Biofertilizers are not always applicable for the local environment or specific plant species. Therefore, it is necessary to assess the universal effects of a biofertilizer when applied to different plants across regions. Particularly, how actinobacteria-based biofertilizers affect the assembly of rhizosphere microbial communities remains unknown. Here, the authors assessed the universal validity and regulatory role of a biofertilizer containing Streptomyces pactum Act12 and Streptomyces rochei D74 in reshaping the rhizosphere microbial communities associated with different plants grown in Shaanxi, Inner Mongolia, and Xinjiang of northwest China.
A greenhouse pot experiment was conducted with cucumber, and field experiments were conducted with tomato, pepper, sunflower, and jujube. Compared with the control, biofertilizer application improved the yield of the different plants by 7.7%–55.6%. The community composition of rhizosphere fungi shifted in biofertilizer-treated soils, despite no significant differences in the species diversity or richness of bacteria and fungi. For single plant species, the alpha diversity indices of rhizosphere microbial communities showed distinctly different trends in response to biofertilizer application.
Following biofertilizer application, the relative abundance of some plant beneficial taxa (such as Chitinophaga, Dokdonella, Pseudoxanthomonas, and Coprinellus) increased, while the relative abundance of some phytopathogenic taxa (such as Cladosporium and Gibberella) decreased. Stochastic processes contributed predominantly to the bacterial community assembly, whereas the relative contribution of stochastic processes to fungal community assembly increased by 6.3% under biofertilizer treatment. Biofertilizer application reduced the average connectivity and density of microbial co-occurrence networks and changed some of the keystone genera.
Yulong Li; Haiyang Li; Xue Han; Gang Han; Jiao Xi; Yutao Liu; Yanjiang Zhang; Quanhong Xue; Qiao Guo; Hangxian Lai
Applied Soil Ecology (2022) Volume 171, 104345