Horticulturae, Volume 10, Issue 7 (July 2024) – 71 articles

The popularity of ready-to-eat (RTE) salads has prompted novel technology to prolong the shelf life of their ingredients. Fresh-cut romaine lettuce is widely used in RTE salads; however, its tendency to quickly discolor continues to be a challenge for the industry. Selecting the ideal lettuce accessions for use in RTE salads is essential to ensure maximum shelf life, and it is critical to have a practical way to assess and compare the quality of multiple lettuce accessions that are being considered for use in fresh-cut applications. Thus, in this work we aimed to determine whether a computer vision system (CVS) composed of image acquisition, processing, and analysis could be effective to detect visual quality differences among 16 accessions of fresh-cut romaine lettuce during postharvest storage. The CVS involved a post-capturing color correction, effective image segmentation, and calculation of a browning index, which was tested as a predictor of quality and shelf life of fresh-cut romaine lettuce. The results demonstrated that machine vision software can be implemented to replace or supplement the scoring of a trained panel and instrumental quality measurements. Overall visual quality, a key sensory parameter that determines food preferences and consumer behavior, was highly correlated with the browning index, with a Pearson correlation coefficient of −0.85. Other important sensory decision parameters were also strongly or moderately correlated with the browning index, with Pearson correlation coefficients of −0.84 for freshness, 0.79 for off odor, and 0.57 for browning. The ranking of the accessions according to quality acceptability from the sensory evaluation produced a similar pattern to those obtained with the CVS. This study revealed that multiple lettuce accessions can be effectively benchmarked for their performance as fresh-cut sources via a CVS-based method. Future opportunities and challenges in using machine vision image processing to predict consumer preferences for RTE salad greens is also discussed. Full article

To achieve high-density tomato seedlings in a plant factory with artificial lighting, tomatoes (Solanum lycopersicum Mill. cv. “Zhongza NO.9”) were used as the experimental material. This study expected to analyze the effects of light intensity (150, 200, 250, and 300 μmol·m⁻²·s⁻¹) and light time (12 and 14 h), as well as daily light integral (DLI, 10.80, 12.60, and 12.96 mol·m⁻²·d⁻¹) and sowing density (50, 72, and 105 holes per tray), on seedling quality. The results indicated that biomass accumulation, seedling quality, and energy use efficiency of seedlings significantly improved with an increase in DLI. At a DLI of 12.96 mol·m⁻²·d⁻¹, seedlings sown at a density of 72 holes per tray exhibited comparable growth characteristics and biomass accumulation to those sown at 50 holes per tray. However, under lower DLIs, seedlings at 50 holes per tray displayed superior growth morphology and seedling quality compared to those at 72 holes per tray. This indicates that increasing the DLI can partially mitigate the negative effects of higher sowing density on seedling quality. Light use efficiency (LUE) and energy use efficiency (EUE) were not significantly different between seedlings at 72 and 105 holes per tray but were higher than those at 50 holes per tray. Therefore, optimizing parameters such as DLI and sowing density can effectively enhance the seedling quality, spatial use efficiency, and light use efficiency in industrial seedling production. Based on the results of this study, a DLI of 12.96 mol·m⁻²·d⁻¹ (achieved with a light intensity of 300 μmol·m⁻²·s⁻¹ and a light time of 12 h) and sowing density of 72 holes per tray are recommended for cultivating high-quality tomato seedlings while reducing energy consumption. Full article

Abiotic stresses, such as water limitation, are significant limiting factors in basil production. One alternative to mitigate the harmful effects of this stress on plants is using plant growth regulators. This study’s objective is to evaluate different doses of plant regulators in basil under water deficiency conditions. A randomized block experimental design in a factorial scheme with two factors was used: the first factor referred to the water regimes of 50% and 100% stomatal conductance, the second to different doses of the plant regulator mixture: 0 mL L⁻¹ (control), 3 mL L⁻¹, 6 mL L⁻¹, 9 mL L⁻¹, and 12 mL L⁻¹. Each treatment consisted of 12 pots per repetition. Biometric parameters, chlorophyll a fluorescence, and gas exchange were analyzed. The plant regulator positively influenced basil plants under water deficiency, with the most pronounced effects observed at the 12 mL L⁻¹ dose: a 17% increase in the number of leaves, a fourfold increase in CO₂ assimilation and carboxylation efficiency, and a sevenfold increase in water use efficiency. Therefore, the application of plant regulators on basil is recommended to mitigate the negative effects of water stress, with the most significant results observed at a dose of 12 mL L⁻¹. Full article

Gaillardia pulchella Foug. is a widely studied plant because of its high pharmacological and ornamental value. The leaves of G. pulchella were used for inducing callus and subsequent plant regeneration as it is the primary source of phytocompounds. The purpose of the present investigation was to formulate an in vitro propagation method for Gaillardia by using leaf explants in MS (Murashige and Skoog) medium. The best callus induction was observed on high (2.0 mg/L) α-naphthalene acetic acid (NAA) and a low (0.5 mg/L) 6-benzylaminopurine (BAP) with callus induction frequency of 91.66%. The leaf callus also demonstrated high caulogenesis ability (95.83%), with an average 5.2 shoots/callus mass at 0.5 mg/L BAP and 2.0 mg/L NAA. Indole Acetic acid (IAA) at 1.0 mg/L had the maximum rooting percentage (79.17%) with 12.4 roots per shoot. Rooted plantlets were later transferred to greenhouse conditions, showing a survivability rate of 75–80%. The physiological parameters, i.e., phenolic compounds and the flavonoids’ level, in the DPPH assay were higher in leaves obtained in vitro compared to callus formed from leaves and field-obtained (mother) leaves. Gas chromatography–mass spectrometry (GC–MS) analysis of methanol extracts of leaves (in vivo and in vitro) and leaf callus presented a wide array of compounds. In callus extract, some 34 phytocompounds were identified. Some of them were 3-hydroxy-2,3-dihydromaltol (25.39%), isoamyl acetate (11.63%), palmitic acid (11.55%), 4-methyloxazole (7.54%), and 5-methoxypyrrolidin-2-one (7.49%). Leaves derived in vivo and in vitro had 45 and 28 phytocompounds, respectively, belonging to different classes like lignans, phenols, terpenoids, alkaloids and fatty acids, etc. Those findings demonstrated that the leaf derived callus and the leaves are the potential stable source of several compounds with medicinal importance. The developed protocol may provide an alternative source of compounds without affecting wild flora. Full article

