Bacterial Diversity and Community Structure Characteristics in Rhizosphere Soil of Coconut (Cocos nucifera L.) under Intercropping Pineapple

To explore the bacterial diversity and community structure characteristics of the rhizosphere soil of fruit type coconuts of different varieties under the intercropping pineapple model, the Illumina high throughput sequencing technology was used to detect the composition and diversity of soil microorganisms. Furthermore, the correlation between the physical and chemical properties of soil and the characteristics of the rhizosphere soil community was analyzed. The contents of OM, EC, AN, AP, AK, ACa, and AMg in coconut rhizosphere soil under intercropping were significantly higher than those under coconut monocropping. However, the soil pH value of the intercropping mode decreased significantly. The diversity of bacteria in the rhizosphere soil of coconut intercropped pineapple was higher than that of coconut monocropped. The diversity of bacteria in the rhizosphere soil of different varieties of coconuts was also different: The order of bacterial diversity was JG > JYT > JYO > JH. The dominant bacteria of the rhizosphere soil, in order, were Proteobacteria, Acidobacteriota, Bacteroidota, Verrucomicrobiota, Actinobacteria, Planctomycota, Firmicutes, Gemmatimonadota, Myxococcota, Nitrospirota, which indicated that the composition of bacterial species between intercropping and monocropping was very different. JG, JYO, and JYT had a high similarity of bacterial community through principal component analysis and cluster analysis, and the bacterial community composition of these three treatments was significantly different from that of CH and JH. In addition, JH had significant differences in bacterial community composition compared to CH. This also showed that different varieties of coconut intercropping pineapple have a great impact on the bacterial composition of coconut rhizosphere soil.