Search Results (587)

Coconut yield and quality are significantly affected by multiple female inflorescences (MFF), which disrupt flower differentiation balance. To elucidate the molecular mechanisms, we compared MFF with normal female inflorescences (NFF) using phenotypic, morphological, physiological, and multi-omics approaches. The results revealed that MFF exhibited altered flower structures. MFF showed elevated iron (Fe), nitrogen (N), sulfur (S), potassium (K), calcium (Ca), zinc (Zn), proline (Pro), catalase (CAT), malondialdehyde (MDA), abscisic acid (ABA), and jasmonic acid (JA), but reduced molybdenum (Mo), soluble sugar (SS), soluble protein (SP), superoxide dismutase (SOD), peroxidase (POD), indole acetic acid (IAA), zeatin riboside (ZR), and gibberellic acid (GA). We detected 445 differentially expressed genes (DEGs) mainly enriched in ABA, ETH, BR, and JA pathways in MFF compared to NFF. We identified 144 differentially accumulated metabolites (DAMs) primarily in lipids and lipid-like molecules, phenylpropanoids and polyketides, as well as organic acids and derivatives in the comparison of MFF and NFF. Integrated analysis linked these to key pathways, e.g., “carbon metabolism”, “carbon fixation in photosynthetic organisms”, “phenylalanine, tyrosine, and tryptophan biosynthesis”, “glyoxylate and dicarboxylate metabolism”, “glycolysis/gluconeogenesis”, “pentose and glucuronate interconversions”, “flavonoid biosynthesis”, “flavone and flavonol biosynthesis”, “pyruvate metabolism”, and “citrate cycle (TCA cycle)”. Based on our results. the bHLH137, BHLH062, MYB (CSA), ERF118, and MADS2 genes may drive MFF formation. This study provides a framework for understanding coconut flower differentiation and improving yield. Full article

Soil salinity poses a critical threat to global agricultural productivity, exacerbating food security challenges in arid and semi-arid regions. This review synthesizes current knowledge on the physiological and biochemical impacts of salinity stress in plants, with a focus on the role of gibberellic acid (GA₃) in mitigating these effects. Salinity disrupts ion homeostasis, induces osmotic stress, and generates reactive oxygen species (ROS), leading to reduced chlorophyll content, impaired photosynthesis, and stunted growth across all developmental stages, i.e., from seed germination to flowering. Excess sodium (Na⁺) and chloride (Cl⁻) accumulation disrupts nutrient uptake, destabilizes membranes, and inhibits enzymes critical for carbon fixation, such as Rubisco. GA₃ emerges as a key regulator of salinity resilience, enhancing stress tolerance through various mechanisms like scavenging ROS, stabilizing photosynthetic machinery, modulating stomatal conductance, and promoting osmotic adjustment via osmolyte accumulation (e.g., proline). Plant hormone’s interaction with DELLA proteins and cross-talk with abscisic acid, ethylene, and calcium signaling pathways further fine-tune stress responses. However, gaps persist in understanding GA₃-mediated floral induction under salinity and its precise role in restoring photosynthetic efficiency. While exogenous GA₃ application improves growth parameters, its efficacy depends on the concentration- and species-dependent, with lower doses often proving beneficial and optimum doses potentially inhibitory. Field validation of lab-based findings is critical, given variations in soil chemistry and irrigation practices. Future research must integrate biotechnological tools (CRISPR, transcriptomics) to unravel GA₃ signaling networks, optimize delivery methods, and develop climate-resilient crops. This review underscores the urgency of interdisciplinary approaches to harness GA₃’s potential in sustainable salinity management, ensuring food security and safety in the rapidly salinizing world. Full article

This study aimed to develop seed-based mass propagation techniques for the conservation and horticultural and medicinal uses of Scrophularia koraiensis Nakai, an endemic plant in the Korean Peninsula. Seeds were collected from four different locations (accessions) and subjected to untreated (control), gibberellic acid (GA)-only treatment, cold stratification-only treatment, or a cold stratification + GA treatment. Except for seeds collected from one location, the control group exhibited low germination of below 20% in all other locations. However, the GA-only and cold stratification-only treatments released seed dormancy and promoted germination compared with the control. In particular, the cold stratification-only treatment at 5 °C for 4 weeks resulted in about 80% germination in all accessions and demonstrated positive effects on germination speed and uniformity. These findings indicated that S. koraiensis seeds exhibit non-deep physiological dormancy (PD). Upon comparing the seed dormancy classes across various species of Scrophularia, native to different continents and countries, we confirmed that PD is very well conserved in the genus Scrophularia. Therefore, the study outcomes will provide fundamental and practical insights into the seed dormancy and germination characteristics of various Scrophularia species for future studies. Full article