Fluorinated cytokinins have emerged as promising alternatives to traditional cytokinins in Phalaenopsis plant tissue culture, offering enhanced stability and bioactivity. However, their metabolic fate and impact on endogenous cytokinin profiles remain largely unexplored. This study builds upon previous research to investigate the comparative metabolism of the traditional cytokinin 6-Benzylaminopurine (BA) with the successful alternatives 6-(3-fluorobenzylamino)purine (FmT) and 6-(3-fluorobenzylamino)purine 9-riboside (FmTR). Additionally, this study examines the impact of another crucial factor, the use of ventilated versus closed containers, on metabolic processes. The results revealed the distinct metabolic profiles associated with each treatment, highlighting the complex interplay between exogenous and endogenous cytokinin levels. This study is the first to investigate the effects of these stable, synthetic, and exogenous cytokinins on the naturally occurring cytokinin levels and their metabolites in micropropagated Phalaenopsis. Additionally, we proposed an alternative inactivation pathway involving the conversion of FmTR and BA to pT and pTR. These findings provide valuable insights into the intricate relationship between cytokinin metabolism and plant growth under in vitro conditions. Full article

Over two billion people worldwide suffer from micronutrient deficiencies. Biofortifying vegetables can enhance micronutrient intake through the diet. This study assessed the biofortification of indoor-grown baby-leaf lettuce using aeroponics. Four experiments, two each, were conducted by adding different concentrations of Zn (from 10 to 450 µM) or Cu (from 3 to 250 µM) into a nutrient solution. A fifth experiment was conducted by simultaneously adding to the nutrient solution the optimal concentration of I (5 µM) and Se (13 µM), chosen on the basis of previous works, and the optimal concentration of Zn (250 µM) and Cu (150 µM), chosen on the basis of the results obtained in the first four experiments. Leaf biomass, mineral concentrations, chlorophylls, carotenoids, phenols, flavonoids, nitrates, and antioxidant capacity were measured 21 days after transplanting. Higher concentrations of Cu, Zn, I, or Se in the nutrient solution led to an increase in their concentrations in lettuce leaves, without affecting the growth or leaf quality of lettuce plants. The simultaneous application of I with the other elements induced a higher accumulation in leaves compared to when I is applied alone. One hundred grams of lettuce leaves biofortified with Se, I, Cu, and Zn would provide the 6.1%, 35.3%, and 263.0% of Adequate Intake for Cu, Se, and I, respectively, and 4.5% of Population Reference Intake for Zn. Our results suggest that simultaneously biofortifying baby-leaf lettuce with these four minerals is a practical and convenient way to integrate these micronutrients into the diet without reducing the yield or quality of lettuce. Full article

This study aimed to evaluate the effects of fruit position, light exposure and fruit surface temperature (FST) on apple fruit colour development and fruit quality at harvest, including sunburn damage severity. This was achieved by undertaking two experiments in a high-density planting of the dark-red apple ANABP 01 in Tatura, Australia. In the 2020–2021 growing season an experiment was conducted to draw relationships between fruit position and fruit quality parameters. Here, sample fruit position and level of light exposure were respectively determined using a static LiDAR system and a portable quantum photosynthetically active radiation (PAR) sensor. At harvest the sample fruit were analysed for percentage red colour coverage, objective colour parameters (L*, a*, b*, hue angle and chroma), sunburn damage, fruit diameter (FD), soluble solids concentration (SSC), flesh firmness (FF) and starch pattern index (SPI). A second experiment was conducted in the 2021–2022 growing season and focused on how fruit shading, light exposure and the removal of ultraviolet (UV) radiation affected the FST, colour development and harvest fruit quality. Five treatments were distributed among sample fruit: fully shaded with aluminium umbrellas, shaded for one month and then exposed to sunlight until harvest, exposed for one month and then shaded until harvest, covered with a longpass UV filter and a control treatment. The development of colour in this dark-red apple cultivar was highly responsive to aspects of fruit position, and the intensity and quality of light exposure. The best-coloured fruit were exposed to higher quantities of PAR, exposed to both PAR and UV radiation simultaneously and located higher in the tree canopy. Fruit that were fully exposed to PAR and achieved better colour development also displayed higher FST and sunburn damage severity. Full article

A half-diallel cross study of seven melon inbred lines was carried out. The seven parents and their 21 F₁ hybrids were evaluated for precocity of maturity, average weight per fruit, and fruit quality (fruit size, rind thickness, and soluble solids). The Diallel analysis was investigated for breeding values of these melon genotypes via general and specific combining ability, relationships between general and specific combining ability, and heterosis for the evaluated traits. The analysis of variance of the traits evaluated indicated highly significant differences among genotypes, suggesting the presence of adequate genetic variation for breeding. Additive genetic effects were most important with respect to fruit weight, while genetic dominance and epistasis effects mainly controlled fruit quality traits (fruit size, rind thickness, and TSS). Parent 1 (P1) and parent 3 (P3) had significant positive general combining ability effects for fruit weight. Also, P3 had positive general combining ability effects for fruit length and diameter, and cavity diameter. P3 was found to show maximum significant GCA in the desirable direction for all the traits except for TSS. Evaluation of heterosis (%) revealed that hybrid P1 × P3 can be considered as the best-performing hybrid for average fruit weight, TSS, and precocity, which also exhibited the highest positive and significant SCA effect for these traits. These results suggested that, among the melon genotypes studied, there is the potential to generate superior new varieties in hybrid production. Full article

