光周期对梨叶片激素含量及基因表达的影响

Effect of Photoperiod on Hormone Content and Gene Expression in Pear Leaves

光周期是指一天中昼夜的相对长度,广泛调控植物生长发育的多个方面。研究不同光周期条件下梨叶片内源激素的昼夜变化规律,探索内源激素响应光周期诱导的分子机制,能够为协同利用光周期和激素调控植物生长发育提供理论依据。本研究以长日照和短日照条件下生长的梨植株为研究材料,在一天中不同时间点取样,分析了梨叶片中生长素、细胞分裂素、脱落酸、乙烯、茉莉酸等5种内源植物激素含量及相关基因的表达差异。结果表明,梨叶片中5种激素呈现出不同的昼夜动态变化模式;不同光周期条件下激素的含量有显著变化。通过对转录组差异表达基因富集分析发现,多个激素相关的生物过程被显著富集,其中上调的差异表达基因主要富集在生长素运输等过程。对5种激素生物合成代谢、运输和信号转导相关的差异基因表达模式进行分析,筛选到响应光周期诱导的候选关键基因。这些结果为深入探究光周期调控梨激素响应机制提供参考。

Photoperiod refers to the relative length of day and night in a day,widely regulating many aspects of plant growth and development.Studying the diurnal variation of endogenous hormones in pear leaves under different photoperiod conditions and exploring the molecular mechanism of endogenous hormones in response to photoperiod induction can provide theoretical basis for synergistic use of photoperiod and hormones to regulate plant growth and development.In this study,pear seedlings growing under long-day and short-day conditions were sampled at different time points throughout the day.The contents of five endogenous plant hormones,such as auxin,cytokinin,abscisic acid,ethylene and jasmonic acid,and the expression patterns of related genes in pear leaves were analyzed.It was shown that the five hormones in pear leaves showed different diurnal dynamic patterns.The content of hormone changed significantly under two photoperiod conditions.Through the GO analysis of differentially expressed genes in the transcriptome,several hormone-related biological processes were significantly enriched.For example,upregulated differentially expressed genes were mainly enriched in auxin transport processes.Differential gene expression patterns related to hormone biosynthesis,transport and signal transduction were analyzed,and candidate key genes responding to photoperiodic induction were screened.These results provide a reference for further investigation of photoperiod regulation of pear hormone response.