Search Results (2,337)

The yield and quality have long been constraining factors for the sustainable cultivation of Glycyrrhiza uralensis. This study evaluated the effects of foliar applications of forchlorfenuron (CPPU) at different concentrations (0, 5, 10, 20, and 40 mg·L⁻¹) on plant growth and secondary metabolism through comprehensive analyses of photosynthesis, endogenous phytohormones, root biomass, and medicinal components. To ensure consumer safety, CPPU residue dynamics and associated health risks were also assessed. The 10 mg·L⁻¹ treatment yielded the most pronounced improvements, increasing root biomass by 46%, glycyrrhizic acid content by 92%, and liquiritin content by 98.7%. It also enhanced the activity of ribulose-1,5-bisphosphate carboxylase, thereby improving overall photosynthetic gas exchange capacity, and significantly stimulated the synthesis of zeatin, abscisic acid, and salicylic acid. Residue analysis showed that by the 56th day after treatment, the CPPU level in roots was merely 5.44 × 10⁻⁴ mg·kg⁻¹, with a half-life of 11.74 days. The resulting risk quotient (RQ) was below 0.01%, well under the safety threshold of 1, indicating negligible health risk to consumers. Our results demonstrate that the targeted application of CPPU offers a highly effective and safe strategy for enhancing both the productivity and commercial quality of G. uralensis. Full article

Mitogen-Activated Protein Kinases (MAPKs) play crucial roles in plant stress signaling, but the mechanisms of MAPK genes in Portulaca oleracea remain functionally uncharacterized. In this study, transcriptomic screening of P. oleracea under salt stress identified PoMPK3 as a candidate gene, showing significant root-specific upregulation. Phylogenetic analysis classified it as a Group A MAPK protein, and subcellular localization confirmed its membrane association. Heterologous expression of PoMPK3 in Arabidopsis thaliana significantly enhanced salt tolerance, as evidenced by improved seed germination rates, longer primary roots, increased biomass, and reduced stress symptoms. Mechanistically, PoMPK3 expression activated ABA signaling, leading to increased ABA levels and upregulation of AtNCED3, AtPYR1, and AtABF3. Furthermore, it strengthened the antioxidant defense, as evidenced by elevated antioxidant enzyme activity, leading to a reduction in oxidative stress. The transgenic lines also demonstrated enhanced osmotic adjustment through osmolytes accumulation and ionic homeostasis, evidenced by tissue-specific Na⁺/K⁺ ratios (low in shoots, high in roots) resulting from the concerted upregulation of AtSOS1, AtNHX1, and AtHKT1. In addition, gene co-expression network analysis and molecular docking predicted phosphorylation of WRKY transcription factors, suggesting a novel mechanism for transcriptome reprogramming. Collectively, our findings not only advance the understanding of salt tolerance mechanisms in purslane but also identify PoMPK3 as a key genetic determinant, thereby laying the foundation for its use in breeding programs aimed at enhancing salt stress resilience in crops. Full article

Northern corn leaf blight (NCLB), caused by Exserohilum turcicum, is a major foliar disease of maize worldwide. To develop sustainable alternatives that reduce chemical products, we evaluated Bacillus velezensis EM-A8 (GenBank accession number OL704805) as a biocontrol agent under greenhouse and field conditions. The aims of this study were as follows: (i) characterize phytohormone production in two formulations containing the BCA; (ii) assess the influence of the BCA on plant biomass and yield; (iii) compare the efficacy of both formulations in controlling NCLB under field conditions; and (iv) determine whether the treatments affected salicylic acid and phenolic compound levels in maize tissues. The strain synthesized a broad spectrum of phytohormones, including salicylic acid, indoleacetic acid, indolebutyric acid, jasmonic acid, abscisic acid and gibberellic acid, as well as cytokinins such as kinetin, zeatin, and 6-benzylaminopurine. Foliar application increased maize dry biomass by 30%. In field trials, both formulations effectively suppressed NCLB, reducing the number of symptomatic leaves by 25–50% compared with controls. Furthermore, treated plants exhibited yield increases exceeding 1000 kg/ha. These findings demonstrate that B. velezensis EM-A8 provides effective biocontrol of E. turcicum while simultaneously enhancing maize growth and yield under field conditions. Future work should aim to scale up the use of B. velezensis EM-A8 in integrated pest management programs and evaluate its long-term impact on soil microbiota, plant health, and yield sustainability. Full article

