Construction of inducing disease resistance by Heteroconium chaetospira

根内生真菌chaetospiura在寄主植物中引起强烈的拮抗反应，这一现象可用于提供对不同种类植物和病原体的抗性。我们发现，当毛毛螺旋体作为前接种物时，当试验植物与这些疾病的致病因子接种后，毛毛螺旋体抑制了黄萎病和棍棒病的发病率。毛毛螺旋体在大白菜根上的定植可以诱导大白菜的全身抗性，减少细菌性叶斑病和互花孢叶斑病的发生。毛毛螺旋体可穿透寄主的外表皮细胞，进入内皮层，并在包括根尖区域在内的皮层细胞中生长。毛毛螺旋体可以长时间生长并持续存在，与其他生物防治剂相比，它受根外微生物相互作用的影响较小。基本的环境条件，包括温度、湿度、阳光和土壤的物理和化学特性，可以极大地影响寄主植物的生理和随后的疾病发展，并以各种方式改变植物、病原体和生物防治剂之间的相互作用。在中低土壤湿度范围内，毛毛螺旋体静止孢子密度为每克土壤10个静止孢子时，是白菜根瘤菌的有效生物防治剂。

Root endophytic fungus Heteroconium chaetospiura is known to induce strong antagonistic responses in host plants and the phenomenon can be applied to provide resistance to different species of plants and pathogens. We found that, when used as a preinoculum, H.chaetospira suppressed the incidence of clubroot and Verticillium yellows when test plants were post-inoculated with the causal agents of these diseases.Furthermore, colonization of roots by H.chaetospira could induce systemic resistance in Chinese cabbage and reduce the incidence of bacterial leaf spot and Alternaria leaf spot. H.chaetospira penetrates through the outer epidermal cells of its host, passes into the inner conxtex, and grows throughout the cortical cells, including those of the root tip region. H.chaetospira can grow and persist for long periods and may be less affected by microbial interactions outside the root then other biocontrol agents. Basic environmental conditions, including temperature, moisture, sunlight, and soil physical and chemical characteristics, can greatly affect the physiology of the host plant and subsequent disease development, as well as alter interactions among the plant, pathogen, and biocontrol agents in various ways. H.chaetospira is an effective bioconrol agent against clubroot in Chainese cabbage at low to moderate soil moisture range and a pathogen resting spore density of 10 resting spores per gram of soil in situ.