Hardy geranium is a popular ornamental plant with a high market demand. As a result, there is a strong need for continuous innovation to improve its ornamental qualities. Interspecific hybridization is a widely used technique for introducing desirable traits and creating new cultivars with added value. To explore the possibilities of creating novelty within the Geranium genus, we conducted 2438 interspecific crosses over three flowering seasons, resulting in the successful harvest of 445 seeds and the final production of 82 seedlings. Using embryo rescue increased the germination rate of a seedling from 0.17% to 1.01%. To validate the paternal genetic contribution in the new seedlings, we used amplified fragment length polymorphism (AFLP) to assess the proportion of uniquely inherited paternal markers in all seedlings. AFLP analysis confirmed that 54 of the 82 seedlings were indeed true hybrids (65.8% hybridization success rate). A morphological evaluation of the flowers and leaves, including flower diameter (mm), style length (mm), number of flowers, flowering period (weeks), and color of both flowers and leaves, provided further confirmation of the F1 hybrid status of the seedlings. The results of our interspecific breeding demonstrated the efficiency of interspecific hybridization in hardy geraniums and its potential to create distinctive and novel cultivars for the ornamental market. Full article

There is a high interest in utilizing natural bioactive products derived from plants as a substitute for synthetic chemicals in the industry. This research focuses on the phytochemical composition of essential oils (EOs) of Ammi visnaga L. and Trachyspermum ammi L and their insecticidal activity against Sitophilus oryzae (L.), a common pest found in stored cereals. The EOs were extracted through steam distillation and analyzed using gas chromatography coupled with mass spectrometry (GC-MS). The EOs of A. visnaga consisted of twenty-four components, with Abietadiene (41.23%) being the most abundant, followed by linalool (25.54%) and limonene (19.04%). On the other hand, the EOs of T. ammi consisted of twenty-eight main components, with isothymol being the most abundant (51.88%). The results revealed that the EOs of T. Ammi (DL₅₀ = 0.1 µL EOs/L of air) were more toxic than A. visnaga (0.38 µL EOs/L of air), with the toxicity varying based on doses and exposure periods. To further understand the molecular mechanisms underlying this activity, molecular docking and dynamic simulations were performed using the major chemical constituents of the oils. The simulation results indicated that the major compounds, Abietadiene and isothymol, interact with the catalytic sites of the target proteins, inhibiting acetylcholinesterase and chitin synthase. These interactions form energetically favorable systems that remain stable throughout the molecular dynamic period. This research provides valuable insights into the potential of these EOs as natural insecticides and highlights the importance of molecular modeling in understanding the biological activities of plant-derived compounds. Full article

In this study, we refine in vitro propagation techniques for Camellia sinensis using a machine learning approach to ascertain the influence of different shooting and rooting conditions on key growth metrics. This was achieved by applying random forest (RF), XGBoost, and multilayer perceptron (MLP) models to dissect the complexities of micropropagation and rooting processes. The research unveiled significant disparities in growth metrics under varying media conditions, underscoring the profound impact of media composition on plant development. The meticulous statistical analysis, employing ANOVA, highlighted statistically significant differences in growth metrics, indicating the critical role of media composition in optimizing growth conditions. Methodologically, the study utilized explants from 2–3-year-old tea plants, which underwent sterilization before being introduced to two distinct culture media for their micropropagation and rooting phases. Statistical analyses were conducted to evaluate the differences in growth outcomes between media, while machine learning models were employed to predict the efficacy of micropropagation and rooting based on various growth regulators. This approach allowed for a comprehensive evaluation of the model’s performance in simulating plant growth under different conditions, leveraging metrics like R², RMSE, and MAE. The findings from this study significantly advance the understanding of tea plant micropropagation, highlighting the utility of machine learning models in agricultural optimization. This research contributes to enhancing micropropagation strategies for the tea plant and exemplifies the transformative potential of integrating machine learning into plant science, paving the way for improved agricultural and horticultural practices. This interdisciplinary approach offers a novel perspective on optimizing in vitro propagation processes, contributing substantially to plant tissue culture and biotechnology. Full article

Sweet cherry grown under sustainable management produces highly valuable fruits, whose quality shows important biochemical and morphological changes during ripening. Research was carried out in Iasi (Romania), with the aim to assess the quality characteristics of the sweet cherry fruits of three cultivars (Van, Andreiaș, Margonia), grown in an inner or outer position inside the tree crown, at the pre-ripening or full ripeness phase. In 2022, the colour component a* showed higher values in cv. Van and Andreias red fruits and in an inner position, whereas the components L* and b* at the full ripeness phase were highest in cv. Margonia. The dry matter and total soluble solids contents increased from the pre-ripening to the full ripeness phase and were highest in cv. Van sweet cherry fruits; the DM of fruit from the outer part of crown was higher than that of fruit from the inner part at the pre-ripening phase. The content of phenolics was the highest in cv. Margonia fruits at the pre-ripening stage and in cv. Van at the full ripeness phase and higher in the inner tree crown zones. The cultivar Margonia generally showed the highest vitamin C content in both years and development phases. The yellow fruit cv. Margonia mostly showed the highest values of chlorophyll a and b. The fruit’s content of carotene, lycopene, and anthocyanins was generally the highest in the red fruits of cv. Andreias. The examined sweet cherry cultivars showed a high variability in fruit nutritional quality and proved to be a rich source of bioactive compounds with antioxidant potential. Full article

