Plant Science最新文献

Drought threatens apple (Malus domestica) growth and productivity, often leading to irreversible economic losses. C1-papain family cysteine proteases are key enzymes in plant responses to abiotic stress, yet their specific roles under drought conditions remain largely uncharacterized in apple. Sequence analysis identified MdCP37 as a member of the C1-papain family. Here, we demonstrate that overexpression of MdCP37 (OE) in transgenic apple increases drought sensitivity, while RNAi-mediated silencing of MdCP37 enhances drought tolerance. Under drought stress, MdCP37-OE lines displayed reduced antioxidant enzyme activity and suppressed expression of drought-responsive genes, whereas RNAi lines exhibited opposite trends. Moreover, MdCP37 accelerated chlorophyll and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) degradation and promoted leaf senescence under drought conditions. Collectively, our findings establish MdCP37 as a negative regulator of drought tolerance in apple and offer theoretical support for improving drought resilience in apple breeding programs, particularly in arid regions.

Allelopathy has been viewed as an interaction in which plant-released secondary metabolites suppress the growth of neighboring plants through direct toxic effects. However, this perspective likely overestimates the role of toxicity. It remains unresolved whether the inhibitory effects commonly attributed to allelopathy primarily reflect passive physiological damage in recipient plants or instead arise from actively regulated responses initiated by the recipients themselves. Here, we establish an integrative framework to re-evaluate allelopathic effects, using Chrysanthemum seticuspe as an ecologically representative recipient species. Rather than treating allelopathy as an intrinsic property of a single donor plant, we adopt a recipient-centered perspective and systematically examine responses across developmental, cellular, physiological, hormonal, and transcriptomic scales, with interactions involving Triadica sebifera (Euphorbiaceae) leaf litter powder serving as an illustrative case. Growth assays revealed persistent suppression of early radicle elongation in recipient plants. Notably, this suppression was not associated with widespread cellular structural disruption. Instead, recipient plants exhibited predominantly coordinated regulatory responses, including transient oxidative signaling, activation of detoxification pathways, extensive hormonal reprogramming, and downregulation of growth-associated metabolic processes. Together, these responses indicate a regulated shift toward defense-prioritized developmental states rather than irreversible toxic injury. Collectively, our findings support a reinterpretation of allelopathy as a process that operates primarily through allelochemical interference, inducing active regulatory reprogramming in recipient plants. Under natural, low-concentration conditions, such interactions are likely to function as chemo-ecological filters that modulate plant development, tolerance, and competitive outcomes, thereby shaping plant coexistence and community.

Mango is a highly perishable fruit, which limits its marketability and consumer acceptance. Major issues impacting its storability include rapid softening, decline in nutritional quality and susceptibility to decay during postharvest storage. Therefore, this study aimed to examine the influence of postharvest application of melatonin at (0.1, 0.5 and 1mM) on the quality and shelf life of mango cv. Zardalu stored under ambient conditions (temperature: 30±2ºC; RH: 80±5%). A post-harvest melatonin application was found to significantly reduce weight loss and decay while preserving fruit firmness, fruit quality attributes, and shelf life. Moreover, the molecular analysis of genes related to fruit softening i.e., MiPG, MiPME, and MiExpA1, revealed a significant down-regulation of gene expression with melatonin treatment. Melatonin application, particularly at 0.5mM, effectively delays postharvest deterioration by modulating fruit softening at both physiological and molecular levels. Our findings highlight the potential of melatonin as an eco-friendly postharvest strategy to enhance shelf life, maintain fruit quality, and improve the marketability of mango under ambient conditions.

Plant height (PH) and main stem node number (MSN) are core agronomic traits that jointly shape soybean plant architecture and determine yield potential. Here, a natural population of 264 soybean (Glycine max (L.) Merr.) accessions was phenotyped for PH and MSN across two environments to dissect their genetic basis. Genome-wide association study (GWAS) revealed that both traits are quantitatively inherited with extensive phenotypic variation, identifying 73 significant single-nucleotide polymorphisms (SNPs) associated with PH (distributed on chromosomes 2, 6, 7, 9, 14, 16, and 19) and 572 SNPs associated with MSN. Notably, loci on chromosomes 6 and 19 were consistently detected across environments, exhibiting stable genetic effects on PH. Candidate gene analysis within the major locus on chromosome 6 identified six potential regulators, among which GmCESA7 (Glyma.06G225500) - encoding a cellulose synthase involved in secondary cell wall biosynthesis - was prioritized. Functional validation using ethyl methyl sulfonate (EMS)-induced gmcesa7 mutants showed that mutants in GmCESA7 were associated with significantly reduced PH at both vegetative and mature stages, supporting a positive role for GmCESA7 in stem elongation. Additionally, the major locus on chromosome 19, which was also associated with MSN via 60 co-localized SNPs across environments, harbored the known plant architecture regulator GmDt1. Collectively, these findings uncover GmCESA7 as a key genetic determinant of soybean PH and highlight conserved genetic pathways regulating PH and MSN, providing valuable genetic resources and a theoretical basis for optimizing plant architecture in soybean breeding.

Lilies are among the most economically important ornamental flowers worldwide, yet their large-scale cultivation is often hindered by limited tolerance to salinity and drought. Lilium pumilum, a wild lily species native to northern China, exhibits remarkable resilience to salinity, drought, and cold, making it a valuable genetic resource for stress tolerance studies. In this study, the transcription factor LpNAC14 was identified through transcriptome sequencing analysis and cloned from L. pumilum. LpNAC14 exhibited differential transcriptional profiles across root, bulb, and foliar tissues of L. pumilum when subjected to abscisic acid (ABA) induction and various abiotic stress conditions, encompassing salinity (NaCl), alkaline stress (NaHCO₃), and water deficit. Under drought and salt stress regimes, transgenic Nicotiana tabacum lines with LpNAC14 overexpression demonstrated markedly enhanced enzymatic activity of key antioxidant systems-specifically peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), as well as increased chlorophyll content, compared to the control group. In contrast, the transgenic lines showed significantly diminished malondialdehyde (MDA) and relative electrolyte leakage (REL) accumulation. Furthermore, the expression levels of stress-responsive genes were significantly upregulated in LpNAC14-overexpressing tobacco, indicating that LpNAC14 enhances tolerance to salt and drought stress. Interestingly, LpNAC14-transgenic tobacco also displayed phenotypic alterations, including reduced plant height and darker flower pigmentation relative to WT. Gene expression analysis demonstrated that anthocyanin biosynthesis genes (NtDFR, NtANS, NtUFGT) were significantly upregulated, whereas anthocyanin-reducing genes (NtLAR, NtANR) were downregulated. These findings suggest that LpNAC14 may promote anthocyanin synthesis by interacting with these genes, thereby contributing to enhanced stress tolerance. This study provides basic understanding of the molecular mechanisms of abiotic stress tolerance and anthocyanin biosynthesis mediated by NAC family transcription factors in Lilium spp. Additionally, LpNAC14 emerges as a promising candidate gene for the genetic improvement of lilies, offering significant potential for the development of stress-resistant cultivars and for advancing horticultural breeding programs.