Influence of Chinese Milkvetch {Astragalus sinicus L.) with No-tillage on Soil Biotic Factors and Rice Yield

摘要

The bacterial community, biotic factors, and rice yield of Chinese Milkvetch (Astragalus sinicus L.) with no-tillage and conventional chemical fertilizer treatment were evaluated. Analysis of bacterial isolates from each treatment plots with 16S rDNAsequences revealed 486 isolates from 18 different bacterial species. The frequency of spore-forming bacteria, including Bacillus sp. and some Actinomycetes appeared to be high under low temperature conditions, whereas Proteobacteria disappeared at low temperature. Most extracellular hydrolytic enzyme activity showing bacteria belong to low G + C Gram(+) bacteria (LGCGPB) compared to high G + C Gram(-) bacteria (HGCGPB) and Proteobacteria. In addition, the total soil carbon content in Chinese Milkvetch treated soil was higher than that of conventional tilled soil samples. Rice yield was slightly higher in the conventionaltilled field (4.13±0.08 Mg/ha) compared to the Chinese Milkvetch-treated field (3.94±0.15 Mg/ha). However, the field treated with Chinese Milkvetch followed by no-tillage was effective in sustaining LGCGP bacterial species that promote biogeochemical cycling and enrich microbial biomass on paddy soil (3.94±0.15 Mg/ha). These results showed that the Chinese Milkvetch treatment with no-tillage is effective in conserving the soil environment without significant yield loss.