The export of trimmed coconuts necessitates controlling microbial growth and browning, often achieved through the use of sodium metabisulfite (SMS). However, SMS can elicit allergic reactions in operators. To address this concern, ultrafine bubble (UFBs) technology was applied to reduce the SMS concentration. Trimmed coconuts were dipped in either a 1.5% SMS solution or a combination of 1.5% SMS with UFBs (1.5% SMS-UFBs) and compared to coconuts dipped or not dipped in a 3% SMS solution. All treated coconuts were then wrapped with polyvinyl chloride (PVC) film and stored at 2–4 °C for 2 months, followed by transfer to storage at 8–10 °C for an additional 14 days. The results indicated that halving the SMS concentration, with or without UFB application, effectively controlled microbial growth and browning, comparable to using 3% SMS. No contamination of E. coli or Salmonella spp. was detected. The mesocarp whiteness, browning index, polyphenol oxidase (PPO) activity, and total phenolic content of coconuts treated with 1.5% SMS or 1.5% SMS-UFBs did not differ significantly from those dipped in 3% SMS solution (p > 0.05). Similarly, the quality of coconut water and coconut meat in SMS or SMS-UFB treatments did not show significant differences. In dry seasons, using 1.5% SMS with or without UFBs yielded comparable results to those obtained using 3% SMS. However, in wet seasons, the synergistic effects of UFBs on reducing microbial growth incidence were observed, similar to the impact achieved with 3% SMS, whereas 1.5% SMS alone did not inhibit microbial growth. Overall, UFB technology shows promise in reducing SMS concentration by 50% for trimmed young coconuts throughout the year. Full article

The development of branching plays a pivotal role in the cultivation of ornamental chrysanthemums, as it dictates the ultimate morphology and quality of the plants. Strigolactones (SLs) are associated with apical dominance to indirectly inhibit shoot branching. Chrysanthemum morifolium ‘Baltasar’ in this study was subjected to treatment with three hormones: auxin (IAA), 6-BA, and GR24. Following the exogenous application of GR24 and IAA, a significant reduction in both the length and quantity of lateral buds on chrysanthemums was observed. Additionally, there was a notable down-regulation in the expression levels of CmPIN1 (associated with auxin transport) and CmIPT3, which is involved in cytokinin (CK) synthesis. After the application of 6-BA, there was a significant increase in both the length and quantity of lateral buds on chrysanthemums. Subsequently, the separate application of IAA and 6-BA to C. morifolium ‘Baltasar’ notably induced the expression of CmMAX1, a gene involved in the biosynthesis of strigolactones, and CmSMXL6, a gene associated with the signaling pathway of SLs, suggesting a negative regulatory role for SLs and auxin in chrysanthemum lateral buds, while CK demonstrated positive regulation. Cloning and expression analysis of CmSMXL6, a member of the D53/SMXL gene family in chrysanthemum, revealed its up-regulation following GR24 treatment, peaking at 9 h. The overexpression of CmSMXL6 in Arabidopsis thaliana promoted increased numbers of primary and secondary branches. In transgenic lines, genes associated with SLs synthesis (AtMAX1, AtMAX2, and AtMAX3) exhibited varying degrees of down-regulation, while the branching-inhibitory gene AtBRC1 also displayed decreased expression levels. These findings suggest that CmSMXL6 plays a role in promoting branching. Full article

Arundo donax is widely used as an ornamental plant in landscape gardening because of its adaptability to varying degrees of waterlogged conditions. However, to date, little information is available about the adaptive mechanism of A. donax under waterlogging stress. The results showed that long-term mild waterlogging efficiently induced the formation of adventitious roots (ARs) and further promoted root aerenchyma development, and that the activity of antioxidant enzymes (SOD, POD, and CAT) in Ars also was greatly enhanced after waterlogging. At the transcriptomic level, the expression of genes related to apoptosis, the regulation of cell division, ethylene biosynthesis, alginate synthesis, auxin signaling pathways, and anaerobic respiration was mostly up-regulated after the occurrence of waterlogging stress but genes involved in the abscisic acid signaling pathways were partly down-regulated, which indicated a preferential and favorable transcriptional response in regulating adventitious root development. Taken together, this study definitely advances our knowledge of the morphological, physiological, and transcriptomic responses of A. donax under waterlogging stress and sheds new lights on its adaptive mechanisms. Full article

The high number of grapevine (Vitis vinifera L.) cultivars grown world-wide are described and identified according to detailed morphological and morphometric descriptor lists. The grapevine leaf is of utmost importance in characterization, despite its traits being very sensitive to environmental factors. In this study, the effect of irrigation/drought stress on the individual leaf morphology and morphometry of the ‘Hárslevelű’ grapevine (Vitis vinifera L.) cultivar was examined. To verify the effect of the applied irrigation methods (drip and subsoil irrigation) on the plant’s water status, water potential measurements were carried out during the 2022 season. The effect of the applied treatments on the vegetative growth was evaluated according to point quadrat and a multichannel LiDAR analysis in order to describe the width of the canopy area, row volume, and area coverage index. The individual leaf morphology was assessed via traditional morphometry and colorimetry. Our results showed that rainfed plants had a significantly lower stem ψ compared to the drip- and subsoil-irrigated plants at all examined dates. The point quadrat results indicate that the leaf layer number was significantly (p < 0.05) influenced by the position, while the treatment showed no effect on the leaf layer number. The leaf colorimetry showed a difference among the samples, as significant alterations were found in 28 out of the 32 examined color properties. Within the traditional morphometric analysis, 54 traits were evaluated, and 14 of the traits were significantly altered due to the different water management systems. Full article