Northern corn leaf blight (NCLB), caused by the fungal pathogen Setosphaeria turcica, is a devastating foliar disease that significantly threatens maize production in China. Previous studies have demonstrated that SET domain gene 102 (SDG 102), a gene encoding an H3K36 methyltransferase, plays a crucial role in regulating maize growth, development, and stress responses. This study used the wild-type (WT), SDG102 overexpression line (OE), and silencing line (SL) of the corn inbred line B73 as materials. After artificial inoculation with S. turcica, the phenotypic characteristics, disease index, yield, and other related traits of different strains were compared, and RNA-Seq was used to analyze the changes in the gene expression profile. The results showed that overexpression of SDG102 significantly inhibited pathogen spore germination and hyphal growth and enhanced the activity of antioxidant enzymes and the ability to scavenge reactive oxygen species in plants prior to S. turcica infection, the opposite trend was observed in SDG102 silencing lines. Compared with the wild-type, 1546 and 1837 differentially expressed genes (DEGs) responsive to S. turcica were identified in OE and SL, respectively. These differentially expressed genes primarily function in pathways such as plant–pathogen interactions, plant hormone signaling, and secondary metabolite biosynthesis. In the OE lines, genes related to plant–pathogen interactions, reactive oxygen species (ROS) production, and key phenylpropanoid biosynthesis genes exhibited higher expression levels. Furthermore, SDG102 regulates the synthesis of auxin (JA) and abscisic acid (SA) as well as the transcription of their signaling pathway genes, thereby influencing maize resistance to large leaf spot disease. Under corn leaf blight conditions, SDG102 overexpression increased yield by 9.29% compared to WT, while SL reduced yield by 10.10%. In conclusion, SDG102 enhances maize resistance to NCLB by positively regulating the expression of disease resistance genes, antioxidant enzyme activity, and hormone-mediated defense pathways. Full article

Understanding the molecular crosstalk between drought and iron (Fe) homeostasis is crucial for developing drought-tolerant wheat cultivars with enhanced nutrient quality. In this study, transcriptomic data mining identified 23,271 and 5933 differentially expressed genes (DEGs) under drought and Fe deficiency, respectively, with 2479 DEGs in response to both stresses. Notably, this overlapping set included significant numbers of genes encoding transcription factors (TFs) (149 genes), Fe homeostasis components (274 genes), and those involved in phytohormones pathways (245 genes), particularly the abscisic acid (ABA) pathway. Gene Ontology (GO) analysis revealed specific and commonly affected biological processes, such as response to abiotic stimulus and heme binding. Furthermore, co-expression network analysis revealed modules highly enriched with genes involved in transcriptional regulation and Fe uptake, enabling the identification of key hub regulatory genes, belonging to the MYB, NAC, BHLH, and AP2/ERF families, involved in the shared stress response. Finaly, the expression of a set of candidate TF-encoding genes was validated using qRT-PCR in durum wheat under drought and Fe starvation, providing a detailed overview of the possible shared regulatory mechanisms linking drought and Fe deficiency responses. Full article

