Community rhythms of rhizosphere microbiome during the whole life cycle of potato

Abstract:

[Objective] The rhizosphere environment of terrestrial plants is closely related to the microbe in the soil. Accumulating evidences indicate that dynamics of rhizosphere microbial community directly affect plant health and nutrients utilization. Although rhizosphere microbes are useful for increasing crop productivity, their development has been limited due to a lack of understanding of the dynamics of microbiome. The dynamic changes of rhizosphere microbiome in the whole growth period of potato were studied, and the correlation between rhizosphere biomarkers and potato developmental stage was discussed here. This study will lay foundation for the development of special bio-probiotic fertilizer for different developmental stages of potatoes.[Methods] This study focused on the microbial dynamics of the whole life cycle of potato in field. The Illumina MiSeq high-throughput sequencing technology was used to sequence the 16S rRNA gene V3-V4 region and the fungal ITS region of potato rhizosphere microbe at different time points and to classify the OTUs, in order to analyze the diversity characteristics of microbial communities between samples, and we also established a model through machine learning to correlate rhizosphere microbes with potato development stages in the field. [Results] The rhizosphere microbiome changed significantly with developmental stages. The microbial community structure in the vegetative growth stage changed significantly and it gradually stabilized at beginning of the reproductive stage, and the rhizosphere microbiome varied a lot in the late stage of tuber maturity. In addition, 22 bacterial biomarkers and 16 fungal biomarkers associated with potato development stages were identified based on the model, which are the biomarker Clostridium in seedling stage and Actinobacteria in tuber matured stage. [Conclusion] The growth and development period of potato is the main factor affecting the composition of rhizosphere microbial community. The addition of probiotic fertilizer has a certain effect on maintaining and stabilizing the rhizosphere bacterial community in the late development stage.