关键词: 桑树, 青枯病, 根际, 细菌, 真菌

Abstract: To explore and utilize the abundance of microbes in soil and their benefit functions for bio-control bacterial wilt, soil microbial community structure and soil fertility in rhizospheres between infected and noninfected mulberry plants were analyzed. The results showed that the activities of β-glucosidase and phosphatase in rhizosphere soil of mulberry plants infected with bacterial wilt were all significantly decreased. Meanwhile, the soil microbial biomass carbon, phosphorus in rhizosphere of mulberry plants infected with bacterial wilt also showed the same trend. Moreover, compared to the bacterial wilt non-infected plants, the proportions of some dominant bacteria at phylum level, such as Acidobacteriota, Actinobacteriota and Verrucomicrobiota were all decreased, but the proportions of Proteobacteria, Chloroflexi, Myxococcota, Firmicutes and Bacteroidota were all increased in rhizosphere soil of bacterial wilt infected plants; In contrast with rhizosphere soil of bacterial wilt non-infected mulberry plants, even though Nitrospira and Actinomarinales were the dominant bacterial genera, but also disappearing Streptomyces, which antibiotics could be secreted from it in rhizosphere of bacterial wilt infected mulberry plants. Compared with the bacterial wilt non-infected plants, the proportions of Ascomycota and Basidiomycota increased, but unclassified_k_fungi and Mortierellomycot decreased in rhizosphere soil of the bacterial wilt infected plants at phylum level of fungi. Meanwhile, the proportions of Geotrichum, Humicola and Scedosporium, which belong to saprophytic fungi increased; Mortierella, Acremonium and Aspergillus, which can produce antibiotics decreased in the rhizosphere soil of bacterial wilt infected plants. It suggested that these factors, such as the activities of β-glucosidase and phosphatase, soil microbial biomass carbon, phosphorus and microbial community structure are all closely related to the mulberry plants which infects the bacterial wilt or not. And Streptomyces, Mortierella, Acremonium, Aspergillus can be considered as the benefit microbes for bio-controlling bacterial wilt.

Key words: mulberry (Morus alba L.), bacterial wilt, rhizosphere, bacteria, fungi