able to grow and yield comparably at each level of the treatment tested, with a better ability to face water exhaustion under CA management. After a faster initial growth phase in CT plots, the level of adaptability of this legume to NT was such that growth performances improved significantly with respect to CT plots. The flowering rate was higher and earlier in CT conditions, while in NT it was slower but longer-lasting. The leafy photosynthetic rate and the nutritional profile of beans were slightly influenced by tillage management: only total starch content was negatively affected in NT and watered plots while proteins and aminoacids did not show any significant variation. Furthermore, significantly higher carbon and nitrogen concentration occurred in NT soils especially at the topmost (0–5 cm) soil horizon. These findings confirm the capability of CA to enrich soil superficial horizons and highlight that cowpea is a suitable crop to be grown under sustainable CA management. This practice could be pivotal to preserve soils and to save agronomical costs without losing a panel of nutrients that are important to the human diet. Due to its great protein and aminoacidic composition, V. unguiculata is a good candidate for further cultivation in regions of the word facing deficiencies in the intake of such nutrients, such as the Mediterranean basins and Sub-Saharan countries. Full article

(This article belongs to the Special Issue Selected Plant-Related Papers from the First Joint Meeting on Soil and Plant System Sciences (SPSS 2019) “Natural and Human-induced Impacts on the Critical Zone and Food Production”)

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21 pages, 755 KiB

Open AccessEditor’s ChoiceReview

Development of Systems for the Production of Plant-Derived Biopharmaceuticals

by Ki-Beom Moon, Ji-Sun Park, Youn-Il Park, In-Ja Song, Hyo-Jun Lee, Hye Sun Cho, Jae-Heung Jeon and Hyun-Soon Kim

Plants 2020, 9(1), 30; https://doi.org/10.3390/plants9010030 - 24 Dec 2019

Cited by 75 | Viewed by 16289

Abstract

Over the last several decades, plants have been developed as a platform for the production of useful recombinant proteins due to a number of advantages, including rapid production and scalability, the ability to produce unique glycoforms, and the intrinsic safety of food crops. [...] Read more.

Over the last several decades, plants have been developed as a platform for the production of useful recombinant proteins due to a number of advantages, including rapid production and scalability, the ability to produce unique glycoforms, and the intrinsic safety of food crops. The expression methods used to produce target proteins are divided into stable and transient systems depending on applications that use whole plants or minimally processed forms. In the early stages of research, stable expression systems were mostly used; however, in recent years, transient expression systems have been preferred. The production of the plant itself, which produces recombinant proteins, is currently divided into two major approaches, open-field cultivation and closed-indoor systems. The latter encompasses such regimes as greenhouses, vertical farming units, cell bioreactors, and hydroponic systems. Various aspects of each system will be discussed in this review, which focuses mainly on practical examples and commercially feasible approaches. Full article

(This article belongs to the Special Issue Plant Expression Systems for Bioproduct Production)

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17 pages, 681 KiB

Open AccessEditor’s ChoiceArticle

Effect of Light Intensity and Quality on Growth Rate and Composition of Chlorella vulgaris

by Maria N. Metsoviti, George Papapolymerou, Ioannis T. Karapanagiotidis and Nikolaos Katsoulas

Plants 2020, 9(1), 31; https://doi.org/10.3390/plants9010031 - 24 Dec 2019

Cited by 147 | Viewed by 13369

Abstract

In this research, the effect of solar irradiance on Chlorella vulgaris cultivated in open bioreactors under greenhouse conditions was investigated, as well as of ratio of light intensity in the 420–520 nm range to light in the 580–680 nm range (I_420–520/I [...] Read more.

In this research, the effect of solar irradiance on Chlorella vulgaris cultivated in open bioreactors under greenhouse conditions was investigated, as well as of ratio of light intensity in the 420–520 nm range to light in the 580–680 nm range (I_420–520/I_580–680) and of artificial irradiation provided by red and white LED lamps in a closed flat plate laboratory bioreactor on the growth rate and composition. The increase in solar irradiance led to faster growth rates (μ_exp) of C. vulgaris under both environmental conditions studied in the greenhouse (in June up to 0.33 d⁻¹ and in September up to 0.29 d⁻¹) and higher lipid content in microalgal biomass (in June up to 25.6% and in September up to 24.7%). In the experiments conducted in the closed bioreactor, as the ratio I_420–520/I_580–680 increased, the specific growth rate and the biomass, protein and lipid productivities increased as well. Additionally, the increase in light intensity with red and white LED lamps resulted in faster growth rates (the μ_exp increased up to 0.36 d⁻¹) and higher lipid content (up to 22.2%), while the protein, fiber, ash and moisture content remained relatively constant. Overall, the trend in biomass, lipid, and protein productivities as a function of light intensity was similar in the two systems (greenhouse and bioreactor). Full article

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16 pages, 2709 KiB

Open AccessEditor’s ChoiceArticle

Insight into Composition of Bioactive Phenolic Compounds in Leaves and Flowers of Green and Purple Basil

by Bhakti Prinsi, Silvia Morgutti, Noemi Negrini, Franco Faoro and Luca Espen

Plants 2020, 9(1), 22; https://doi.org/10.3390/plants9010022 - 23 Dec 2019

Cited by 70 | Viewed by 8560

Abstract

Basil (Ocimum basilicum L.) is a culinary, medicinal, and ornamental plant appreciated for its antioxidant properties, mainly attributed to high content of rosmarinic acid. This species also includes purple varieties, characterized by the accumulation of anthocyanins in leaves and flowers. In this [...] Read more.

