新疆绿洲棉田黄萎病发生与根内微生物群落结构的相关性研究

Verticillium wilt, a serious disease which threatens cotton-growing industry in Xianjiang region, has caused huge economic losses in local cotton production. It is proved that close relationship exsits between the occurrence of Verticillium wilt and soil (rhizosphere soil and bulk soil) microbial community structure, however, no study on the correlation between occurrence of Verticillium wilt and community structure of endophytic microorganisms in cotton roots has been reported. In this tudy, the methods of isolation and culture will be combined with Denaturing Gradient Gel Electrophoresis (PCR-DGGE) to analyze the community structures of endophytic microbes in roots of a main cultivar, Gossypium hirsutum L. cv. XINluzao NO.33 grown in fields on different level of Verticillium wilt severity (mild disease fields of Nongba Division 143rd Regiment, mild disease fields of Nongba Division 145th Regiment, moderate disease fields of Nongba Division 147th Regiment and severe disease fields of Nongba Division 143rd Regiment) in Xinjiang region, moreover, the endophytic microbial community structure dynamic variation with growth stages (seeding stage, budding stage flowering stage and boll stage) will be resolved simultaneously under the condition metioned above by the same methods as well, according to which the correlation between occurrence of Verticillium wilt and community structure of endophytic microorganisms in cotton roots will be determined. Not only will the implementation of this study be useful to reveal the relationship between occurrence of Verticillium wilt and community structure of endophytic microorganisms in cotton roots, but also will be helpful to explore the biocontrol resource in cotton roots.

棉花黄萎病是威胁新疆地区棉花种植业的一种重要病害，已给当地棉花生产造成了巨大的经济损失。已有研究表明，棉花黄萎病发生与根际及土壤微生物群落结构之间具有密切的关系，但是棉花黄萎病发生与根内微生物群落结构的相关性研究尚无报道。本项目拟采用微生物的分离培养与变性梯度凝胶电泳（PCR-DGGE）相结合的方法，并借助Biolog MicroStation系统鉴定分离获得的微生物，对新疆地区黄萎病发生程度不同的棉田（农八师143团轻度病田、农八师145团轻度病田、农八师147团中度病田及农八师143团重度病田）中种植的新陆早33号棉花品种（主栽品种）根内微生物群落结构及其随棉花不同生育时期（苗期、蕾期、开花期与结铃期）的动态变化规律进行解析，明确棉花黄萎病发生与棉花根内微生物群落结构的相关性。该项目的实施不仅有利于揭示棉花黄萎病的发生与根内微生物群落结构的关系，而且有助于挖掘棉花根内的生防菌资源。

本项目采用了微生物的分离培养与变性梯度凝胶电泳（PCR-DGGE）相结合的方法，以新陆早33号为研究对象，对新疆地区黄萎病发生程度不同的棉田（农八师石河子市143团14连2-1号地为无病田，145团6连南3号地为轻病田，147团7轮4号地为中度病田，143团14连北2-4号地为重病田）中种植的新陆早33号棉花品种（主栽品种）根内微生物群落结构及其随棉花不同生育时期（苗期、蕾期、开花期与结铃期）的动态变化规律进行解析，明确了棉花黄萎病发生与棉花根内微生物群落结构具有明显的相关性，共计分离出1549株内生细菌、702株内生真菌和211株内生放线菌，结合变性梯度凝胶电泳分析来看，研究结果显示不同发病棉株的内生细菌大多数属于变形菌门，内生放线菌的群落结构多样性与棉花生长发育密切相关，且健康棉株较发病棉株丰富，表明黄萎病菌侵入影响了内生细菌和放线菌的群落结构；内生真菌多数属于半知菌类和子囊菌门，棉花生长中后期，轮枝孢属真菌数量增加，表明黄萎病菌的侵染能够影响发病棉株中后期的内生真菌群落结构多样性。. 项目组经过4年的刻苦攻关，协同工作，顺利完成了任务书规定的各种指标，参加编写专著2部，标注项目编号发表论文4篇。申请并授权发明专利1项，实用新型专利1项，作为联合培养硕士研究生导师培养研究生2名。该项目具有较为良好的应用前景，建议基金委继续资助相关研究。