不同种植模式对作物根系生长、产量及根际土壤微生物数量的影响

采用多年大田试验研究了小麦-大豆(A1)、小麦-甘薯(A2)、玉米(A3)、小麦/玉米/大豆(A4)和小麦/玉米/甘薯(A5)5种种植模式的根际环境变化特征和根系生长特性.结果表明:与A1、A2、A3和A5相比,A4提高了小麦、玉米、大豆在开花期和成熟期的生物量、根系活力和根干质量,提高了各作物根际土壤细菌、真菌和放线菌数量.各种植模式之间,植株生物量和根际微生物数量的变化规律为套作＞单作、大豆茬口＞甘薯茬口、边行＞中行.小麦/玉米/大豆(A4)套作模式通过改善3种作物的根际环境,促进了作物地下部根系生长和地上部生物量的增加,从而实现作物增产.

Effects of different cropping modes on crop root growth, yield, and rhizosphere soil microbes' number

A multi-year field experiment was conducted to study the variation features of rhizosphere environment and crop root growth under the cropping modes of wheat-soybean (A1), wheat-sweet potato (A2), maize (A3), wheat/maize/soybean (A4), and wheat/maize/sweet potato (A). Among the five modes, A4 increased the plant biomass, root activity, and root dry mass of wheat, maize, and soybean at their flowering and maturing stages, and the quantity of rhizosphere soil bacteria, fungi, and actinomycetes. The biomass and quantity of rhizosphere soil microbes were relay strip intercropping > single cropping, soybean > sweet potato, and fringe row > center row. It was suggested that wheat/maize/soybean relay trip intercropping could improve rhizosphere environment, promote the crops root growth and increase their aboveground biomass, and accordingly, realize yield-increasing.