赤霉素在水杨酸诱导采后番茄果实抗冷中的作用机制研究

Chilling injury is the main restrictive factor for the storage of cold sensitive fruits and vegetables, research on cold-resistant mechanism and developing safe, effective and economic cold-resistant inducing methods have important theoretical and practical significance. Researches show that salicylic acid (SA) as a signal molecule plays a crucial role in fruit anti-cold process. Gibberellins (GA) are important endogenous phytohormones that participate in the responses of plants to biotic and abiotic stress. The existence of a cross talk between SA and GA has been recently verified. We will use postharvest tomato fruits of wild type and GA-deficient mutant gib-3 as materials, to explain the role of ent-kaurene synthase (KS)-mediated GA biosynthesis in SA-induced cold resistance in fruits at molecular, cellular and biochemical level. Screening key regulatory factors by transcriptomic methods can help finding key regulators between SA and GA signaling pathway, revealing possible mechanism of synergism between SA and GA in cold resistance inducement of postharvest fruits and exploring new fruit cold-resistant induction methods.

冷害是冷敏型果蔬低温贮藏的主要制约因素，探索果蔬抗冷机制，开发安全、高效、经济的抗冷诱导方法具有重要的理论和实践意义。研究表明，水杨酸（SA）作为信号分子在果实抗冷诱导过程中发挥重要作用。赤霉素（GA）是一类重要的植物内源激素，参与植物对生物及非生物胁迫的响应，且与SA存在互作关系。本研究拟采用野生型和GA缺失型突变株gib-3的采后番茄果实为材料，从分子水平、细胞水平、生化水平等多个层面系统地研究贝壳杉烯合酶（KS）调控的GA合成途径在SA诱导果实抗冷过程中的作用地位，利用转录组学高通量测序技术筛选SA和GA诱导果实抗冷过程中的共性差异表达基因，确定两信号途径的关键调控点，深入探讨SA和GA调控采后果实抗冷的协同作用机制，为探索果实综合抗冷调控机制及开发抗冷诱导新方法提供理论依据。

冷害是冷敏型果蔬低温贮藏的主要制约因素，探索果蔬抗冷机制，开发安全、高效、经济的抗冷诱导方法具有重要的理论和实践意义。本项目（1）首先研究低温对采后番茄果实的赤霉素（GA）动态平衡的影响，确定GA及其信号途径参与番茄果实的抗冷过程；（2）明确了外源赤霉酸（GA3）处理可提高番茄果实抗冷性，且该过程可能与激活水杨酸（SA）信号和CBF途径相关；（3）阐明了SA诱导的番茄果实抗冷过程与GA动态平衡、CBF途径及抗氧化酶系统相关；（4）以野生型和GA缺失型突变株gib-3的采后番茄果实为材料，发现GA合成受阻降低番茄果实的抗冷性；（5）基于组学手段研究GA调控番茄果实抗冷的分子机制，分析GA调控番茄果实抗冷过程中的差异表达基因和蛋白，确定GA调控番茄果实抗冷的关键控制点。本项目为探索果实综合抗冷调控机制及开发抗冷诱导新方法提供理论依据。