华北平原冬小麦夏玉米轮作体系下的土壤丝孢真菌物种多样性

The winter wheat and summer maize rotation system in the North China Plain played an important role in the grain production in China, especially for wheat and maize. However, the problem of plant disease accumulation by straw returning caused great damage to the grain yield and quality. Hyphomycetes was a great group of fungi in the soil, including cellulose degradation species and plant pathogens. Screening and utilization of the hyphomycetes promoting the rapid straw decay is the key to solve this problem. The project intends to investigate the Hyphomycetes in soil with wheat-maize rotation system by cultured method, in order to get the straw rapid decomposition species and biocontrol for the important pathogens. Based on this, the project will explore the trend of Hyphomycetes in the winter wheat-summer maize rotation soil using the method of cultured and metabarcoding, and focus on the trend of two major pathogens (Fusarium and Bipolaris) influenced by crop growth stage, with the combination of disease index, which will help us to ensure what relationship between the number of pathogens in soil and the disease index, so as to provide important data for prediction of wheat-maize important disease.

华北平原的冬小麦夏玉米轮作体系在我国粮食安全尤其在小麦玉米的生产中起在着重要作用，但该体系下的秸秆还田耕作方式带来的病害积累问题给粮食产量以及品质造成了很大破坏。土壤丝孢真菌包括重要的纤维素降解菌和植物病原菌，而促进秸秆快速腐烂的真菌的发掘是解决这一问题的关键核心。本项目拟选取这一种植体系下的土壤作为研究对象，旨在通过平板培养法挖掘其中的土壤丝孢真菌物种资源，为筛选秸秆快速腐解菌和重要病原菌的生防资源积淀材料。同时通过可培养和免培养结合的方法定点检测该地区冬小麦-夏玉米轮作体系下的土壤中丝孢真菌的变化趋势，尤其是两个主要病原属（镰刀菌属和平脐蠕孢菌属）随着作物生长阶段的变化趋势，同时结合病害调查，找到土壤中两属病原菌变化状况和小麦玉米病害发生程度的关系，揭示土壤中菌原的数量变化对病害发生的影响规律，以期为小麦玉米重要病害的预测预报提供参考数据，进一步为病害的防控贡献对策。

华北平原的冬小麦夏玉米轮作体系在我国粮食安全尤其在小麦玉米的生产中起在着重要作用，本项目选取了这一种植体系下的土壤作为研究对象，旨在通过平板培养法挖掘其中的土壤丝孢真菌物种资源,对河南省的81个县市进行土样采样，分不同季节和作物生长阶段。共采集土样430份，收集菌株663株，经过形态学结合分子信息从中鉴定出23属，27种，其中有3个新种和1新记录种。宏测序中，小麦田块物种多样性指数明显高于玉米季节，并且高于其他作物地块。对于小麦常见重要病原菌的测定，有少量的镰刀菌，没有 Bipolaris菌种; 另外，发现1株葡萄穗霉（Stachybotrys sp.）菌株对小麦赤霉病原（禾谷镰刀菌）和根腐病原菌（Bipolaris sorokiniana）具有明显的抑菌效果的土壤生防真菌，有望对其进行生防潜力的挖掘。