Rhizosphere bacterial community in watermelon-wheat intercropping was more stable than in watermelon monoculture system under Fusarium oxysporum f. sp. niveum invasion
Although intercropping and pathogen invasion can affect the plant rhizosphere bacterial community, how intercropping affects the rhizosphere bacterial community in response to pathogen invasion is poorly understood.
The root system of watermelon was separated into two halves and placed in separate pots for Fusarium oxysporum f. sp. niveum(FON) inoculation and wheat intercropping. Responses of the watermelon rhizosphere bacterial community to wheat intercropping and FON inoculation were analyzed by high-throughput sequencing.
Wheat intercropping did not affect the diversity but altered the composition of rhizosphere bacterial community on both sides of watermelon roots. In watermelon monoculture, FON inoculation increased the diversity of the rhizosphere bacterial community and stimulated certain potentially plant beneficial bacteria. The effects of FON inoculation on the watermelon rhizosphere bacterial community diversity and composition in watermelon-wheat intercropping were weaker than those in watermelon monoculture. No contact between wheat and FON was required to decrease the disease index of Fusarium wilt.
The effects of wheat intercropping and FON inoculation on the watermelon rhizosphere bacterial community were mostly plant-mediated, and under FON invasion the rhizosphere bacterial community was more stable in watermelon-wheat intercropping than in watermelon monoculture.
KeywordsBacterial community Fusarium wilt Intercropping Watermelon Wheat
Fusarium oxysporum f. sp. niveum
This work was supported by the National Key Research and Development Program of China (2018YFD1000800), the National Natural Science Foundation of China (31471917), and the Natural Science Foundation of Heilongjiang Province (YQ2019C009).
Fengzhi Wu and Xingang Zhou designed the study. Hongjie Yu and Xiaoxiao Zhang performed the experiments. Hongjie Yu and Shaocan Chen analyzed the data and wrote the manuscript.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
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