小麦和大豆茬口对黄瓜土壤微生物生态特征的影响

Effects of wheat and soybean stubbles on soil microbial ecological characteristics in cucumber field.

采用常规稀释平板法和BIOLOG ECO微平板反应系统,研究了小麦和大豆茬口对黄瓜土壤微生物生态特征的影响.结果表明,两种茬口均显著提高了黄瓜土壤微生物真菌、细菌和放线菌的数量,显著降低了尖孢镰刀菌黄瓜专化型的数量(P<0.05);显著提高了土壤微生物群落的Shannon-Wiener指数、均匀度指数、Simpson指数和McIntosh指数(P<0.05)、以及土壤微生物生物量碳,降低了土壤基础呼吸和代谢商(P<0.05),改变了土壤微生物对单一碳源的利用能力.此外,两种茬口还显著提高了土壤中速效磷和速效钾含量,以及黄瓜产量.说明小麦和大豆茬口改善了土壤微生态环境.

The study with traditional dilution plate method and BIOLOG ECO system indicated that under wheat and soybean stubbles, the amounts of soil fungi, bacteria and actinomyces in cucumber field increased, while that of Fusarium oxysporumf, sp. cucumerinum decreased （P 〈0. 05 ）. The Shannon-Wiener index, evenness index, Simpson index, and McIntosh index of soil microbial communities as well as soil microbial biomass C increased （P 〈 0. 05 ）, basal respiration and metabolic quotient qCO2 decreased （P 〈0. 05）, and soil microbe＇s sole-carbon-source utilization enhanced. In addition, the contents of soil available P and K and the cucumber yields were also increased markedly. All of these illustrated that wheat and soybean stubbles improved the ecological environment of soil microbes.