水稻抗褐飞虱基因多样性持续控制褐飞虱的分子机理

Biology diversity is essentially attributed to the genetic diversity. Revealing relationship between resistance genes in crop and virulence genes in insect provides a critical basis for understanding the mechanism of crop diversity in controlling insect pests. Brown planthopper (Nilaparvata lugens, BPH) is one of the most destructive insect pests of rice (Oryza sativa) in the world. BPH is a typical piercing-sucking herbivore and different biotypes have been found in this insect. Rice is a model organism and more than 20 BPH-resistance have been identified in rice germplasm. In the applicant laboratory, BPH-resistant rice varieties that carry different BPH-resistance genes and BPH populations with different virulence to rice varieties have been developed, that form an ideal system for studying the effect of host resistance genes diversity in controlling insect pests in agriculture. In this program, we will employ the functional genomics methods to isolate BPH-resistance genes in rice and to identify HAMP or effector in BPH. Perceiving BPH by resistance gene, signaling and defensive responses that occur in rice plant will be studied. We will further elucidate the effects of rice resistance on BPH population and mechanism for virulence variation in this insect. The results will contribute to development of durable resistant rice variety for sustaining control of BPH pest in rice crop.

生物多样性的重要内涵是遗传基础的多样性。深入研究作物不同抗性基因与害虫种群及其致害性基因的关系，是理解作物多样性对害虫调控作用机制的重要内容。褐飞虱是我国水稻生产中发生和为害面积最大的害虫，培育和种植抗性品种是防治褐飞虱的经济、有效途径。水稻是单子叶模式植物，已经鉴定了多个抗褐飞虱基因；褐飞虱是典型的刺吸式口器昆虫，已分离出多个生物型群体；二者组成了研究作物抗性基因多样性对农业害虫调控机理的理想体系。申请者实验室已经培育了多个抗褐飞虱水稻材料和褐飞虱实验种群，本项目运用功能基因组学综合研究手段，分离水稻不同位点的抗褐飞虱基因，鉴定褐飞虱HAMP或效应子，研究水稻抗褐飞虱基因对褐飞虱取食的识别和防卫分子机理，从分子水平上阐明水稻抗性对褐飞虱种群的调控作用以及致害性发生变异的机制。研究结果将为培育具有稳定抗性的水稻品种和实现褐飞虱持续防控提供理论依据和基因。

本项目按照计划开展了抗褐飞虱基因克隆与分析、褐飞虱致害性变异的分子基础、水稻抗褐飞虱的分子机理和水稻抗性对褐飞虱的作用等四个方面的研究。应用图位克隆法分离了Bph6、Bph9及其等位基因Bph1、Bph7、Bph10和Bph21，揭示了抗褐飞虱基因等位变异是水稻应对褐飞虱致害性变异的重要策略。本项目还鉴定出了褐飞虱效应子NlMLP并解析了其功能，从代谢组方面揭示了水稻对褐飞虱的作用。鉴定和定位了褐飞虱致害性基因位点。论文研究结果发表SCI论文10篇，产生了较广泛的国际影响，为利用抗褐飞虱基因多样性持续控制褐飞虱这一重大农业害虫奠定了理论基础并提供了基因资源。本项目在实施过程中，申请和获得了抗褐飞虱基因相关发明专利多项，创制了带有上述抗褐飞虱基因的新种质，提供给育种家用于水稻抗虫育种，取得了显著的效果。