Photoperiod is a pivotal regulatory factor in the flowering of Camellia oleifera Abel. (C. oleifera). GIGANTEA (GI) serves as a pivotal regulator, not only orchestrating the intricate circadian rhythm but also governing photoperiod-dependent flowering. In order to explore the function of GI in C. oleifera (CoGI), we obtained a CoGI gene-coding sequence and analyzed a CoGI protein sequence using bioinformatics. Furthermore, we conducted a spatiotemporal expression analysis of CoGI. And a yeast two-hybridization assay was used to screen the interacting proteins of CoGI. Evolutionary analysis revealed high conservation of the CoGI protein, which clustered with the GI protein from Camellia sinensis (CsGI) on a common evolutionary branch. The expression of CoGI was different in each part, and a tissue expression analysis revealed that the relative expression level of the CoGI gene is highest in the leaves of C. oleifera, while it is at its lowest in the seed coats. Transgenic Arabidopsis thaliana (Arabidopsis) overexpressing CoGI exhibited early flowering under long-day conditions. In addition, the yeast two-hybrid library screening revealed interactions between seven C. oleifera proteins and CoGI: CoACR9, CoLAO, CoDExH12-like, CoIT1K-like, CoUPF0481, CoIDM3, and CoAt4g27190-like. The findings demonstrated that CoGI is crucial to C. oleifera’s flowering. Full article

Zanthoxylum planispinum is a type of plant with homologous properties in medicine and food, making it well-loved in China. To explore the development of the Z. planispinum field over the past 20 years, its research hotspots and frontier trends were analyzed. This study conducted database-based visualization analyses and knowledge graph analyses using CiteSpace software with data concerning Z. planispinum published in the Chinese National Knowledge Infrastructure and Web of Science databases between 2003 and 2023. Over the last 20 years, the number of Chinese and English publications on Z. planispinum has shown increasing trends. The foci of this research were mainly germplasm resources, cultivation management, seed oil extraction technology, flavonoid extraction technology, and correlation analyses of antioxidant activities. The main research frontiers included the unified standard naming and adaptation mechanisms of Z. germplasm resources, orientation cultivation, functional component extraction, processing technology research and development, and industrial chain construction. The results provide a scientific reference for the high-quality development of the prickly ash industry. Full article

The potential for grapes and wine to be tainted following vineyard exposure to wildfire smoke is well established, with recent studies suggesting hops and apples (and thus beer and cider) can be similarly affected. However, the susceptibility of other crops to ‘smoke taint’ has not yet been investigated. Smoke was applied to a selection of fruits and vegetables, as well as potted lavender plants, and their volatile phenol composition determined by gas chromatography–mass spectrometry to evaluate their susceptibility to contamination by smoke. Volatile phenols were observed in control (unsmoked) capsicum, cherry, lavender, lemon, spinach and tomato samples, typically at ≤18 µg/kg, but 52 µg/kg of guaiacol and 83–416 µg/kg of o- and m-cresol and 4-methylsyringol were detected in tomato and lavender samples, respectively. However, significant increases in volatile phenol concentrations were observed as a consequence of smoke exposure; with the highest volatile phenol levels occurring in smoke-exposed strawberry and lavender samples. Variation in the uptake of volatile phenols by different crops was attributed to differences in their physical properties, i.e., their surface area, texture and/or cuticle composition, while the peel of banana, lemon, and to a lesser extent apple samples, mitigated the permeation of smoke-derived volatile phenols into pulp. Results provide valuable insight into the susceptibility of different crops to smoke contamination. Full article

Citrus cultivars have various temperature needs for development and output at different times from flowering to harvesting, making climate one of the numerous factors that affect citrus’ productivity and quality. In this study, the yield and heat unit requirements for several commercial citrus species over several seasons from 2010/2011 to 2021/2022 in Egypt were investigated. For this investigation, the time of flowering and the time of fruit harvesting were recorded. However, the required heat units from flowering to fruit harvesting were calculated based on daily records of air temperature, taking into account that all results below zero (negative results) are not used and all maximum air temperatures above 35.0 °C (≥35.1) are changed to 35.0 °C. In addition, the base air temperature of 13.0 °C was utilized for determining the required heat units. The results showed that in the experimental area, the overall mean of minimum air temperature, maximum air temperature, air relative humidity, and precipitation during the experimental periods had values of 15.2 °C, 28.70 °C, 59.3%, and 0.3 mm/day, respectively. Moreover, the lowest number of days required from flowering to fruit harvesting was observed to be 290.0 days for Fremont mandarin. Furthermore, the highest number of days required from flowering to fruit harvesting was observed to be 482 and 440 days, respectively, for Bearss Seedless lime and Valencia orange. Our study has highlighted a notable diversity among the investigated citrus cultivars, particularly highlighting specific cultivars that possess high yield. The cultivar that shows the greatest yield over the investigated seasons of the study was Valencia orange with 147.6 kg/tree. Moreover, the average values of the heat unit requirements for Washington Navel orange, Valencia orange, Murcott mandarin, Fremont mandarin, and Bearss Seedless lime were 3112.7, 3628.3, 3221.9, 3027.6, and 4398.4 °C day, respectively. This is the first report regarding the heat unit’s determination for several citrus cultivars grown in Egypt, and we expect this research will provide a new awareness in accepting and discovering novel locations where citrus cultivars can be positively developed in Egypt. It will also prove to be a source of basic information for the development of the citrus crop model. Full article

