哈密瓜果实磷脂酶D对低温胁迫响应及在冷害中的作用研究

Xinjiang hami melon resource is rich, good quality, is one of the main fruit in xinjiang area. Hami melon cooked aging rapidly, after decay losses can be rather serious. Low temperature cold storage can effectively inhibit fruit postharvest decay. However, hami melon is liable to happen chilling injury at low temperature, cause the sink in the epidermis, gradually develop into the irregular plaques, eventually lead to rot. The plant cell membrane and the main composition of phospholipids are not only a kind of cell structure, but also cells in the initial response to the external environment stress first place, phospholipase D(PLD) is an important transmembrane signal transduction enzyme in cells, plays an important role in signal transduction at low temperature. Hami melon as test materials in this project, OA as a condition treatment to reduce chilling injury, cell membrane phospholipids metabolism by PLD regulation will beresearched mainly, including：PLD activity , the changes and the patterns of their coding genes and protein expressions in the low temperature stress and distributions in the subcellula in different chilling injury time; Determination the quantitative change rule of the cell membrane phospholipids and its decomposition product and the secondary metabolites ; Analysis of the relation with other facters related to chilling injury; The influence of PLD inhibitors of phospholipid metabolism . Explore PLD pattern for the induction under the low temperature stress and effect . The objective to carry out not only help to enrich and develop theoretical system of postharvest physiology, but also provide important theoretical guidance for the development and improvement fresh-keeping technology of fruit and vegetable.

新疆哈密瓜资源丰富，品质优良，是新疆地区的主要水果之一。哈密瓜后熟衰老迅速，腐烂损失相当严重。低温冷藏能有效抑制果实采后腐烂。但哈密瓜属于冷敏性水果，低温冷藏易发生冷害，导致表皮组织下陷成不规则的斑块，最终导致腐烂。植物细胞膜及主要成分磷脂不只是一种细胞结构，也是细胞对外界环境胁迫作出初始响应的首要场所，其中磷脂酶D（PLD）是细胞内重要的跨膜信号转导酶，在感应和接受低温信号转导中起重要作用。本项目研究低温冷藏过程中冷害发生不同阶段哈密瓜果实PLD活性、基因和蛋白感应和接受低温胁迫的变化情况；磷脂及其代谢产物的变化规律；PLD与其它冷害生理因子的关系及PLD抑制剂对冷害的影响等。探索哈密瓜果实在低温胁迫中，PLD对低温胁迫的感应模式和在冷害中的作用等。本项目的开展有助于丰富和发展采后生理学的理论体系，而且为果蔬贮藏保鲜技术的开发和改进提供重要的理论指导。

哈密瓜属于典型的呼吸跃变型果实，采后后熟衰老迅速，抗病能力下降，腐烂损失严重。低温冷藏能有效抑制果实采后腐烂和品质下降，但哈密瓜果实对低温环境敏感，在低温下贮藏易发生冷害，冷害的发生限制低温贮藏技术在哈密瓜果实采后贮运中的应用，如何增强哈密瓜果实采后对低温的耐受性，控制冷害的发生，已成为哈密瓜果实采后贮运中急需解决的问题。.本项目4个方面的研究内容：（1）草酸诱导哈密瓜果实抗冷和抗氧化变化；（2）细胞膜磷脂代谢规律和磷脂酶D活性及其编码基因在低温胁迫中的变化和表达模式；（3）PLD与其它生理因子的关系研究；（4）PLD抑制剂对冷害的影响等。明确草酸如何通过调控PLD活性、磷脂代谢作用产物、信使物质及酶的基因表达等降低哈密瓜冷害。.已获取到“西州蜜 25 号”哈密瓜CDS序列，正上传至ncbi；探索出PLDß1的作用方式及在草酸诱导哈密瓜采后低温耐受信号传导中的功能和作用；培养博士研究生1名，2022年毕业的在读硕士研究生1名；在国内学术期刊发表见刊科研论文5篇（其中第一标注4篇），其中1篇SCI和1篇EI（已录用）。另投至1篇科研论文至postharvest and technology，目前正处于审稿阶段。但是草酸对磷脂代谢的产物如PA、PI和PC等含量的影响，还不十分明确。目前该实验还在继续研究当中。...