Cannabis is usually dioecious, with male and female flowers on separate plants. Cultivators prioritize the use of female plants because their flowers contain a higher density of glandular trichomes, the primary source of cannabinoids, compared to male flowers. Feminized seeds, which give rise exclusively to female plants, are highly valued in the cannabis industry. These seeds are produced by crossing a natural female plant with another female plant that has been masculinized to generate pollen. Masculinization is achieved by inhibiting ethylene and/or applying gibberellins prior to flower initiation in female plants. Currently, silver thiosulfate (STS) is the most common treatment used in the cannabis industry, though environmental concerns arise from silver applications. This study compared STS with three other ethylene-inhibiting agents: aminoethoxyvinylglycine (AVG), cobalt nitrate (CBN), and 1-methylcyclopropene (1-MCP). Some STS and CBN treatments also included gibberellic acid as a synergist. STS-treated plants displayed the most effective masculinization and pollen dispersal, compared to plants treated with AVG. Only STS and AVG generated sufficient pollen for collection. This pollen was initially tested for germination potential and subsequently stored for up to five weeks at 22.2 °C, 7.2 °C, or 1.1 °C.Germination rates ranged from 2.2% to 5.8%, underscoring the influence of storage conditions and highlighting the need to refine preservation methods to enhance agricultural viability. Pollen from plants treated with AVG remained viable for three weeks at 1.1 °C, although there were concerns about a high risk of phytotoxicity. STS-treated pollen also remained viable for three weeks at the same temperature. Neither CBN nor 1-MCP treatments were effective in inducing masculinization. No clear synergistic effect of gibberellic acid combined with STS or AVG was observed; however, growth stunting led to increased mortality. Due to pollen viability and phytotoxicity problems with AVG, STS remains the best treatment to masculinize female cannabis plants when breeding for feminized seeds. Full article

Seed dormancy is a key ecological attribute influencing germination timing and the ability of species to establish in variable environments. This study investigated whether inter-population variability in seed dormancy expression exists in Lonicera etrusca, a Mediterranean shrub known for producing seeds with underdeveloped embryos and multiple dormancy types. Seeds were collected from four geographically and ecologically distinct populations in central Iberia and subjected to a series of germination experiments simulating natural seasonal temperature regimes, stratification treatments, and gibberellic acid application. Across all populations, seeds exhibited morphological dormancy (MD) and varying degrees of morphophysiological dormancy (MPD), including non-deep simple and deep complex types. Despite high intra-specific variability in dormancy expression, no significant differences were found among populations for germination patterns or embryo growth responses. This indicates that dormancy variability is an intrinsic, conserved feature of the species rather than a locally adaptive trait. The homogenization of germination strategies across populations may be facilitated by bird-mediated seed dispersal, promoting gene flow and limiting local selection. These findings support the hypothesis that dormancy polymorphism in L. etrusca reflects a flexible germination strategy that enhances colonization potential across heterogeneous Mediterranean environments, rather than an environmentally induced plastic response. Full article

Within the context of sustainable exploitation of phytogenetic resources, the present study aimed to develop species-specific seed germination protocols for eighteen native and potentially underutilized plant species originating from northeastern Greece. The taxa were selected based on their antioxidant potential and their provenance to enhance their regional exploitation potential, thus utilizing the species’ local adaptation traits. To quantify the maximum germination potential in each case, seed viability was assessed using the tetrazolium (TTZ) test. The pre-treatments applied for seed dormancy release included cold stratification and the application of gibberellic acid (GA₃) and kinetin. Germination tests revealed that 9 of the 18 species exhibited high germination percentages in the control treatment (ranging between 64 and 90%) indicating that after-ripening was sufficient for any seed dormancy release in a significant portion of the seed lot. Furthermore, cold stratification and hormonal treatments significantly enhanced germination in seven species (final seed germination up to 85%), indicating deeper physiological dormancy and confirming the role of cold stratification and phytohormones in dormancy release. Two species showed no germination under any pre-treatment while viable, indicating the presence of more complex dormancy mechanisms. Germination percentages were frequently lower than the corresponding seed viability values, which ranged from 70% to 100%, suggesting that a portion of the seed lot exhibited deeper dormancy throughout. The results showcased species with favorable germination patterns, thus successfully identifying species that can be readily propagated, as well as species that require specific pre-treatments. The study sets the basis for domestication and sustainable use of local antioxidant-rich flora, providing a clear roadmap for the agronomic utilization of the focal species to support the regional bioeconomy. Full article