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

The objective of this work was to assess the association of ACC (1-aminocyclopropane-1-carboxylic acid), S-ABA (abscisic acid), and ethephon on color development and anthocyanin accumulation in berries, as well as on other quality attributes of ‘Benitaka’ and ‘Rubi’ table grapes grown in a subtropical region, in addition to postharvest conservation of clusters and vine regrowth. As a statistical model, a randomized block design consisting of nine treatments and four replications was used. The treatments included different associations of ACC, S-ABA, and ethephon, by using the commercial formulations Accede^®, ProTone^®, and Ethrel^® containing 400 g kg⁻¹ of ACC, 100 g L⁻¹ of S-ABA, and 720 g L⁻¹ of ethephon, respectively. The total anthocyanins, berry color index (CIRG), physicochemical characteristics, and cluster color coverage were assessed weekly, while berry firmness was assessed at harvest. After being harvested, the clusters were placed under cold storage at 1.0 ± 1.0 °C, and after 45 days, their postharvest attributes were assessed, as well as the vine regrowth in the following season. The exogenous and combined application of compounds at véraison was demonstrated to be a strategy to trigger the development of color in ‘Benitaka’ and ‘Rubi’ table grapes. For the ‘Benitaka’ table grape, the clusters treated with the different combinations of ACC and S-ABA, ethephon and S-ABA, or ethephon alone resulted in the highest concentration of total anthocyanins and the highest CIRG means (4.90; 4.86; 4.82; 4.81, 4.73, and 4.70 mg g⁻¹ for anthocyanins, and 6.12, 6.08, 5.97, 5.92, 5.85, and 5.74 for CIRG, respectively). For the ‘Rubi’ table grape, the combinations of ACC and S-ABA at 7 days after véraison (DAV), or ethephon and S-ABA at 7 and 14 days, resulted in higher means of anthocyanins and CIRG (3.86, 3.51, and 3.40 mg g⁻¹ for anthocyanins and 5.05, 4.68, 4.82, and 4.79 for CIRG, respectively). Furthermore, the firmness of the berries of both cultivars remained unchanged, and after 45 days of cold storage, no reduction in the quality of the evaluated postharvest attributes was found. It was concluded that a single application of ACC 0.20 g L⁻¹ + S-ABA 0.250 g L⁻¹ at 7 DAV was sufficient to promote the accumulation of anthocyanins and resulted in an intense and uniform color in the berries for both varieties assessed, with no adverse impacts on the postharvest conservation of the clusters or on the regrowth of the vines. The significance of this research was to demonstrate that table grapes with insufficient skin color can be improved through a combination of S-ABA and ACC at lower concentrations of active ingredients. Full article

Soil salinization significantly limits plant growth and agricultural productivity, with MYB transcription factors playing crucial roles in mediating plant responses to salt stress. In this study, a novel R2R3-MYB transcription factor gene, SlMYB306-like, was isolated from tomato. Phylogenetic comparison indicated that SlMYB306-like shared the highest sequence homology with potato StMYB306-like. Subcellular localization assays demonstrated nuclear localization of SlMYB306-like protein, while yeast transactivation assays confirmed its function as a transcriptional activator. Expression profiling showed that SlMYB306-like was inducible by NaCl and abscisic acid (ABA) treatments. In addition, functional characterization via the overexpression of SlMYB306-like in Arabidopsis thaliana revealed enhanced salt tolerance, evidenced by an increased maximum quantum efficiency of photosystem II (Fv/Fm) and proline levels alongside decreased accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA) content under salt stress conditions. Furthermore, the overexpression of SlMYB306-like upregulated the expression of several stress-responsive genes, including AtSOD1, AtCAT1, AtEGY3, AtP5CS2, and AtRD29A. Collectively, these findings suggest that SlMYB306-like enhances salt tolerance by modulating ROS scavenging, osmotic adjustment, and ABA signaling pathways, thereby representing a promising candidate gene for the development of salt-tolerant crops. Full article

Litchi is an important subtropical fruit, highly valued by consumers for its vibrant color and distinctive flavor. B-box (BBX) proteins, which are zinc finger transcription factors, play a crucial role in regulating plant growth, development, and stress responses. Nevertheless, the specific function of BBX genes in the development and coloration of litchi fruit remains inadequately understood. In this study, 21 LcBBX genes (designated as LcBBX1-LcBBX21) were identified within the litchi genome. These genes were categorized into five sub-families based on phylogenetic analysis and were found to be unevenly distributed across 12 chromosomes. Promoter analysis revealed a rich presence of light-responsive elements, such as the G-box, and abscisic acid (ABA) responsive elements, including ABRE, within the promoter regions of LcBBX genes. Protein–protein interaction predictions indicated that the majority of LcBBX genes have the potential to interact with the light-responsive factor HY5. Transcriptome analysis and qRT-PCR results demonstrated that LcBBX genes exhibit tissue-specific expression patterns. Notably, most LcBBX genes were highly expressed prior to fruit coloration, whereas LcBBX4 and LcBBX10 were upregulated during the fruit coloration phase. Furthermore, LcBBX1/4/6/7/15/19 were upregulated in response to light following the removal of shading. The findings suggest that LcBBX4 may directly regulate anthocyanin biosynthesis in litchi pericarp. This study provides critical insights into the molecular mechanisms underlying litchi fruit development and coloration. Full article