There is a need for alternatives or complements to synthetic fertilizers to enhance agricultural sustainability. Applying organic amendments can play a significant role in this. Insect droppings show high potential, though studies evaluating their agronomic value have only recently begun to emerge. This study compared black soldier fly (Hermetia illucens L.) and mealworm (Tenebrio molitor L.) larvae frass with another organic amendment (Nutrimais) derived from composting forestry, agro-industrial, and domestic waste. The experiment also included ammonium nitrate at two rates [the same as the organic amendments, 50 kg ha⁻¹ nitrogen (N) (FullR), and half that rate (HalfR)] and an unfertilized control. The study spanned two growth cycles of lettuce (Lactuca sativa L.) grown in pots, followed by unfertilized oats (Avena sativa L.) to assess the residual effects of the fertilizing treatments. Mealworm larvae frass mineralized rapidly, with an apparent N recovery of 37.4% over the two lettuce growth cycles, indicating its high availability to soil heterotrophic microorganisms. The average dry matter yield (DMY) of lettuce was the highest among all treatments (12.8 and 9.8 g plant⁻¹ in the first and second lettuce cycles), even compared to the FullR treatment (12.2 and 7.8 g plant⁻¹), though without significant differences. Although mealworm larvae frass exhibited a high mineralization rate, the DMY cannot be attributed solely to N supply, as plants in the FullR treatment showed better N nutritional status. Mealworm larvae frass provided strong evidence of a plant biostimulant effect, not explained by the variables measured in this study. Black soldier fly larvae frass exhibited typical behavior of a moderately reactive organic amendment, while Nutrimais showed low reactivity, with a near-neutral mineralization/immobilization balance. The results suggest mealworm larvae frass is recommended for early maturing vegetable crops, whereas Nutrimais appears more suitable for perennial crops with low short-term nutrient requirements. Full article

Landraces are considered a crucial component of biodiversity conservation, serving as a reservoir of genetic diversity. Consequently, the collection, cultivation, and detailed characterization of such landraces constitute an inherent aspect of the world’s natural resource heritage. This effort holds promise for the development of elite varieties capable of thriving amidst continuous global climate fluctuations. In this context, we conducted a comprehensive assessment of the main agronomic attributes, physico-chemical properties, and functional quality traits of the major hot pepper landraces adapted to diverse climatic conditions in Tunisia. These landraces include ‘Dhirat’, ‘Semmane’, ‘Beldi’, ‘Nabeul’, ‘Jerid’, ‘Mahdia’, ‘Cayenne’, ‘Kairouan’, and ‘Baklouti’. Most of the pepper landraces exhibited satisfactory yields, ranging from 1163.25 to 1841.67 g plant⁻¹ in ‘Jerid’ and ‘Kairouan’, respectively, indicating robust productivity, especially under prevailing climatic changes and high temperatures during both growing cycles. The levels of antioxidants comprising capsaicinoids, carotenoids, phenolics, and tocopherols, as well as radical scavenging activity, emerged as key discriminating factors among pungent pepper landraces. Irrespective of genotype, capsaicin and dihydrocapsaicin constituted the major capsaicinoids, accounting for 44–91% of the total capsaicinoids content. Total capsaicinoids ranged from 1.81 µg g⁻¹ fw to 193.71 µg g⁻¹ fw, with ‘Baklouti’ and ‘Jerid’ identified as the most pungent landraces. Total carotenoids ranged from 45.94 µg g⁻¹ fw to 174.52 µg g⁻¹ fw, with ‘Semmane’ and ‘Jerid’ exhibiting the highest levels. Considerable variation was observed in β-carotene content, spanning from 3% to 24% of the total carotenoids. α-Tocopherol content ranged from 19.03 µg g⁻¹ fw in ‘Kairouan’ to 30.93 µg g⁻¹ fw in ‘Beldi’, exerting a notable influence on the overall tocopherol content. Conversely, the β- and γ-tocopherol isomers were detected at very low concentrations. The total vitamin C content ranged from 132 mg 100g⁻¹ fw in ‘Mahdia’ to 200 mg 100 g⁻¹ fw in ‘Nabeul’, indicating relatively low genetic variability. However, large variability was detected in total phenolics content, ranging from 168.58 mg GAE kg⁻¹ fw in ‘Beldi’ to 302.98 mg GAE kg⁻¹ fw in ‘Cayenne’. Landraces such as ‘Dhirat’, ‘Nabeul’, ‘Semmane’, ‘Kairouan’, ‘Cayenne’, and ‘Mahdia’ appear suitable for both fresh consumption and processing, owing to their favorable average fruit weight, soluble solids content, and bioactive content. Among the pepper landraces tested, ‘Cayenne’ achieved the highest value of radical scavenging activity in both hydrophilic and lipophilic fractions (RSAHF and RSALF), with variations ranging from 59% to 120% for RSAHF and from 4% to 63% for RSALF. This study aims to preserve and enhance the value of local genetic resources and contribute to identify desirable traits for incorporation into breeding programs to develop high-quality, high-yielding landraces and elite lines. Full article