Salinity is one of the major problems limiting plant growth, development, survival, yield, and quality. Climate change and increasing salinity levels force a concentration on sustainable production systems. Therefore, this study aimed to determine the effects of different doses of gibberellic acid (GA₃) (0, 150, and 300 mg/L) and salicylic acid (SA) (0, 0.25, and 0.50 mM) priming on some morphological and antioxidant enzyme activities of silage maize (Zea mays L.) seedlings exposed to salinity stress. Four different NaCl (0, 75, 150, and 225 mM) concentrations as salt stress and three different doses of both SA and GA₃ were investigated. The data obtained were subjected to analysis of variance according to a randomized complete block design using a factorial experimental design with four replications per treatment in 3 L pots. The results showed that GA₃ and SA priming had statistically significant effects on all investigated traits under different salt concentrations (except water content). Findings revealed that shoot, root, and leaf development, as well as antioxidant enzymes, were suppressed by salinity stress. The silage maize plant was statistically significantly affected starting from the lowest dose of 75 mM, depending on salt concentrations. Increasing salt concentrations negatively affected above-ground and below-ground parameters. However, SA and GA₃ treatments had positive impacts on all examined traits. SA and GA₃ priming treatments emerged as important strategies supporting root and shoot growth under saline conditions, thereby strengthening plant adaptation. The best results were obtained in groups exposed to 75 mM salt stress, where 300 mg/L GA3 was applied, and in groups without salt stress, where the same GA3 dose was applied. It was concluded that GA₃ priming treatments, in particular, were more effective than SA treatments, alleviating salt stress and positively contributing to plant development. Full article

Plantain (Musa paradisiaca) is a climacteric fruit with high endogenous ethylene production, which accelerates ripening and limits shelf life, especially during transport and exportation, leading to significant losses for producers and distributors. This study evaluated the effect of gibberellic acid (GA₃) and zeatin (Zea) on delaying the ripening of Hartón plantains grown in Colombia. The goal was to assess whether these plant regulators could delay physicochemical changes under simulated cold chain conditions. A completely randomized design was used with nine treatments, plus a control, each with five replicates. Fruits were stored at 11 ± 2 °C and 75% relative humidity for 25 days. Pulp firmness, soluble solids, titratable acidity, pH, starch, chlorophyll, carotenoids, total polyphenols, and polyphenol oxidase activity were assessed. The combination of GA₃ + Zea was effective in preserving firmness, maintaining starch and chlorophyll content, and limiting increases in soluble solids and polyphenol oxidase activity associated with senescence. This delayed ripening did not affect structural integrity or caused oxidative stress. Combined application of GA₃ and Zea is a low-cost and effective strategy to extend the shelf life of plantains for export, benefiting the tropical agri-food chain. This approach offers a practical alternative for maintaining fruit quality without the need for costly preservation technologies. Full article

Origanum petraeum Danin, an endemic medicinal shrub from Jordan, belongs to the Lamiaceae family and possesses significant pharmaceutical potential, yet its secondary metabolite profile remains largely unexplored. This study evaluated the effects of two types of nanoparticles, silver (Ag) and copper (Cu), on in vitro propagation and secondary metabolite composition in O. petraeum microshoots. Sterilized buds were used to initiate in vitro cultures on Murashige and Skoog (MS) medium supplemented with gibberellic acid (GA₃) at 0.5 mg/L. Microshoots were treated with nanoparticles at concentrations of 0, 25, 50, 100, and 150 mg/L. AgNPs at 100 mg/L promoted growth, increasing the number of microshoots to 11.6 and shoot height to 9.22 cm. Transmission electron microscopy confirmed nanoparticle uptake and translocation, with AgNPs observed in root cells as small particles (≤24.63 nm), while CuNPs formed aggregates in leaves (47.71 nm). GC-MS analysis revealed that nanoparticles altered the volatile composition; 50 mg/L CuNPs enhanced monoterpenes, including α-terpinyl acetate (29.23%) and geranyl acetate (12.76%), whereas 50 mg/L AgNPs increased sesquiterpenes, such as caryophyllene oxide (28.45%). Control in vitro cultures without nanoparticles showed simpler profiles dominated by caryophyllene oxide, while wild plants contained both monoterpenes and sesquiterpenes, with eudesm-7(11)-en-4-ol (25.10%) as the major compound. Nutrient analysis indicated that nanoparticles influenced nutrient composition in microshoots. This study is the first to report nanoparticle-assisted growth and essential oil composition in O. petraeum, demonstrating their potential to enhance growth and secondary metabolite production for pharmacological and biotechnological applications. Full article