Salt stress is a major form of abiotic stress that disrupts soybean germination and early seedling establishment. In this study, physiological, biochemical, and transcriptomic analyses—including germination index, antioxidant enzyme activity, and RNA-seq profiling—were conducted during soybean germination to elucidate early responses to salt stress and biostimulant treatment. A preliminary screening of six biostimulants (nanoparticle zinc oxide (NP-ZnO), nanoparticle silicon dioxide (NP-SiO₂), silicon dioxide (SiO₂), glucose, humic acid, and fulvic acid) revealed NP-SiO₂ as the most effective in promoting germination under salt stress. Under 150 mM NaCl, NP-SiO₂ increased the germination rate and length of the radicle compared with the control, also enhancing peroxidase and ascorbate peroxidase activities while reducing malondialdehyde accumulation, suggesting alleviation of oxidative stress. RNA sequencing revealed extensive transcriptional reprogramming under salt stress, identifying 4579 differentially expressed genes (DEGs) compared with non-stress conditions, while NP-SiO₂ treatment reduced this number to 2734, indicating that NP-SiO₂ mitigated the transcriptional disturbance caused by salt stress and stabilized gene expression networks. Cluster analysis showed that growth- and hormone-related genes suppressed by salt stress were restored under NP-SiO₂ treatment, whereas stress-responsive genes that were induced by salt were attenuated. Hormone-related DEG analysis revealed that NP-SiO₂ down-regulated the overactivation in the abscisic acid, jasmonic acid, and salicylic acid pathways while partially restoring gibberellin, auxin, cytokinin, and brassinosteroid signaling. Overall, NP-SiO₂ at 100 mg/L mitigated salt-induced oxidative stress and promoted early soybean growth by fine-tuning physiological and transcriptional responses, representing a promising nano-based biostimulant for enhancing salt tolerance in plants. Full article

Agave species possess substantial cultural, ecological, and economic significance, particularly in Mexico, where they are traditionally utilized for food, fiber, and beverages. Their industrial relevance has expanded to include bioenergy, nutraceuticals, and sustainable agriculture. However, conventional propagation methods are constrained by long life cycles, low seed germination rates, and susceptibility to phytopathogens. In vitro culture has emerged as a pivotal biotechnological strategy for clonal propagation, germplasm conservation, and physiological enhancement. This review presents a critical synthesis of plant growth regulators (PGRs) employed in agave micropropagation, emphasizing their roles in organogenesis, somatic embryogenesis, shoot proliferation, and rooting. Classical PGRs such as 6-benzylaminopurine (BAP), benzyladenine (BA), 2,4-dichlorophenoxyacetic acid (2,4-D), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA) are widely utilized, with BA + 2,4-D and BA + IAA combinations demonstrating high efficiency in embryogenic callus induction and shoot multiplication. Additionally, non-traditional regulators such as abscisic acid (ABA) and putrescine (Put) have been shown to affect embryo maturation. This review synthesizes recent studies on agave in vitro culture protocols, identifies trends in PGR use, and highlights key research gaps. These insights reveal opportunities for innovation and underscore the need for species-specific optimization and molecular validation to improve reproducibility and scalability. Full article