Flourensia cernua and Jatropha dioica are non-timber forest species that grow in the desert regions of northern Mexico. Currently, they are recognized as a viable alternative to traditional remedies used to address certain ailments. However, the low yields of bioactive compounds obtained propitiate the use of more effective extraction techniques such as ultrasound-assisted extraction (UAE) in combination with statistical models such as Taguchi to maximize the yields of bioactive compounds. The objective of the research was to determine the optimal conditions for maximizing the yields of purified polyphenolic compounds from F. cernua and J. dioica using the Taguchi statistical model. In addition, we evaluated the total flavonoid content, antioxidant activity (ABTS•+, FRAP, and OH^• hydroxyl radical inhibition), and the in vitro evaluation of α-amylase inhibition and ex vivo hemolysis inhibition. Furthermore, a functional group analysis was conducted using FTIR. The optimization process revealed that the maximum yields of bioactive compounds for F. cernua and J. dioica were achieved with a particle size of 0.25 mm and 0.30 mm, temperatures of 60 °C for both, a water–ethanol concentration of 50% for both, and extraction times of 30 min and 5 min, respectively. The matrix bioactive compounds obtained contain flavonoid-type phenolic compounds, which exhibit properties such as inhibiting free radicals and acting as reducing agents; inhibiting α-amylase activity, which is involved in carbohydrate metabolism; and protecting red blood cells from damage by reactive oxygen species. Finally, the FTIR analysis allowed for the identification of functional groups associated with the polyphenolic compounds (O–H, C–H, C–C, C=O). These results suggest that both non-timber forest species are a rich source of bioactive compounds with potential for application in the agri-food and pharmaceutical industries However, it is necessary to carry out compound identification as well as toxicity analyses to guarantee the safety of these bioactive compounds. Full article

The high biological activity of cultivated and wild purslane offers broad possibilities for utilizing this plant in medicine and human nutrition. To assess the prospects of obtaining new functional food products based on the wild form of P. oleracea L., foliar biofortification of this species with sodium selenate (VI) was carried out, and the changes in leaf and seed biochemical characteristics were investigated. Selenium significantly enhanced plant yield, photosynthetic pigments and the ascorbic acid content, and showed a tendency to seed productivity increase. The application of selenium augmented quinic acid content in leaves by 1.7 times but did not affect the oxalic acid content. Oxalic acid prevailed in wild purslane and quinic acid in cultivated purslane (cv. Makovey). Seed oil in Se-enriched purslane was characterized by a two-fold decrease in saturated fatty acids and squalene and 2.3-fold decrease in malonic dialdehyde content, along with a 1.4-fold increase in ascorbic acid. Selenium supplementation resulted in an increase in total lipids and mono- and di-unsaturated fatty acids and did not affect the concentration of ω-3 fatty acids and sterol accumulation. Among the identified sterols, only the minor ones (fucosterol, 7-stigmasterol and ∆7-avenosterol) showed a slight decrease upon Se supply. Compared to seeds of cv. Makovey, wild purslane seeds had higher levels of antioxidant activity by a factor of 2 and of polyphenols by a factor of 3.2 but did not differ significantly in oil fatty acid composition. The results indicate the importance of wild purslane leaves/seeds both fortified and not fortified with Se in human nutrition and medicine. Full article

This study evaluated the effect of salicylic acid (SA) application on yield, fruit quality, and post-harvest storage in Prunus avium subjected to deficit irrigation (DI). A field experiment with six-year-old P. avium cv. Lapins was performed under two water treatments: irrigation at 100% of crop evapotranspiration (ETc) [full irrigation (FI)] and irrigation at 60% ETc from the second fruit phase to harvest time (DI). A single 0.5 mM SA was applied to both water treatments at fruit color change. At harvest time, fruits were collected to determine yield, fruit quality, and quality during post-harvest storage (0, 10, 20, and 30 days). The DI reduced fruit yield (11%), fruit weight (8%), and caliber (6%) and increased firmness (7%) and total soluble solids (TSS) (5%) in P. avium compared with FI plants at harvest time. Our study showed that SA application recovered fruit yield (9%), fruit weight (5%), and caliber (4%), improving TSS in DI plants at day 0. Interestingly, SA application significantly reduced P. avium fruit cracking (78% in FI and 82% in DI). Fruit weight was reduced in all treatments, mainly decreasing by 14% in FI and 13% in DI plants at day 30 of post-harvest storage. Fruit weight did not change during post-harvest storage with SA, except on day 30, where a slight reduction was observed. TSS showed no significant differences during post-harvest storage for all treatments. Therefore, SA could be an interesting tool to mitigate the impact of DI on the yield and fruit quality of P. avium and to reduce fruit cracking and prolong fruit quality during post-harvest storage. Full article

Sewage sludge can be used as an organic amendment as long as it is ensured that there is no risk of environmental contamination or risk to public health. In this study, sewage sludge from two wastewater treatment plants (WWTPs) subjected to two disinfection and stabilization treatments [40% (mass/mass), calcium oxide, and calcium hydroxide] and their respective untreated sewage sludge were used. Three control treatments were also added: conventional farmyard manure (FYM), a nitrogen (N) mineral fertilizer (ammonium nitrate 34.5% N) applied at a rate of 50 kg N ha⁻¹ (N50) (the same rate of all organic amendments), and an unfertilized control (N0), totaling nine treatments. Lettuce (Lactuca sativa L.) was cultivated in pots for two growing cycles. The dry matter yield (DMY) was higher in the N50 treatment (13.5 and 10.6 g plant⁻¹ in the first and second growing cycles, respectively), followed by sewage sludge (10.8 to 12.4 and 8.4 to 8.7 g plant⁻¹), FYM (8.5 and 7.2 g plant⁻¹), and the control (7.7 and 6.0 g plant⁻¹). The DMY was related to the N provided by the different treatments, assessed by the N and nitrate concentrations in tissues, N uptake, and apparent N recovery (ANR). Sewage sludge, due to its high N concentration and low carbon (C)/N ratio, mineralized rapidly, providing a significant amount of N to plants, as well as other nutrients, such as phosphorus (P) and boron (B). FYM, with a higher C/N ratio, provided less N to plants, also due to the short duration of the lettuce growing cycle. Alkalized sewage sludge increased soil pH and calcium (Ca) availability for plants. Fertilizer treatments minimally influenced cationic micronutrients. Heavy metals in the initial sewage sludge were below the threshold values established in international legislation, and the levels in soil and lettuce tissues were generally not higher than those in other treatments. Both of the sewage sludges used in this study showed high fertilizing value and very reactive behavior, making nutrients available much more quickly than FYM. This information is relevant to consider in defining their agricultural use. Full article