Sedum alfredii is a cadmium (Cd) hyperaccumulator, but the regulatory mechanisms linking phytohormones and redox balance to Cd transporter expression remain unclear. In this study, we omitted external cadmium (Cd) stress to isolate and examine the interplay between phytohormone and reactive oxygen species (ROS) signaling. Exogenous treatments with abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellic acid (GA₃), trans-zeatin (t-Z), and H₂O₂ were combined with analyses of hormone levels, antioxidant enzyme activities, and transporter gene expression. Correlation and PLS-SEM analyses identified the CAT–H₂O₂ module as a key node: ABA and IAA enhanced CAT activity and alleviated ROS-mediated repression of transporters, while GA₃ and t-Z exerted opposite effects. Functional validation using an H₂O₂ scavenger revealed that the regulation of HMA3 and Nramp5 by ABA and t-Z is H₂O₂-dependent. In contrast, IAA modulates Nramp5 through a ROS-independent pathway, while the regulatory effects of GA₃ were negligible. Functional validation under Cd exposure suggests a model wherein HMA3 and Nramp5 act in a complementary manner to sequester and redistribute Cd in leaves, thereby supporting hyperaccumulation. These findings highlight hormone-specific ROS pathways as central to transporter regulation and provide mechanistic insights to improve phytoremediation efficiency. Full article

The Passifloraceae family is one of the most representative in tropical America, with food, pharmaceutical, and ornamental importance. This study evaluated seed morphometry and germination of eight accessions of four Passiflora edible species, P. edulis; P. ligularis; P. quadrangularis; and P. tripartita var. mollissima, by studying accessions conserved several years in the gene bank (−15 °C) and recently collected accessions. Four experimental phases were carried out as follows: (1) morphometric characterization of seeds with qualitative and quantitative variables; (2) evaluation of germination under two thermal regimes (20 °C/30 °C and 25 °C); (3) application of six pre-germination treatments to overcome dormancy; and (4) tetrazolium tests. In phase 1, P. quadrangularis stood out for its unique morphological characteristics according to multivariate analysis. In phase 2, the alternating thermal regime (20 °C/30 °C) promoted the highest germination. In phase 3, the germination response was specific to each species: mechanical scarification in P. edulis (85.7%), KNO₃ (0.5%) in P. ligularis (35.7%), control in P. quadrangularis (71.1%), and gibberellic acid (GA₃ 400 ppm) in P. tripartita (71.4%). The tetrazolium phase 4 identified the viability status of the seeds. It is concluded that the differences in morphometry and germination reflect the intrinsic characteristics of each species, highlighting the importance of specific protocols for their germination. This study provides tools to optimize the conservation and regeneration of Passiflora spp. germplasm under ex situ conditions, as a genetic base to be utilized in the future. Full article

Species of Trichoderma are currently in high demand as eco-friendly and commercial biocontrol agents due to the proliferation of organic farming methods. This study focused on the potential biocontrol agents of Trichoderma against plant-pathogenic fungi. Trichoderma strains were isolated from different sources (soil, grapevine tissues, lemon fruit, and maize seeds), and were characterized morphologically on two culture media, i.e., Potato Dextrose Agar and Malt Extract Agar, and molecularly using two gene regions: translation elongation factor 1 (TEF) and nuclear ribosomal internal transcribed spacer (ITS). Phylogenetic trees were constructed. As a result, two Trichoderma species were identified, i.e., T. afroharzianum and T. longibrachiatum. The biocontrol effects of all isolated strains of Trichoderma on Fusarium plant damping-off and the promotion of plant growth were evaluated. Additionally, the antagonistic efficiency of Trichoderma spp. against F. proliferatum using the dual-culture method was evaluated. Under greenhouse conditions, T. afroharzianum strains AEMCTa3 and AEMCTa6 were used to treat maize plants infected with Fusarium. The application of Trichoderma significantly reduced the disease index to 15.6% and 0%, respectively. Additionally, maize seedlings showed significant improvements in shoot and root lengths and fresh and dry weights and increased photosynthetic pigment contents compared to Fusarium-infected plants and the untreated control. The gas chromatography–mass spectrometry (GC-MS) analysis of T. afroharzianum extracts identified a variety of bioactive compounds. These compounds included antifungal substances like N-ethyl-1,3-dithioisoindoline, as well as plant growth-promoting hormones like 6-pentyl-α-pyrone and gibberellic acid. Interestingly, the analysis also revealed new phenylacetic acid derivatives that may play important roles in both plant health and disease resistance. From a practical perspective, developing diverse application methods for Trichoderma is essential to optimize its role as a biocontrol agent and a plant growth promoter, thereby supporting sustainable agriculture through improved adaptability and effectiveness across different farming systems. Full article