Basil (Ocimum basilicum L.) is a culinary, medicinal, and ornamental plant appreciated for its antioxidant properties, mainly attributed to high content of rosmarinic acid. This species also includes purple varieties, characterized by the accumulation of anthocyanins in leaves and flowers. In this work, we compared the main morphological characteristics, the antioxidant capacity and the chemical composition in leaves, flowers, and corollas of green (‘Italiano Classico’) and purple (‘Red Rubin’ and ‘Dark Opal’) basil varieties. The LC-ESI-MS/MS analysis of individual compounds allowed quantifying 17 (poly)phenolic acids and 18 flavonoids, differently accumulated in leaves and flowers of the three varieties. The study revealed that in addition to rosmarinic acid, basil contains several members of the salvianolic acid family, only scarcely descripted in this species, as well as, especially in flowers, simple phenolic acids, such as 4-hydroxybenzoic acid and salvianic acid A. Moreover, the study revealed that purple leaves mainly contain highly acylated anthocyanins, while purple flowers accumulate anthocyanins with low degree of decoration. Overall, this study provides new biochemical information about the presence of not yet characterized bioactive compounds in basil that could contribute to boosting the use of this crop and to gaining new knowledge about the roles of these compounds in plant physiology. Full article

(This article belongs to the Special Issue Plant Polyphenols—from Plants to Human Health)

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17 pages, 9230 KiB

Open AccessEditor’s ChoiceReview

Alpha Glucosidase Inhibitory Activities of Plants with Focus on Common Vegetables

by Samuel Tilahun Assefa, Eun-Young Yang, Soo-Young Chae, Mihye Song, Jundae Lee, Myeong-Cheoul Cho and Seonghoe Jang

Plants 2020, 9(1), 2; https://doi.org/10.3390/plants9010002 - 18 Dec 2019

Cited by 111 | Viewed by 16535

Abstract

Type-2 diabetes mellitus is one of the most prevalent metabolic diseases in the world, and is characterized by hyperglycemia (i.e., high levels of glucose in the blood). Alpha-glucosidases are enzymes in the digestive tract that hydrolyze carbohydrates into glucose. One strategy that has [...] Read more.

Type-2 diabetes mellitus is one of the most prevalent metabolic diseases in the world, and is characterized by hyperglycemia (i.e., high levels of glucose in the blood). Alpha-glucosidases are enzymes in the digestive tract that hydrolyze carbohydrates into glucose. One strategy that has been developed to treat type-2 diabetes is inhibition of the activity of alpha-glucosidases using synthetic drugs. However, these inhibitors are usually associated with gastrointestinal side effects. Therefore, the development of inhibitors from natural products offers an alternative option for the control of hyperglycemia. In recent years, various studies have been conducted to identify alpha-glucosidases inhibitors from natural sources such as plants, and many candidates have transpired to be secondary metabolites including alkaloids, flavonoids, phenols, and terpenoids. In this review, we focus on the alpha-glucosidases inhibitors found in common vegetable crops and the major classes of phytochemicals responsible for the inhibitory activity, and also as potential/natural drug candidates for the treatment of type-2 diabetes mellitus. In addition, possible breeding strategies for production of improved vegetable crops with higher content of the inhibitors are also described. Full article

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23 pages, 797 KiB

Open AccessEditor’s ChoiceReview

The Role of Plant-Associated Microbes in Mediating Host-Plant Selection by Insect Herbivores

by John M. Grunseich, Morgan N. Thompson, Natalie M. Aguirre and Anjel M. Helms

Plants 2020, 9(1), 6; https://doi.org/10.3390/plants9010006 - 18 Dec 2019

Cited by 40 | Viewed by 12945

Abstract

There is increasing evidence that plant-associated microorganisms play important roles in shaping interactions between plants and insect herbivores. Studies of both pathogenic and beneficial plant microbes have documented wide-ranging effects on herbivore behavior and performance. Some studies, for example, have reported enhanced insect-repellent [...] Read more.

There is increasing evidence that plant-associated microorganisms play important roles in shaping interactions between plants and insect herbivores. Studies of both pathogenic and beneficial plant microbes have documented wide-ranging effects on herbivore behavior and performance. Some studies, for example, have reported enhanced insect-repellent traits or reduced performance of herbivores on microbe-associated plants, while others have documented increased herbivore attraction or performance. Insect herbivores frequently rely on plant cues during foraging and oviposition, suggesting that plant-associated microbes affecting these cues can indirectly influence herbivore preference. We review and synthesize recent literature to provide new insights into the ways pathogenic and beneficial plant-associated microbes alter visual, olfactory, and gustatory cues of plants that affect host-plant selection by insect herbivores. We discuss the underlying mechanisms, ecological implications, and future directions for studies of plant-microbial symbionts that indirectly influence herbivore behavior by altering plant traits. Full article

(This article belongs to the Special Issue Insect-Plant-Microbe Interactions)

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11 pages, 267 KiB

Open AccessEditor’s ChoiceArticle

United Forces of Botanical Oils: Efficacy of Neem and Karanja Oil against Colorado Potato Beetle under Laboratory Conditions

by Kateřina Kovaříková and Roman Pavela

Plants 2019, 8(12), 608; https://doi.org/10.3390/plants8120608 - 14 Dec 2019

Cited by 15 | Viewed by 4750

Abstract

Neem and karanja oil are the most promising botanical insecticides in crop protection nowadays. Given that information about the insecticidal abilities of these oils is lacking, the aim was to explore the effects of neem and karanja oil binary mixtures. The insecticidal activity [...] Read more.

Neem and karanja oil are the most promising botanical insecticides in crop protection nowadays. Given that information about the insecticidal abilities of these oils is lacking, the aim was to explore the effects of neem and karanja oil binary mixtures. The insecticidal activity of NeemAzal T/S (Trifolio-M GmbH, Lahnau, Germany) (neem oil), Rock Effect (Agro CS a.s., Česká Skalice, Czech Republic) (karanja oil), and their binary mixes (at 1:1, 1:2, and 2:1 volume ratios) against the larvae of the Colorado potato beetle (CPB; Leptinotarsa decemlineata) was studied. In our bioassays, a synergistic effect of the mixtures, which was dose-dependent, was observed for the first time against this pest. The most effective blend was the 1:1 ratio. Its efficacy was more or less the same as, or even greater than, the neem oil alone. The LC₅₀ of neem oil two days after application was (0.075 g·L⁻¹) and the LC₅₀ of the mixture was (0.065 g·L⁻¹). The LC₅₀ of karanja oil was (0.582 g·L⁻¹), which was much higher than the LC₅₀ of neem oil. The LC₉₀ of neem oil five days after application was (0.105 g·L⁻¹) and the LC₉₀ of the mixture was (0.037 g·L⁻¹). The LC₉₀ of karanja oil was (1.032 g·L⁻¹). The results demonstrate that it is possible to lower the doses of both oils and get improved efficacy against CPB larvae; nevertheless, further verification of the results in field conditions is necessary. Full article

(This article belongs to the Special Issue Pesticidal Plants: From Smallholder Use to Commercialisation)

22 pages, 1273 KiB

Open AccessEditor’s ChoiceReview

Development of Improved Fruit, Vegetable, and Ornamental Crops Using the CRISPR/Cas9 Genome Editing Technique

by Lígia Erpen-Dalla Corte, Lamiaa M. Mahmoud, Tatiana S. Moraes, Zhonglin Mou, Jude W. Grosser and Manjul Dutt

Plants 2019, 8(12), 601; https://doi.org/10.3390/plants8120601 - 13 Dec 2019

Cited by 64 | Viewed by 11008

Abstract

Horticultural crops, including fruit, vegetable, and ornamental plants are an important component of the agriculture production systems and play an important role in sustaining human life. With a steady growth in the world’s population and the consequent need for more food, sustainable and [...] Read more.

