Abstract:

To improve the yield and quality of potato and lay a theoretical foundation for the implementation of reducing chemical fertilizers and pesticides, the potato rhizosphere soil in Yuyang Agricultural Demonstration Park of Yulin City was taken as the object, by adding Bacillus subtilis, enzyme bacteria and biochar under the treatment of conventional fertilizer and conventional fertilizer (80%, 90%). The effects on soil microorganisms in potato rhizosphere were determined. High-throughput sequencing technology was used to measure the microbial richness of potato rhizosphere soil under different treatments. The results showed that the high-quality sequences were concentrated in sequence length 400-420 bp and 420-440 bp, and the number of high-quality sequences was 284937 and 183088, respectively. JS80 treatment resulted in the highest microbial species richness in potato rhizosphere soil, while KS80 and J80 treatments were second only to JS80. The Shannon index of potato rhizosphere soil under JS80 and KS80 was increased by 4.5% and 3.6% compared with CK. Based on the common or unique OTU analysis among different treatments, the results showed that the abundance of soil microorganisms in the potato rhizosphere soil was JS80 > KS80 > KS90 > CK > JS90, that is, JS80 and KS80 were better than other treatments. The potato rhizosphere soil microorganism Chloroflexi increased by 7.0% with KS80 treatment. The study showed that the quantity and richness of soil microbial community in potato rhizosphere soil with biochar application were better than those without biochar application. Under the same bacterial fertilizer treatment, the 80% treatment of base fertilizer was better than the 90% treatment, that is, the richness of soil microbial community in rhizosphere soil after JS80 and KS80 treatments was better than other treatments. JS80 and KS80 can be used as base fertilizer in the field experiment.

Key words: Bacillus subtilis, enzyme, potato, rhizosphere soil, microorganism