陆地棉谷胱甘肽硫转移酶亚基编码基因GhGST的抗黄萎病功能研究

Cotton Verticillium wilt is an important disease in cotton production. Resistance gene cloning and genetic transformation are much essential for improvement of the cotton resistance. A tau Glutathione S-transferase (GST) subunit encoding gene, named GhGST, was isolated in our preliminary experiments. The marked Verticillium wilt resistance was observed in transformed tobacco plants. In this study, the functional analysis of the gene will be furtherred, to analyze the temporal and spatial expression in resistant Gossypium barbadense, resistant G. hirsutum and susceptible varieties; to construct GhGST-pBI121 overexpressing vector and RNAi recombinant vector and transform cotton for analyzing the resistance of transgenic plants under Verticillium dahliae stress; to investigate the effects of GhGST overexpression on ethylene(ET), salicylic acid(SA) and hydrogen peroxide(H2O2), and verify how the gene functions in cotton Verticillium wilt resistance. The results will provide important scientific basis to cotton breeding of Verticillium wilt resistance in theory and practice.

棉花黄萎病是生产上的重要病害，抗病基因的克隆与转化对改良棉花黄萎病抗性具有重要意义。项目组在前期工作中，克隆了tau类谷胱甘肽硫转移酶亚基编码基因GhGST，初步研究表明转GhGST基因烟草对黄萎病具有很好的抗性。本项目拟对已克隆的GhGST基因进行深入的功能分析。研究GhGST基因在海岛棉抗性品种、陆地棉抗感品种中的时空表达规律；构建GhGST基因的超表达载体和RNAi载体，获得转基因棉花，研究其黄萎病菌胁迫下基因表达和黄萎病抗性反应；进一步分析GhGST基因超表达对抗病相关内源性激发因子乙烯、水杨酸和过氧化氢表达量的影响；明确GhGST基因对棉花黄萎病的抗病作用及机制。研究结果对棉花抗黄萎病育种具有重要的理论和应用价值。