Correlation Between Rhizosphere Soil Properties and Microbial Communities of Different Coffea arabica Cultivars

This study investigated the differences in rhizosphere soil properties and their associations with microbial communities across eight Coffea arabica cultivars cultivated under uniform conditions at the Kangping Education and Research Base in Pu’er, Yunnan. We assessed arbuscular mycorrhizal fungi (AMF) colonization and spore density, analyzed soil chemical properties—including pH, organic matter (OM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), alkali-hydrolyzable nitrogen (AN), available phosphorus (AP), available potassium (AK), and slowly available potassium (SK)—and characterized microbial communities via high-throughput sequencing. The findings of this study demonstrate that coffee variety significantly influences the contents of available nutrients (AN, AP, AK) and OM in the rhizosphere soil. Sequencing indicated that Ascomycota dominated the fungal community, Chloroflexi and Proteobacteria were the primary bacterial phyla, and Glomus and Sclerocystis were the predominant AMF genera. Analysis of alpha diversity showed that in the bacterial community, S8 exhibited the highest diversity and richness, while S6 showed the lowest. For the fungal community, S6 had the highest diversity, S2 displayed the highest richness, and S5 showed the lowest values for both diversity and richness. Within the AMF community, S8 demonstrated the highest diversity, S7 exhibited the highest richness, and S6 had the lowest diversity and richness values. Overall, bacterial diversity surpassed fungal diversity. Redundancy analysis identified AK as a common key factor influencing both bacterial and fungal communities. Besides AK, OM and TN were also significant drivers for the fungal and bacterial communities, respectively, while the AMF community was most strongly associated with SK