Horticultural crops, including fruit, vegetable, and ornamental plants are an important component of the agriculture production systems and play an important role in sustaining human life. With a steady growth in the world’s population and the consequent need for more food, sustainable and increased fruit and vegetable crop production is a major challenge to guarantee future food security. Although conventional breeding techniques have significantly contributed to the development of important varieties, new approaches are required to further improve horticultural crop production. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has emerged as a valuable genome-editing tool able to change DNA sequences at precisely chosen loci. The CRISPR/Cas9 system was developed based on the bacterial adaptive immune system and comprises of an endonuclease guided by one or more single-guide RNAs to generate double-strand breaks. These breaks can then be repaired by the natural cellular repair mechanisms, during which genetic mutations are introduced. In a short time, the CRISPR/Cas9 system has become a popular genome-editing technique, with numerous examples of gene mutation and transcriptional regulation control in both model and crop plants. In this review, various aspects of the CRISPR/Cas9 system are explored, including a general presentation of the function of the CRISPR/Cas9 system in bacteria and its practical application as a biotechnological tool for editing plant genomes, particularly in horticultural crops. Full article

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14 pages, 304 KiB

Open AccessEditor’s ChoiceArticle

Comparative Evaluation of the Nutritive, Mineral, and Antinutritive Composition of Musa sinensis L. (Banana) and Musa paradisiaca L. (Plantain) Fruit Compartments

by Barnabas Oluwatomide Oyeyinka and Anthony Jide Afolayan

Plants 2019, 8(12), 598; https://doi.org/10.3390/plants8120598 - 12 Dec 2019

Cited by 61 | Viewed by 10883

Abstract

Banana and plantain contribute significantly to food security and amelioration of malnutrition, earning their status as staples in several localities of tropical and sub-tropical regions. The distribution of metabolites within the various parts also remains as a key essential to their nutritive and [...] Read more.

Banana and plantain contribute significantly to food security and amelioration of malnutrition, earning their status as staples in several localities of tropical and sub-tropical regions. The distribution of metabolites within the various parts also remains as a key essential to their nutritive and therapeutic potential. This study was aimed at evaluating the nutritional and mineral composition of the flesh, peel, and peel extract components of Musa sinensis L. and Musa paradisiaca L. fruits as well as their nutritional and therapeutic potentials. Proximate and antinutritional analyses were carried out using standard analytical methods of the Association of Official Analytical Chemists (AOAC), while the mineral constituents were evaluated using inductively coupled plasma optical emission spectroscopy (ICP-OES). Proximate analysis revealed that the flesh and peel of M. sinensis L. and M. paradisiaca L. contain substantial amounts of moisture, fiber, carbohydrates, and low fat content, while minerals K, Mg, Ca, Na, P, and N were substantially concentrated in the peels and peel extracts in particular. The antinutrients alkaloid, oxalate, saponin, and phytate were detected in safe amounts according to the World Health Organization (WHO). The study points out that the peel and its derivative extract, as well as the flesh of M. sinensis L. and M. paradisiaca L. are to be put to more relevant human nutritional and therapeutic use. Full article

(This article belongs to the Section Phytochemistry)

20 pages, 1613 KiB

Open AccessEditor’s ChoiceReview

Integration of Abscisic Acid Signaling with Other Signaling Pathways in Plant Stress Responses and Development

by Manu Kumar, Mahipal Singh Kesawat, Asjad Ali, Sang-Choon Lee, Sarvajeet Singh Gill and Hyun Uk Kim

Plants 2019, 8(12), 592; https://doi.org/10.3390/plants8120592 - 11 Dec 2019

Cited by 94 | Viewed by 11151

Abstract

Plants are immobile and, to overcome harsh environmental conditions such as drought, salt, and cold, they have evolved complex signaling pathways. Abscisic acid (ABA), an isoprenoid phytohormone, is a critical signaling mediator that regulates diverse biological processes in various organisms. Significant progress has [...] Read more.

Plants are immobile and, to overcome harsh environmental conditions such as drought, salt, and cold, they have evolved complex signaling pathways. Abscisic acid (ABA), an isoprenoid phytohormone, is a critical signaling mediator that regulates diverse biological processes in various organisms. Significant progress has been made in the determination and characterization of key ABA-mediated molecular factors involved in different stress responses, including stomatal closure and developmental processes, such as seed germination and bud dormancy. Since ABA signaling is a complex signaling network that integrates with other signaling pathways, the dissection of its intricate regulatory network is necessary to understand the function of essential regulatory genes involved in ABA signaling. In the present review, we focus on two aspects of ABA signaling. First, we examine the perception of the stress signal (abiotic and biotic) and the response network of ABA signaling components that transduce the signal to the downstream pathway to respond to stress tolerance, regulation of stomata, and ABA signaling component ubiquitination. Second, ABA signaling in plant development processes, such as lateral root growth regulation, seed germination, and flowering time regulation is investigated. Examining such diverse signal integration dynamics could enhance our understanding of the underlying genetic, biochemical, and molecular mechanisms of ABA signaling networks in plants. Full article

(This article belongs to the Special Issue 2019 Feature Papers by Plants’ Editorial Board Members)

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14 pages, 1255 KiB

Open AccessEditor’s ChoiceReview

Arabidopsis WRKY53, a Node of Multi-Layer Regulation in the Network of Senescence

by Ulrike Zentgraf and Jasmin Doll

Plants 2019, 8(12), 578; https://doi.org/10.3390/plants8120578 - 6 Dec 2019

Cited by 49 | Viewed by 5345

Abstract

Leaf senescence is an integral part of plant development aiming at the remobilization of nutrients and minerals out of the senescing tissue into developing parts of the plant. Sequential as well as monocarpic senescence maximize the usage of nitrogen, mineral, and carbon resources [...] Read more.