Plant growth regulators (PGRs) are widely used to enhance table grape quality, yet cultivar-specific responses and microstructural outcomes remain insufficiently resolved. We evaluated five PGRs—gibberellic acid (GA₃), 24-epibrassinolide (EBR), forchlorfenuron (CPPU), thidiazuron (TDZ), and streptomycin (SM)—in ‘Shine Muscat’ and ‘Red Muscat of Alexandria’. Twelve combinations were applied at full bloom (D0) and 14 days post-anthesis (D14), and morphological, physiological, and histological traits were monitored over 104 days. In ‘Shine Muscat’, GA₃ + TDZ and GA₃ + CPPU achieved nearly 100% seedlessness, while CPPU and TDZ markedly increased berry weight and size via cortical expansion. GA₃ increased berry weight but caused rachis thickening and reduced total soluble solids (TSS). EBR at concentrations ≥ 0.2 mg L⁻¹ inhibited berry growth, and SM reduced berry size and weight. Histology showed that TDZ and CPPU enlarged cortical area and epidermal thickness, potentially strengthening pericarp robustness, whereas GA₃ enlarged vascular bundle area. ‘Red Muscat of Alexandria’ showed generally weaker responses, reflecting differences between Vitis vinifera and hybrid backgrounds. These results demonstrate that combinatorial PGR strategies can be tailored to optimize berry development and quality through coordinated regulation of growth, metabolism, and microstructure. TDZ and CPPU exhibit strong production potential for enlargement, whereas GA₃ and EBR require careful dose optimization to balance benefits and quality risks. Full article

We investigated the effect of Agrobacterium rhizogenes-mediated transformation mof rolB on adventitious root development and endogenous hormones in ‘duli’ (Pyrus betulaefolia) via transcriptomic analysis of wild-type (WT) and rolB-transformed plants. The formation of root primordia occurred earlier in transgenic ‘duli’ than in the WT plants. At seven days, 57% of the transgenic seedlings had formed root primordia, whereas root primordia first appeared at seven days in WT ‘duli’. The rooting rate of transgenic ‘duli’ and WT plants was 90% and 77.14%, respectively. rolB significantly promoted the formation of secondary roots. Within 20 days, auxin (IAA), gibberellic acid (GA₃), and zeatin riboside (ZR) were higher and abscisic acid (ABA) was lower in transgenic ‘duli’ than in WT plants. Gene Ontology analysis revealed high enrichment in signaling pathways and ADP binding, and Kyoto Encyclopedia of Genes and Genomes pathway analysis indicated that several differentially expressed genes were enriched in flavonoid and carotenoid-related pathways and plant hormone signal transduction. rolB induced changes in the expression patterns of several genes involved in hormone biosynthesis, metabolism, and signal transduction pathways in ‘duli’. Weighted gene co-expression network analysis identified the DEGs associated with endogenous hormone levels and indicated that the central genes of modules most strongly correlated with ABA, ZR, IAA, and GA₃ regulate protein synthesis, signaling, and root tissue meristem activity. Protein–protein interaction analysis yielded a co-expression network of physiological and transcriptomic data during rooting and identified key genes at the network core. These findings provide valuable insights into the regulatory mechanisms of rolB and its influence on root development in ‘duli’. Full article

Sugar beet is one of China’s major cash crops, and Inner Mongolia has become an important sugar base in China. However, cultivation of sugar beet in Inner Mongolia could be improved, as it contains 1.06 million hectares of saline–alkali land, accounting for 11.4% of the total arable land in the region. This saline–alkali land challenges the potential for sugar-beet cultivation as excessive concentrations of saline and alkaline substances, in addition to ionic components, have been demonstrated to have a detrimental effect on the growth of crops, including sugar beet. In sugar beet, excessive concentrations of saline and alkaline substances impact the normal metabolism of sugar beets, thereby inhibiting their growth and development. The present study posits that the utilization of a microbial fertilizer has the potential to mitigate the repercussions of saline–alkali stress. The application of microbial fertilizer has been demonstrated to exert a substantial influence on the accumulation of soluble sugars, soluble proteins and free proline in sugar beet roots and leaves. This study demonstrated a decrease in malondialdehyde (MDA) content and an increase in the K⁺/Na⁺ ratio following treatment with a microbial fertilizer. Furthermore, increased activity of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) enzymes was observed. These changes induced an increase in the contents of indole-3-acetic acid (IAA), gibberellic acid (GA) and zeatin (ZR) and a decrease in abscisic acid (ABA) content. The results also indicate an increase in the seedling retention rate and fresh weight of sugar beets. Full article