文献类型： 外文期刊

作者： Guo, Zhong-Yuan ¹ ; Kong, Chui-Hua ¹ ; Wang, Jing-Guo ¹ ; Wang, Yu-Feng ² ;

作者机构： 1.China Agr Univ, Coll Resources & Environm Sci, MOE Key Lab Plant Soil Interact, Beijing 100193, Peoples R China

2.Heilongjiang Acad Agr Sci, Inst Soil & Fertilizer, Harbin 150086, Peoples R China

关键词： phospholipid fatty acid: PLFA;allelochemical;5;7;4'-trihydroxyisoflavone: genistein;7;4-dihydroxyisoflavone: daidzein;rhizosphere

期刊名称：SOIL BIOLOGY & BIOCHEMISTRY （ 2020影响因子：7.609； 五年影响因子：8.312 ）

ISSN：

年卷期：

页码：

收录情况： SCI

摘要： Despite an increase in the understanding of the soybean isoflavones involved in root-colonizing symbioses, relatively little is known about their levels in the rhizosphere and their interactions with the soil microbial community. Based on a 13-year experiment of continuous soybean monocultures, in the present study we quantified isoflavones in the soybean rhizosphere and analyzed the soil microbial community structure by examining its phospholipid fatty acid (PLFA) profile. Two isoflavones, daidzein (7, 4'-dihydroxyisoflavone) and genistein (5,7,4'-trihydroxyisoflavone), were detected in the rhizosphere soil of soybean plants, with the concentrations in the field varying with duration of mono-cropping. Genistein concentrations ranged from 0.4 to 1.2 mu g g(-1) dry soil over different years, while daidzein concentrations rarely exceeded 0.6 mu g g(-1) dry soil. PLFA profiling showed that the signature lipid biomarkers of bacteria and fungi varied throughout the years of the study, particularly in mono-cropping year 2, and mono-cropping years 6-8. Principal component analysis clearly identified differences in the composition of PLFA during different years under mono-cropping. There was a positive correlation between the daidzein concentrations and soil fungi, whereas the genistein concentration showed a correlation with the total PLFA, fungi, bacteria, Gram (+) bacteria and aerobic bacteria in the soil microbial community. Both isoflavones were easily degraded in soil, resulting in short half-lives. Concentrations as small as 1 mu g g(-1) dry soil were sufficient to elicit changes in microbial community structure. A discriminant analysis of PLFA patterns showed that changes in microbial community structures were induced by both the addition of daidzein or genistein and incubation time. We conclude that daidzein and genistein released into the soybean rhizosphere may act as allelochemicals in the interactions between root and soil microbial community in a long-term mono-cropped soybean field