Leaf senescence is an integral part of plant development aiming at the remobilization of nutrients and minerals out of the senescing tissue into developing parts of the plant. Sequential as well as monocarpic senescence maximize the usage of nitrogen, mineral, and carbon resources for plant growth and the sake of the next generation. However, stress-induced premature senescence functions as an exit strategy to guarantee offspring under long-lasting unfavorable conditions. In order to coordinate this complex developmental program with all kinds of environmental input signals, complex regulatory cues have to be in place. Major changes in the transcriptome imply important roles for transcription factors. Among all transcription factor families in plants, the NAC and WRKY factors appear to play central roles in senescence regulation. In this review, we summarize the current knowledge on the role of WRKY factors with a special focus on WRKY53. In contrast to a holistic multi-omics view we want to exemplify the complexity of the network structure by summarizing the multilayer regulation of WRKY53 of Arabidopsis. Full article

(This article belongs to the Special Issue Leaf Senescence)

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18 pages, 2094 KiB

Open AccessEditor’s ChoiceReview

Bacterium-Mediated RNA Interference: Potential Application in Plant Protection

by Simon Goodfellow, Daai Zhang, Ming-Bo Wang and Ren Zhang

Plants 2019, 8(12), 572; https://doi.org/10.3390/plants8120572 - 5 Dec 2019

Cited by 17 | Viewed by 7910

Abstract

RNAi has emerged as a promising tool for targeting agricultural pests and pathogens and could provide an environmentally friendly alternative to traditional means of control. However, the deployment of this technology is still limited by a lack of suitable exogenous- or externally applied [...] Read more.

RNAi has emerged as a promising tool for targeting agricultural pests and pathogens and could provide an environmentally friendly alternative to traditional means of control. However, the deployment of this technology is still limited by a lack of suitable exogenous- or externally applied delivery mechanisms. Numerous means of overcoming this limitation are being explored. One such method, bacterium-mediated RNA interference, or bmRNAi, has been explored in other systems and shows great potential for application to agriculture. Here, we review the current state of bmRNAi, examine the technical limitations and possible improvements, and discuss its potential applications in crop protection. Full article

(This article belongs to the Special Issue RNAs and Plant Disease Resistance)

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19 pages, 2523 KiB

Open AccessEditor’s ChoiceArticle

Optimize, Modulate, and Scale-up Resveratrol and Resveratrol Dimers Bioproduction in Vitis labrusca L. Cell Suspension from Flasks to 20 L Bioreactor

by Carole Lambert, Julien Lemaire, Hélène Auger, Arnaud Guilleret, Romain Reynaud, Christophe Clément, Eric Courot and Behnam Taidi

Plants 2019, 8(12), 567; https://doi.org/10.3390/plants8120567 - 4 Dec 2019

Cited by 25 | Viewed by 4476

Abstract

Resveratrol and its oligomers are biologically active compounds. This work brings new insights for the bioproduction of trans-resveratrol with three dimers, pallidol, trans-ε-viniferin, and trans-δ-viniferin, in cell suspension of Vitis labrusca. Conditions of elicitation by methyl jasmonate were optimized [...] Read more.

Resveratrol and its oligomers are biologically active compounds. This work brings new insights for the bioproduction of trans-resveratrol with three dimers, pallidol, trans-ε-viniferin, and trans-δ-viniferin, in cell suspension of Vitis labrusca. Conditions of elicitation by methyl jasmonate were optimized for the production of stilbenes using statistical design of experiment. Bio-production of stilbenes was scaled-up to 5 L and in these conditions, trans-resveratrol concentrations reached 237 mg/L, and for pallidol 114 mg/L. The comparison of different elicitation modes (different elicitors, combination with cyclodextrins or adsorbent resin) allowed to reach particularly high concentrations of target molecules: Resveratrol 6.14 g/L, pallidol 0.90 g/L, δ-viniferin 0.54 g/L, and ε-viniferin 0.50 g/L. Scale-up to 20 L-stirring-bioreactor gave similar growth rates to those observed in shake flask culture, with a high production of resveratrol (4.23 g/L) and δ-viniferin (0.76 g/L). This work provides new strategies for the production of stilbenes in plant cell suspension for biological and commercial evaluation. Full article

(This article belongs to the Special Issue Resveratrol in Plants)

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21 pages, 3718 KiB

Open AccessEditor’s ChoiceReview

Epigenetics Regulates Reproductive Development in Plants

by Qiang Han, Arthur Bartels, Xi Cheng, Angela Meyer, Yong-Qiang Charles An, Tzung-Fu Hsieh and Wenyan Xiao

Plants 2019, 8(12), 564; https://doi.org/10.3390/plants8120564 - 2 Dec 2019

Cited by 20 | Viewed by 8435

Abstract

Seed, resulting from reproductive development, is the main nutrient source for human beings, and reproduction has been intensively studied through genetic, molecular, and epigenetic approaches. However, how different epigenetic pathways crosstalk and integrate to regulate seed development remains unknown. Here, we review the [...] Read more.

Seed, resulting from reproductive development, is the main nutrient source for human beings, and reproduction has been intensively studied through genetic, molecular, and epigenetic approaches. However, how different epigenetic pathways crosstalk and integrate to regulate seed development remains unknown. Here, we review the recent progress of epigenetic changes that affect chromatin structure, such as DNA methylation, polycomb group proteins, histone modifications, and small RNA pathways in regulating plant reproduction. In gametogenesis of flowering plants, epigenetics is dynamic between the companion cell and gametes. Cytosine DNA methylation occurs in CG, CHG, CHH contexts (H = A, C, or T) of genes and transposable elements, and undergoes dynamic changes during reproduction. Cytosine methylation in the CHH context increases significantly during embryogenesis, reaches the highest levels in mature embryos, and decreases as the seed germinates. Polycomb group proteins are important transcriptional regulators during seed development. Histone modifications and small RNA pathways add another layer of complexity in regulating seed development. In summary, multiple epigenetic pathways are pivotal in regulating seed development. It remains to be elucidated how these epigenetic pathways interplay to affect dynamic chromatin structure and control reproduction. Full article

(This article belongs to the Section Plant Genetics, Genomics and Biotechnology)

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21 pages, 792 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Carotenoids in Cereal Food Crops: Composition and Retention throughout Grain Storage and Food Processing

by Daniela Trono

Plants 2019, 8(12), 551; https://doi.org/10.3390/plants8120551 - 28 Nov 2019

Cited by 55 | Viewed by 7745

Abstract

Carotenoids are C40 isoprenoids synthesized by plants, as well as some bacteria, fungi and algae, that have been reported to be responsible for a number of benefits conferred on human health. The inability of animals and humans to synthesize de novo these compounds [...] Read more.