Triterpenoid saponins are important secondary metabolites in plants. Abscisic acid (ABA), as one of the indispensable regulatory hormones in plants, promotes the accumulation of bioactive components in various plants, including triterpenoid saponins; however, its induced mechanism in Hedera helix remains unclear. In this study, the treatment of H. helix leaves with 100 μM ABA led to the identification of 7108 differentially expressed genes (DEGs) within 6 h post-treatment through transcriptomic and bioinformatic analysis. Enrichment analyses of GO terms and KEGG pathways indicated significant enrichment of DEGs in terpenoid backbone biosynthesis pathways. Analysis of DEGs revealed the NAC transcription factor, which is crucial for plant growth regulation, stress response, and secondary metabolite biosynthesis. A total of 182 HhNACs were identified at the genome-wide level, named HhNAC1 to HhNAC182 according to their chromosomal positions. Numerous ABA-responsive cis-regulatory elements (CREs) were presented at upstream promoters of HhNAC1 to HhNAC182. They demonstrated diversified tissue-specific expression profiling among stems, roots, and leaves of H. helix. Notably, HhNAC93 was predominantly expressed in H. helix leaves. Correlation analysis unveiled a markedly positive relationship among ABA-induced HhNAC93 expression, triterpenoid saponin accumulation, and the expression of essential saponin biosynthetic genes. HhNAC93 likely functions as a candidate regulator in triterpenoid saponin biosynthesis. These findings provide crucial evidence for further exploring the biological role of HhNAC transcription factor in H. helix. 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

Improving plant water use efficiency (WUE) and drought tolerance by modulating stomatal activity constitutes a promising strategy for mitigating the impacts of water scarcity. SnRK2, a key component of the abscisic acid (ABA) signaling pathway, plays a critical role in modulating stomatal behavior under abiotic stress. However, the functional role of SnRK2 in regulating stomatal movement to enhance WUE and drought tolerance in Populus euphratica remains to be characterized. In this study, 11 PeSnRK2 genes were identified in the P. euphratica genome, each comprising 9–14 exons and exhibiting an uneven distribution across seven chromosomes. Subcellular localization predictions indicated that these proteins are predominantly localized in the Cytoplasm and Cytoskeleton. Phylogenetic analysis grouped the PeSnRK2 genes into three distinct subfamilies, and conserved gene structures were observed within each clade. Analysis of cis-acting regulatory elements suggested that PeSnRK2 genes were involved in hormonal signaling and stress response pathways. Further transcriptomic data also indicated substantial alterations in PeSnRK2 expression due to polyethylene glycol (PEG) and abscisic acid (ABA) treatment. Finally, qRT-PCR and subcellular localization showed that PeSnRK2.6 is highly induced by ABA and functions in both nucleus and cytoplasm. This first characterization in a desert woody species bridged gaps in SnRK2 evolution and function. Full article

Different pollination methods can affect the development and quality of watermelon fruit. The physiological changes in the early development of watermelon after using different pollination methods are unclear. In this study, we focused on the effects of hand pollination (H), honeybee pollination (HB), and bumblebee pollination (BB) at 1 day after pollination (1DAP) on the fruit setting rate, size, and endogenous hormone, gene, and protein expression levels using the transcriptome and proteome in greenhouse watermelon. Thus, we studied the physiological indicators of the final fruit at 40 DAP. At 1 DAP, the fruit setting rate and size of watermelon embryos showed no significant differences between the three groups. The indole-3-acetic acid (IAA) and isopentenyl adenosine (iPA) contents in the H group were highest, followed by the BB group and HB group. The abscisic acid (ABA) and gibberellin (GA3) contents were significantly higher in the BB group than in the H and HB groups. The zeatin (ZT) and carotenoid contents were lowest in the H group. The DEGs in H vs. HB and H vs. BB were mainly involved in plant hormone signal transduction, as well as amino acid and lipid metabolism. Moreover, phenylpropanoid biosynthesis and carotenoid biosynthesis were involved in H vs. HB, and carbohydrate metabolism was involved in H vs. BB. The DEGs in HB vs. BB were mainly involved in pathways including zeatin biosynthesis and photosynthesis. The DEPs in H vs. HB and HB vs. BB were involved in flavonoid biosynthesis, whereas the DEPs in H vs. BB were involved in ribosomes and oxidative phosphorylation. At 40 DAP, bee pollination can promote sugar content and transportation. Functional and pathway changes among key genes and proteins and pheromones may co-regulate plant development. This study provides data support for exploring the effects of pollination techniques on watermelon fruit development under greenhouse conditions. Full article