玉米与马铃薯间作对根际微生物群落结构和多样性的影响

Effects of Maize and Potato Intercropping on Rhizosphere Microbial Community Structure and Diversity

设置3个种植处理(玉米单作、马铃薯单作和玉米马铃薯间作),通过田间试验和盆栽试验,采用Biolog技术分析了玉米马铃薯根际微生物的群落结构和功能多样性的变化情况。结果表明,与单作相比,间作处理使玉米和马铃薯根际微生物对31种碳源的平均利用率(AWCD)分别增加17.36%、7.38%和3.76%、32.21%,其中间作马铃薯的AWCD值最高,单作玉米最低。间作玉米和间作马铃薯根际微生物群落的Shannon指数(H)、Simpson指数(D)、均匀度指数(E)、丰富度指数(S)均高于单作,但在间作和单作之间差异不显著。根际微生物对6类碳源的利用强度以糖类、羧酸类和氨基酸最高,并存在一定的差异。主成分和聚类分析表明,玉米与马铃薯间作改变了根际微生物的群落组成,糖类、羧酸类和氨基酸类碳源是区分单间作处理差异的敏感碳源。说明玉米马铃薯间作改变了根际微生物群落结构组成,提高了根际微生物群落功能多样性。

Field and pot experiments were conducted with three planting treatments （maize monocropping, potato monocropping, maize, and potato intercropping） to investigate the changes of composition and function diversity of rhizosphere microbial com-munity of maize and potato using Biolog technique. The results indicated that compared with monocropping, the average well color development （AWCD, utilization rate of 31 carbon sources） of rhizosphere microbes of intercropped maize and potato was increased by 17.36%, 7.38% and 3.76%, 32.21% respectively, among the intercropping and monocropping crops, the AWCD value of intercropped potato was the highest and the monocropped maize was the lowest. Functional diversity index of Shannon index （H）, Simpson index （D）, Evenness index （E）, and Richness index （S） were higher in intercropping rhizosphere soil than these in the monocropping systems, but no significant difference. Among six types of carbon sources used by the rhizospheric microbes, carbohydrates, amino acids and carboxylic acids, had higher utilization rates with definite differences. Principal com-ponent analysis （PCA） and cluster analysis demonstrated that the amino acids, carbohydrates and carboxylic acids were the sensi-tive carbon sources for differentiating the changes of the microbial community induced by monocropping and intercropping. This study showed that intercropping can change the composition and enhance functional diversity of the microbial community in the rhizosphere of maize and potato.