Functional response of the fungus Hirsutella rhossiliensis to the nematode, Heterodera glycines  

作　　者：SHU Chi LAI YiLing YANG EnCe CHEN SenYu XIANG MeiChun LIU XingZhong 

机构地区：[1]State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences [2]University of Chinese Academy of Sciences [3]Southern Research and Outreach Center, University of Minnesota

出　　处：《Science China(Life Sciences)》2015年第7期704-712,共9页中国科学（生命科学英文版）

基　　金：supported by the National Key Basic Research Program of China(2013CB127506);the National Natural Science Foundation of China(30800732);the National Public Benefit Research Foundation of China(200903040)

摘　　要：Functional response is a key index in determining the population fluctuation in predation. However, the lack of operable research system limits the studies on functional response of fungal predators. Hirsutella rhossiliensis is a dominant parasite of the soybean cyst nematode, Heterodera glycines. In a soil microcosm bioassay, we determined fungal biomass at different days within 21 days after inoculation, and parasitism rate of H. glycines by the fungus was determined. The functional response of H. rhossiliensis to H. glycines was established and found to be Holling＇s type Ill, which was influenced by mycelial densities. Meanwhile, we conducted anti-fungal analysis of metabolic fractions extracted from H. rhossiliensis to explain the potential mechanism of the intraspecific competition illustrated by functional response. The result of anti-fungal experiments indicated that the fungal predators had more complicated interaction at population level than expected, which might be regulated by self-inhibition metabolite（s）. This study was the first functional response study of fungal predators in microcosm. With the in- creasing recognition of emerging fungal threats to animal, plant, and ecosystem health, the methodologies and hypotheses proposed in this study might inspire further research in fungal ecology.Functional response is a key index in determining the population fluctuation in predation. However, the lack of operable research system limits the studies on functional response of fungal predators. Hirsutella rhossiliensis is a dominant parasite of the soybean cyst nematode, Heterodera glycines. In a soil microcosm bioassay, we determined fungal biomass at different days within 21 days after inoculation, and parasitism rate of H. glycines by the fungus was determined. The functional response of H. rhossiliensis to H. glycines was established and found to be Holling's type III, which was influenced by mycelial densities. Meanwhile, we conducted anti-fungal analysis of metabolic fractions extracted from H. rhossiliensis to explain the potential mechanism of the intraspecific competition illustrated by functional response. The result of anti-fungal experiments indicated that the fungal predators had more complicated interaction at population level than expected, which might be regulated by self-inhibition metabolite(s). This study was the first functional response study of fungal predators in microcosm. With the increasing recognition of emerging fungal threats to animal, plant, and ecosystem health, the methodologies and hypotheses proposed in this study might inspire further research in fungal ecology.

关 键 词：fungal predator predation index self-inhibition composition soybean cyst nematode 

分 类 号：Q934[生物学—微生物学]