Carotenoids are C40 isoprenoids synthesized by plants, as well as some bacteria, fungi and algae, that have been reported to be responsible for a number of benefits conferred on human health. The inability of animals and humans to synthesize de novo these compounds is the reason why they must be introduced from dietary sources. In cereal grains, carotenoids are important phytochemicals responsible for the characteristic yellow colour of the endosperm, which confers nutritional and aesthetic quality to cereal-based products. Cereals are staple foods for a large portion of the world population, and the biofortification of cereal grains with carotenoids may represent a simple way to prevent many human diseases and disorders. Unfortunately, evidence exists that the storage and processing of cereal grains into food products may negatively impact their carotenoid content; so, this loss should be taken into consideration when analysing the potential health benefits of the cereal-based products. Focusing on the recent updates, this review summarizes the chemical composition of the carotenoids in the grains of staple cereals, including wheat, maize, rice and sorghum, the main factors that affect their carotenoid content during storage and processing and the most fruitful strategies used improve the grain carotenoid content and limit the carotenoid post-harvest losses. Full article

(This article belongs to the Special Issue Carotenoid Biosynthesis, Regulation, Storage and Degradation in Plants)

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19 pages, 1207 KiB

Open AccessEditor’s ChoiceArticle

Polyphenol Compounds and Biological Activity of Caper (Capparis spinosa L.) Flowers Buds

by Aneta Wojdyło, Paulina Nowicka, Mar Grimalt, Pilar Legua, Maria Soledad Almansa, Asunción Amorós, Ángel Antonio Carbonell-Barrachina and Francisca Hernández

Plants 2019, 8(12), 539; https://doi.org/10.3390/plants8120539 - 25 Nov 2019

Cited by 47 | Viewed by 6525

Abstract

The aim of the study was to analyze potential health-promoting components of caper flower buds (Capparis spinosa L.) at six stages of development in two cultivars. Polyphenol compounds (flavonols, hydroxycinnamic acids, flavan-3-ols) were identified by Liquid Chromatography– quadrupole Time–of–Flight –Mass Spectrofotometer/Mass Spectrofotometer [...] Read more.

The aim of the study was to analyze potential health-promoting components of caper flower buds (Capparis spinosa L.) at six stages of development in two cultivars. Polyphenol compounds (flavonols, hydroxycinnamic acids, flavan-3-ols) were identified by Liquid Chromatography– quadrupole Time–of–Flight –Mass Spectrofotometer/Mass Spectrofotometer (LC-qTOF-MS/MS) and quantified by Ultra Performance Liquid Chromatography–Photodiode Array-Fluorescence Detector (UPLC-PDA-FL). Moreover, antioxidant properties (ABTS+•, FRAP, and ORAC), anti-diabetic potential (α-amylase and α-glucosidase), and anti-aging activity (acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)) of the buds were examined. Total phenolic compounds in the investigated caper varied from 10,720 to 3256 mg/100 g dry weight (DW), and depended on a genotype and growing stage of caper flowers. Among six different growing stages, the one named ‘nonpareilles’ was characterized by significantly higher content of polyphenols than the remaining five stages. The flavonols in caper flowers represented a mixture of different glycosylated quercetin, kaempferol, myricetin, and isorhamnetin derivatives, accounting for 38%–67%, 15%–36%, 4%–7%, and 0.8%–3%, respectively, of total flavonols,. Their contents strongly depended on the growth stage. ‘Nonpareilles’ and ‘surfines’ were richer in flavonols than ‘fines’ and ‘gruesas’. Of the six investigated growth stages, ‘nonpareilles’ accumulated the greatest amounts of bioactive compounds that correlated with antioxidant and anti-diabetic properties, and were more potent BuChE than AChE inhibitors. Full article

(This article belongs to the Section Phytochemistry)

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15 pages, 614 KiB

Open AccessEditor’s ChoiceArticle

First Report on Evaluation of Basic Nutritional and Antioxidant Properties of Moringa Oleifera Lam. from Caribbean Island of Saint Lucia

by Jozef Fejér, Ivan Kron, Vito Pellizzeri, Mária Pľuchtová, Adriana Eliašová, Luca Campone, Teresa Gervasi, Giovanni Bartolomeo, Nicola Cicero, Andrea Babejová, Mária Konečná, Vincent Sedlák, Janka Poráčová and Daniela Gruľová

Plants 2019, 8(12), 537; https://doi.org/10.3390/plants8120537 - 23 Nov 2019

Cited by 33 | Viewed by 6185

Abstract

Moringa oleifera Lam. has been considered as a multipurpose tree. The studies on it focus on its variable nutritional benefits. It is growing in many regions, but information about nutritional properties of those growing in the Caribbean is missing. The present study focused [...] Read more.

Moringa oleifera Lam. has been considered as a multipurpose tree. The studies on it focus on its variable nutritional benefits. It is growing in many regions, but information about nutritional properties of those growing in the Caribbean is missing. The present study focused on biochemical analysis of main nutritional and antioxidant properties in plant material—dried leaves and seeds—of Moringa oleifera. The composition of lipids, proteins, and vitamin E was evaluated in powdered dried leaves and seeds. Fatty acids were evaluated in oil extracted from the moringa seeds. Potential antioxidant properties of the moringa were evaluated in extract from crushed and powdered leaves, as well as from the powdered seeds. The total amounts of lipids, proteins, and vitamin E were higher in powdered seeds (31.85%, 35.13%, and 220.61 mg/kg) than in powdered leaves (12.48%, 20.54%, and 178.10 mg/kg). The main compound of fatty acids presented oleic acid (76.78%) in seeds’ oil and oleic (25.01%), palmitic (24.84%), and linolenic (24.71%) acids in leaves. Neohesperidin (126.8 mg/kg), followed by chlorogenic acid (99.96 mg/kg) and quercetin (43.44 and 21.44 mg/kg) were main phenolic compounds identified. Total phenols in powdered leaves’ extract (635.6 mg GAE/L) was higher than in powdered seeds’ extract (229.5 mg GAE/L). The activity against superoxide radical and hydroxyl radical was 92.4% and 73.1% by leaves’ powder extract and 83.6% and 60.7% by crushed-leaf extract; seed-powder extract exhibited a pro-oxidation activity (−68.4%) against superoxide radical and the lowest antioxidant effect against the hydroxyl radical (55.0%). Full article