Climate change is currently the greatest threat to the environment as we know it today. The present study aimed to highlight the changes in the main climatic elements during the last five decades (1971–2020) in northeastern Romania (Copou-Iaşi wine-growing center) and their impact on grape quality, as part of precision viticulture strategies and efficient management of grapevine plantations. Data analysis revealed a constant and significant increase in the average air temperature in the last 50 years (+1.70 °C), more pronounced in the last 10 years (+0.61 °C), with a number of days with extreme temperatures (>30 °C) of over 3.5-fold higher, in parallel with a fluctuating precipitation regime. The increase in average temperatures in the last 40 years was highly correlated with the advancement of the grape harvest date (up to 12 days), a significant increase in Vitis vinifera L. white grape sugar concentration (+15–25 g/L), and a drastic decrease in total acidity (−2.0–3.5 g/L tartaric acid). The significant increase in the values of the bioclimatic indices require the reclassification of the wine-growing area in higher classes of favorability, raising the opportunity to grow cultivars that are more suited to warmer climates, ensuring the efficiency of the plantation, and meeting current consumer expectations. Full article

Ploidy identification is a basic method for determining germplasm resources and for breeding new varieties of oil-seed camellia. In this study, flow cytometry and K-mer analysis were used to identify the ploidy of oil-seed camellia germplasms. To determine the best tissue organ type, lysis time, and dyeing time, evaluation indices such as the presence of a clear main peak, the ease of sampling, and the coefficient of variation were used. A technique was established, and the ploidies of different oil-seed camellia germplasms were identified. The results showed that pollen was the best material and that using a 400 mL PI lysis solution for 10 min lysis, followed by dyeing with a 1600 mL DAPI dyeing solution for 10 min, was the most suitable technique. According to the peak value of the control diploid Camellia azalea, 15 samples were estimated to be diploid, 24 samples were tetraploid, 18 samples were hexaploid, and 13 samples were octoploid. In addition, the K-mer analysis results showed that among the five samples, CK, C051, and C047 were diploid, while C037 and C043 were tetraploid, results that are consistent with the results of the flow cytometry identification. This study is therefore valuable for the polyploid selection and use of different ploidy germplasm resources for the cross breeding of oil-seed camellia. Full article

The sclerotia of Wolfiporia hoelen (Fr.) Y.C. Dai & V. Papp is an important traditional Chinese medicine with diverse pharmacological properties. This study utilized a combination of PacBio Long-Read Sequencing, Illumina Short-Read Sequencing, and Hi-C Sequencing to generate a high-quality chromosome-level genome assembly of a W. hoelen strain Minling A5. There were 112 contigs in the genome, with 62.95 Mb in total length and 4.21 Mb in length for the contig N50. The average GC content was 51.89%. Based on Hi-C data, we corrected the CCS data and scaffolded them into 14 pseudo-chromosomes. The genome contained 44.37% repetitive sequences and 12,670 protein-coding genes, 86.53% (10,963) of which could be functionally annotated in at least one of the KOG, GO, Pfam, Swissprot, TrEMBL, NR, and KEGG databases. In addition, 240 transfer RNAs, 97 ribosomal RNAs, and 103 other non-coding RNAs were identified in the W. hoelen genome. A total of 755 pseudogenes were also identified, with an average length of 2665.51 bp. Further, there were 398, 100, 2837, 519, and 2068 genes annotated by CAZymes, TCDB, PHI, P450, and DFVF databases, respectively. One notable attribute of W. hoelen is its capacity to thrive in a substrate of fresh pine sawdust. Through an analysis of the growth on various pure wood sawdust culture media, we found that the growth of W. hoelen and Sparassis latifolia on pine sawdust was similar to that on broad-leaved wood sawdust, while the growth of Pleurotus ostreatus, P. eryngii, and Cyclocybe aegerita was slower than that on broad-leaved wood sawdust. By the functional annotation analysis of orthogroups in these five mushroom-forming fungi, it was determined that 645 orthogroups were specifically common in W. hoelen and S. latifolia. The genes in these specific orthogroups were significantly enriched in 12 pathways, including steroid biosynthesis, biosynthesis of antibiotics, and tyrosine metabolism. The high-quality genome and comparative genome analysis results significantly contribute to advancing our foundational knowledge of W. hoelen biology, while also offering valuable insights for the development of innovative biotechnological approaches aimed at enhancing the efficient and sustainable utilization of Pinus. Full article

Salinity poses a significant threat to agricultural productivity worldwide, with its detrimental effects on plant growth and physiological processes. Understanding the mechanisms by which plants respond to salt stress is crucial for developing strategies to mitigate its impact on crop yield and sustainability. To address this issue, a pot study was conducted to determine the effect of salt stress on the physiological and biochemical attributes of neem (Azdiarchta indica A. Juss). Plants were grown for 10 months in pots filled with soil having different salinity levels of 3, 6, 9, 12, 15, and 18 dS m⁻¹ and compared with a control of 1.7 dS m⁻¹. The results showed that plant growth and chlorophyll contents declined as salinity levels increased. Due to oxidative stress, the contents of H₂O₂ increased under higher salt levels. The mitigation of oxidative stress was achieved through the activation of antioxidant enzymes (catalase, ascorbate peroxidase, peroxidase, and superoxide dismutase). Multivariate analysis indicated that Na⁺ accumulation in plants was positively related to H₂O₂ production and enzymatic activities, and negatively related to plant biomass, chlorophyll contents, root and shoot K⁺ concentration, and root K⁺/Na⁺. The experimental results suggest that neem plants can be grown in moderate saline soils. Full article