水杨酸、壳聚糖互作对葡萄柚采后果实细胞壁代谢调控和抗病性诱导的作用及机制

Deterioration texture quality, fungal infection diseases lead to postharvest grapefruit fruit rot during storage. Traditional fungicide increase drug resistance and pollute the environment. Thus, searching environmental protection and effective disease control storage has become a primary problem in grapefruit industry scale development in Yunnan. In this research, storage diseases pathogenic bacteria will be identified by morphology, ITS and pathogenic detection in grapefruit fruit as the research object. Basis on this study, grapefruit fruits will be treated with SA, CTS single or compound dip treatment, the effect of SA and CTS on keeping the fruit cell wall structure stability, producing disease resistant defensive and interactions of defense signal transduction pathways were studied basis on microstructure, physiology and biochemistry and molecular organism, with TEM, FI-RT, Real-time Quantitative PCR and HPLC-MS detection combination with physical and chemical index measurement analysis. The mechanism of SA and CTS interaction regulation cell wall metabolism, induction disease resistance of the postharvest grapefruit fruit will be revealed. On the theoretical foundation of this research, green and effective grapefruit fruit storage technology will be built. Theoretical evidences will be provided for development and application of SA, CTS at disease control, fresh storage aspects in fruit and vegtable.

采后葡萄柚果实质地劣变、病害侵染致使果实腐烂，传统杀菌剂保鲜易增强果实抗药性、污染环境。因此，寻找环保、有效的病害防治、保鲜贮藏技术已成为云南葡萄柚产业规模化发展亟待解决的首要问题。本研究以采后葡萄柚果实为研究对象，通过形态学、ITS序列和致病性检测，鉴定贮藏病害病原菌。在此基础上，采用水杨酸、壳聚糖对采后葡萄柚果实进行复合浸泡处理，从果实质地特性、抗病能力入手，利用TEM、FI-RT、Real-time Quantitative PCR、HPLC-MS检测结合理化指标测定分析，从显微结构、生理生化、分子生物方面，研究水杨酸、壳聚糖对维持果实细胞壁结构稳定性、产生抗病防御性及防卫信号转导途径互作的影响，揭示水杨酸、壳聚糖互作调控采后葡萄柚果实细胞壁代谢、诱导抗病性的机制。研究成果可建立绿色、有效的葡萄柚贮藏技术方法，为水杨酸、壳聚糖在果蔬病害防治与保鲜贮藏方面的发展和推广应用提供理论依据。

采后葡萄柚果实质地劣变、病害侵染致使果实腐烂，传统杀菌剂保鲜易增强果实抗药性、污染环境。因此，寻找环保、有效的病害防治、保鲜贮藏技术已成为云南葡萄柚产业规模化发展亟待解决的首要问题。本研究以采后葡萄柚果实为研究对象，通过形态学、ITS序列和致病性检测，鉴定贮藏病害病原菌。在此基础上，采用水杨酸、壳聚糖对采后葡萄柚果实进行复合浸泡处理，从果实质地特性、抗病能力入手，利用TEM、HPLC-MS检测结合理化指标测定分析，从显微结构、生理生化、分子生物方面，研究水杨酸、壳聚糖对维持果实细胞壁结构稳定性、产生抗病防御性及防卫信号转导途径互作的影响，揭示水杨酸、壳聚糖互作调控采后葡萄柚果实细胞壁代谢、诱导抗病性的机制。研究结果表明，0.2g/L水杨酸+1.5%壳聚糖复配显著抑制了采后葡萄柚果实青霉病的发病率和病斑扩展。进一步研究结果表明：一方面通过水杨酸、壳聚糖复配处理提高了果实中防御酶的活性和次生代谢物质含量的积累。另一方面通过水杨酸、壳聚糖协同作用维持了果实细胞壁结构完整性，增强了果实抵抗病原菌的入侵和破坏能力。此外，壳聚糖诱抗防卫信号与水杨酸相似，壳聚糖对采后果实抗病性的诱导依赖水杨酸和茉莉酸信号分子的转导，水杨酸、壳聚糖协同作用对转导信号分子具有增效作用。本项目研究成果进一步丰富了水杨酸复合壳聚糖诱导抗病的协同作用机理，为开发新型果品保鲜剂提供理论依据。