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15 pages, 623 KiB

Open AccessEditor’s ChoiceArticle

Plant-Based Biostimulants Influence the Agronomical, Physiological, and Qualitative Responses of Baby Rocket Leaves under Diverse Nitrogen Conditions

by Ida Di Mola, Lucia Ottaiano, Eugenio Cozzolino, Mauro Senatore, Maria Giordano, Christophe El-Nakhel, Adriana Sacco, Youssef Rouphael, Giuseppe Colla and Mauro Mori

Plants 2019, 8(11), 522; https://doi.org/10.3390/plants8110522 - 19 Nov 2019

Cited by 88 | Viewed by 5719

Abstract

Nitrogen is the primary technical means responsible for food production increase, but on the other hand, wise management is needed because its excessive use can have a negative impact on the environment and on green leafy vegetable quality, such as that rocket. Rocket [...] Read more.

Nitrogen is the primary technical means responsible for food production increase, but on the other hand, wise management is needed because its excessive use can have a negative impact on the environment and on green leafy vegetable quality, such as that rocket. Rocket has the characteristics of accumulating nitrate in leaves with possible impacts on human health. In order to overcome this issue, researchers are focusing their attention on the use of alternative means, such as plant biostimulant application. The scope of this study was to assess the effect of legume-derived protein hydrolysate(LDPH) and tropical plant extract(TPE), combined with various doses of nitrogen (0 kg ha⁻¹ non-fertilized; N0); 60 kg ha⁻¹ (sub-optimal; N1); 80 kg ha⁻¹ (optimal; N2); and 100 kg ha⁻¹ (supra-optimal; N3)), in order to reduce nitrogen use, boost yield, and enhance the chemical and nutritional value of leaves without significantly accumulating nitrate. Both vegetal-based plant biostimulants enhanced plant growth, boosted the marketable yield (especially at N0 and N1 levels, by 38.2% and 28.2%, respectively, compared to the non-treated control), and increased the SPAD (Soil Plant Analysis Development) index and leaf pigments content, such as chlorophyll and carotenoids, especially in treated-LDPH rocket. The plant-based biostimulants also produced a major amplification in lipophilic antioxidant activity (+ 48%) and total ascorbic acid content (average + 95.6%), especially at low nitrogen fertilization levels, and maintained nitrate content under the legal European Comission limits. Full article

(This article belongs to the Special Issue Factors Affecting Yield, Quality, Antioxidants, Mineral Composition and Residual Biomass Valorization of Vegetable Crops)

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11 pages, 816 KiB

Open AccessEditor’s ChoiceReview

Glyphosate: Its Environmental Persistence and Impact on Crop Health and Nutrition

by Ramdas Kanissery, Biwek Gairhe, Davie Kadyampakeni, Ozgur Batuman and Fernando Alferez

Plants 2019, 8(11), 499; https://doi.org/10.3390/plants8110499 - 13 Nov 2019

Cited by 157 | Viewed by 24558

Abstract

Glyphosate-based herbicide products are the most widely used broad-spectrum herbicides in the world for postemergent weed control. There are ever-increasing concerns that glyphosate, if not used judiciously, may cause adverse nontarget impacts in agroecosystems. The purpose of this brief review is to present [...] Read more.

Glyphosate-based herbicide products are the most widely used broad-spectrum herbicides in the world for postemergent weed control. There are ever-increasing concerns that glyphosate, if not used judiciously, may cause adverse nontarget impacts in agroecosystems. The purpose of this brief review is to present and discuss the state of knowledge with respect to its persistence in the environment, possible effects on crop health, and impacts on crop nutrition. Full article

(This article belongs to the Section Plant Protection and Biotic Interactions)

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12 pages, 1972 KiB

Open AccessEditor’s ChoiceArticle

Highly Predictive Genetic Markers Distinguish Drug-Type from Fiber-Type Cannabis sativa L

by Fidelia Cascini, Alessio Farcomeni, Daniele Migliorini, Laura Baldassarri, Ilaria Boschi, Simona Martello, Stefano Amaducci, Luigi Lucini and Jamila Bernardi

Plants 2019, 8(11), 496; https://doi.org/10.3390/plants8110496 - 12 Nov 2019

Cited by 32 | Viewed by 5960

Abstract

Genetic markers can be used in seeds and in plants to distinguish drug-type from fiber-type Cannabis Sativa L. varieties even at early stages, including pre-germination when cannabinoids are not accumulated yet. With this aim, this paper reports sequencing results for tetrahydrocannabinolic acid synthase [...] Read more.

Genetic markers can be used in seeds and in plants to distinguish drug-type from fiber-type Cannabis Sativa L. varieties even at early stages, including pre-germination when cannabinoids are not accumulated yet. With this aim, this paper reports sequencing results for tetrahydrocannabinolic acid synthase (THCAS) and cannabidiolic acid synthase (CBDAS) genes from 21 C. sativa L. varieties. Taking into account that THCAS- and CBDAS-derived enzymes compete for the same substrate, the novelty of this work relies in the identification of markers based on both THCAS and CBDAS rather than THCAS alone. Notably, in our panel, we achieved an adequate degree of discrimination (AUC 100%) between drug-type and fiber-type cannabis samples. Our sequencing approach allowed identifying multiple genetic markers (single-nucleotide polymorphisms—SNPs—and a deletion/insertion) that effectively discriminate between the two subgroups of cannabis, namely fiber type vs. drug type. We identified four functional SNPs that are likely to induce decreased THCAS activity in the fiber-type cannabis plants. We also report the finding on a deletion in the CBDAS gene sequence that produces a truncated protein, possibly resulting in loss of function of the enzyme in the drug-type varieties. Chemical analyses for the actual concentration of cannabinoids confirmed the identification of drug-type rather than fiber-type genotypes. Genetic markers permit an early identification process for forensic applications while simplifying the procedures related to detection of therapeutic or industrial hemp. Full article

(This article belongs to the Section Plant Genetics, Genomics and Biotechnology)

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22 pages, 6398 KiB

Open AccessEditor’s ChoiceReview

Plant Disease Detection and Classification by Deep Learning

by Muhammad Hammad Saleem, Johan Potgieter and Khalid Mahmood Arif

Plants 2019, 8(11), 468; https://doi.org/10.3390/plants8110468 - 31 Oct 2019

Cited by 468 | Viewed by 75419

Abstract

Plant diseases affect the growth of their respective species, therefore their early identification is very important. Many Machine Learning (ML) models have been employed for the detection and classification of plant diseases but, after the advancements in a subset of ML, that is, [...] Read more.

Plant diseases affect the growth of their respective species, therefore their early identification is very important. Many Machine Learning (ML) models have been employed for the detection and classification of plant diseases but, after the advancements in a subset of ML, that is, Deep Learning (DL), this area of research appears to have great potential in terms of increased accuracy. Many developed/modified DL architectures are implemented along with several visualization techniques to detect and classify the symptoms of plant diseases. Moreover, several performance metrics are used for the evaluation of these architectures/techniques. This review provides a comprehensive explanation of DL models used to visualize various plant diseases. In addition, some research gaps are identified from which to obtain greater transparency for detecting diseases in plants, even before their symptoms appear clearly. Full article

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13 pages, 1584 KiB

Open AccessEditor’s ChoiceArticle

Improvement of Phenolic Compounds, Essential Oil Content and Antioxidant Properties of Sweet Basil (Ocimum basilicum L.) Depending on Type and Concentration of Selenium Application

by Liubov Skrypnik, Anastasia Novikova and Elina Tokupova

Plants 2019, 8(11), 458; https://doi.org/10.3390/plants8110458 - 29 Oct 2019

Cited by 63 | Viewed by 6970

Abstract

The effect of selenium biofortification on phytomass yield, selenium, essential oil and phenolic compounds content as well as antioxidant properties of basil leaves was investigated. Selenium in form of sodium selenate was applied either in nutrient solution or by foliar spraying at three [...] Read more.

The effect of selenium biofortification on phytomass yield, selenium, essential oil and phenolic compounds content as well as antioxidant properties of basil leaves was investigated. Selenium in form of sodium selenate was applied either in nutrient solution or by foliar spraying at three levels (2.0, 5.0 and 10.0 μM). Selenium treatment significantly increased Se concentration in leaves up to 20.23 μg g⁻¹ (addition in nutrient solution) and 10.74 μg g⁻¹ (foliar application). Neither a toxic nor a beneficial effect of Se addition on the plants was observed. Se application of 2 µM Se in nutrient solution and of 5 µM Se by foliar spraying successfully enhanced production of essential oils, hydroxycinnamic acids, total phenolics and antioxidant activity of basil leaves. The anthocyanin content was positively affected only by application of Se in nutrient solution. Considering both an increase in the Se concentration in basil leaves and an increase in the production of phytonutrients, the optimal doses of selenium can be considered to be 5 and 10 μM for Se addition in nutrient solution and by foliar treatment, respectively. The results confirm the possibility of the enrichment of basil plants with selenium and thereby improving the nutritional qualities of the human diet. Full article

(This article belongs to the Special Issue Selenium Metabolism and Accumulation in Plants)

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11 pages, 1060 KiB

Open AccessEditor’s ChoiceReview

Silicon and Plant Natural Defenses against Insect Pests: Impact on Plant Volatile Organic Compounds and Cascade Effects on Multitrophic Interactions

by Nicolas Leroy, Félix de Tombeur, Yseult Walgraffe, Jean-Thomas Cornélis and François J. Verheggen

Plants 2019, 8(11), 444; https://doi.org/10.3390/plants8110444 - 23 Oct 2019

Cited by 50 | Viewed by 10591

Abstract

Environmental factors controlling silicon (Si) accumulation in terrestrial plant are key drivers to alleviate plant biotic stresses, including insect herbivory. While there is a general agreement on the ability of Si-enriched plant to better resist insect feeding, recent studies suggest that Si also [...] Read more.

Environmental factors controlling silicon (Si) accumulation in terrestrial plant are key drivers to alleviate plant biotic stresses, including insect herbivory. While there is a general agreement on the ability of Si-enriched plant to better resist insect feeding, recent studies suggest that Si also primes biochemical defense pathways in various plant families. In this review, we first summarize how soil parameters and climate variables influence Si assimilation in plants. Then, we describe recent evidences on the ability of Si to modulate plant volatile emissions, with potential cascade effects on phytophagous insects and higher trophic levels. Even though the mechanisms still need to be elucidated, Si accumulation in plants leads to contrasting effects on the levels of the three major phytohormones, namely jasmonic acid, salicylic acid and ethylene, resulting in modified emissions of plant volatile organic compounds. Herbivore-induced plant volatiles would be particularly impacted by Si concentration in plant tissues, resulting in a cascade effect on the attraction of natural enemies of pests, known to locate their prey or hosts based on plant volatile cues. Since seven of the top 10 most important crops in the world are Si-accumulating Poaceae species, it is important to discuss the potential of Si mobility in soil-plant systems as a novel component of an integrated pest management. Full article

(This article belongs to the Special Issue The Role of Silicon in Plant Defences)

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19 pages, 1857 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Coordination of Leaf Development Across Developmental Axes

by James W. Satterlee and Michael J. Scanlon

Plants 2019, 8(10), 433; https://doi.org/10.3390/plants8100433 - 22 Oct 2019

Cited by 26 | Viewed by 10616

Abstract

Leaves are initiated as lateral outgrowths from shoot apical meristems throughout the vegetative life of the plant. To achieve proper developmental patterning, cell-type specification and growth must occur in an organized fashion along the proximodistal (base-to-tip), mediolateral (central-to-edge), and adaxial–abaxial (top-bottom) axes of [...] Read more.

Leaves are initiated as lateral outgrowths from shoot apical meristems throughout the vegetative life of the plant. To achieve proper developmental patterning, cell-type specification and growth must occur in an organized fashion along the proximodistal (base-to-tip), mediolateral (central-to-edge), and adaxial–abaxial (top-bottom) axes of the developing leaf. Early studies of mutants with defects in patterning along multiple leaf axes suggested that patterning must be coordinated across developmental axes. Decades later, we now recognize that a highly complex and interconnected transcriptional network of patterning genes and hormones underlies leaf development. Here, we review the molecular genetic mechanisms by which leaf development is coordinated across leaf axes. Such coordination likely plays an important role in ensuring the reproducible phenotypic outcomes of leaf morphogenesis. Full article

(This article belongs to the Special Issue From Genes to Shape and Function: Leaf Morphogenesis at Play)

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16 pages, 888 KiB

Open AccessEditor’s ChoiceReview

Potassium in Root Growth and Development

by Marek Sustr, Ales Soukup and Edita Tylova

Plants 2019, 8(10), 435; https://doi.org/10.3390/plants8100435 - 22 Oct 2019

Cited by 143 | Viewed by 12780

Abstract

Potassium is an essential macronutrient that has been partly overshadowed in root science by nitrogen and phosphorus. The current boom in potassium-related studies coincides with an emerging awareness of its importance in plant growth, metabolic functions, stress tolerance, and efficient agriculture. In this [...] Read more.

Potassium is an essential macronutrient that has been partly overshadowed in root science by nitrogen and phosphorus. The current boom in potassium-related studies coincides with an emerging awareness of its importance in plant growth, metabolic functions, stress tolerance, and efficient agriculture. In this review, we summarized recent progress in understanding the role of K⁺ in root growth, development of root system architecture, cellular functions, and specific plant responses to K⁺ shortage. K⁺ transport is crucial for its physiological role. A wide range of K⁺ transport proteins has developed during evolution and acquired specific functions in plants. There is evidence linking K⁺ transport with cell expansion, membrane trafficking, auxin homeostasis, cell signaling, and phloem transport. This places K⁺ among important general regulatory factors of root growth. K⁺ is a rather mobile element in soil, so the absence of systemic and localized root growth response has been accepted. However, recent research confirms both systemic and localized growth response in Arabidopsis thaliana and highlights K⁺ uptake as a crucial mechanism for plant stress response. K⁺-related regulatory mechanisms, K⁺ transporters, K⁺ acquisition efficiency, and phenotyping for selection of K⁺ efficient plants/cultivars are highlighted in this review. Full article

(This article belongs to the Special Issue Root System Structure and Function: A Themed Issue in Honor of Professor Yoav Waisel)

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13 pages, 641 KiB

Open AccessEditor’s ChoiceReview

Heterophylly: Phenotypic Plasticity of Leaf Shape in Aquatic and Amphibious Plants

by Gaojie Li, Shiqi Hu, Hongwei Hou and Seisuke Kimura

Plants 2019, 8(10), 420; https://doi.org/10.3390/plants8100420 - 16 Oct 2019

Cited by 55 | Viewed by 18720

Abstract

Leaves show great diversity in shape, size, and color in nature. Interestingly, many plant species have the ability to alter their leaf shape in response to their surrounding environment. This phenomenon is termed heterophylly, and is thought to be an adaptive feature to [...] Read more.

Leaves show great diversity in shape, size, and color in nature. Interestingly, many plant species have the ability to alter their leaf shape in response to their surrounding environment. This phenomenon is termed heterophylly, and is thought to be an adaptive feature to environmental heterogeneity in many cases. Heterophylly is widespread among land plants, and is especially dominant in aquatic and amphibious plants. Revealing the mechanisms underlying heterophylly would provide valuable insight into the interaction between environmental conditions and plant development. Here, we review the history and recent progress of research on heterophylly in aquatic and amphibious plants. Full article

(This article belongs to the Special Issue From Genes to Shape and Function: Leaf Morphogenesis at Play)

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16 pages, 351 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Non-Target-Site Resistance to Herbicides: Recent Developments

by Mithila Jugulam and Chandrima Shyam

Plants 2019, 8(10), 417; https://doi.org/10.3390/plants8100417 - 15 Oct 2019

Cited by 118 | Viewed by 7735

Abstract

Non-target-site resistance (NTSR) to herbicides in weeds can be conferred as a result of the alteration of one or more physiological processes, including herbicide absorption, translocation, sequestration, and metabolism. The mechanisms of NTSR are generally more complex to decipher than target-site resistance (TSR) [...] Read more.

Non-target-site resistance (NTSR) to herbicides in weeds can be conferred as a result of the alteration of one or more physiological processes, including herbicide absorption, translocation, sequestration, and metabolism. The mechanisms of NTSR are generally more complex to decipher than target-site resistance (TSR) and can impart cross-resistance to herbicides with different modes of action. Metabolism-based NTSR has been reported in many agriculturally important weeds, although reduced translocation and sequestration of herbicides has also been found in some weeds. This review focuses on summarizing the recent advances in our understanding of the physiological, biochemical, and molecular basis of NTSR mechanisms found in weed species. Further, the importance of examining the co-existence of TSR and NTSR for the same herbicide in the same weed species and influence of environmental conditions in the altering and selection of NTSR is also discussed. Knowledge of the prevalence of NTSR mechanisms and co-existing TSR and NTSR in weeds is crucial for designing sustainable weed management strategies to discourage the further evolution and selection of herbicide resistance in weeds. Full article

(This article belongs to the Special Issue Herbicide Resistance in Plants)

28 pages, 1259 KiB

Open AccessEditor’s ChoiceReview

Transcription Factors Associated with Leaf Senescence in Crops

by Sofia Bengoa Luoni, Francisco H. Astigueta, Salvador Nicosia, Sebastian Moschen, Paula Fernandez and Ruth Heinz

Plants 2019, 8(10), 411; https://doi.org/10.3390/plants8100411 - 14 Oct 2019

Cited by 49 | Viewed by 7770

Abstract

Leaf senescence is a complex mechanism controlled by multiple genetic and environmental variables. Different crops present a delay in leaf senescence with an important impact on grain yield trough the maintenance of the photosynthetic leaf area during the reproductive stage. Additionally, because of [...] Read more.

Leaf senescence is a complex mechanism controlled by multiple genetic and environmental variables. Different crops present a delay in leaf senescence with an important impact on grain yield trough the maintenance of the photosynthetic leaf area during the reproductive stage. Additionally, because of the temporal gap between the onset and phenotypic detection of the senescence process, candidate genes are key tools to enable the early detection of this process. In this sense and given the importance of some transcription factors as hub genes in senescence pathways, we present a comprehensive review on senescence-associated transcription factors, in model plant species and in agronomic relevant crops. This review will contribute to the knowledge of leaf senescence process in crops, thus providing a valuable tool to assist molecular crop breeding. Full article

(This article belongs to the Special Issue Leaf Senescence)

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