Effect Of Different Crop Rotation On The Microorganisms Quantities And Enzyme Activities In The Soil

In this experience, continuous cropping crops as a control, research on the change ofmicroorganism quantity and enzyme activity in different rotation and leisure soil. Selectedcrops varieties: potatoes (Xindaping), wheat(Longchun27), peas (Longwan1). Respectivelycollect the soil sample in different growth period of potato (seedling stage, budding stage,coated, tuber formation, starch accumulation stage and harvest), wheat (jointing stage, youngflowering and maturity), peas (flowering period, grouting period, mature period). Croprhizosphere soil and leisure plot is determined by dilution plate method, by the methods of3,5-2nitro salicylic acid, phenol sodium colorimetry, KMnO4titration and adjacent benzenephenol colorimetric method to determine the rhizosphere soil invertase activity and ureaseactivity and the activity of catalase and polyphenol oxidase activity. The results show that:(1) In general, the coated of potato, wheat and peas mature, soil microbial quantity werehighest in the rhizosphere soril; Trend before, after a downward trend.(2) After2years of continuous cropping potatoes, when peas insert the rotation, thetotal number of bacteria in the soil is higher than others, the total number of bacteria ofpotato continuous cropping3years is higher than leisure plot in the soil, but both are lowerthan the processing of the insertion of wheat, peas. Fungi quantity of potato continuouscropping3years, fungi quantity were highest in rhizosphere soil,58.07%higher than theleisure plot, followed by the insertion of pea crop rotation, leisure plot with a minimum. Thenumber of actinomycetes different from crop rotation in the soil, the insertion of wheatprocessing number of actinomycetes in the soil close to the leisure plot, the potatocontinuous cropping3years compared to the processing of peas insert rotation, theprocessing of peas insert rotation is higher than leisure plot.(3) Wheat and pea insert crop rotation, higher total number of bacteria in the soil, thenumber of bacteria of potato continuous cropping4years were the lowest in all processes inthe soil. In the soil the number of fungi quantity of each process increased a little, comparedwith fungi number of last year and the potato continuous cropping4years increases fast thanthe other processing, the number of fungi quantity were lower in leisure minimum, compared with the last year, increase slow than other processing. compared with the potato continuouscropping3years, the potato continuous cropping4years has more soil actinomycetes,previous for crop wheat and pea, the total actinomycetes quantity of potato in rhizospheresoil emerge rise trend; Previous for crop wheat, the change of actinomycetes number in therhizosphere soil is not obvious.(4) After2years of continuous cropping potatoes, peas insert the rotation of the rotationprocessing and potato continuous cropping3years in the soil invertase activity were higherthan leisure plot; wheat insert the rotation, the soil invertase activity is higher than peas,potatoes. The processing of wheat insert the rotation, catalase activity is higher inrhizosphere soil, but are close to the leisure area, the difference is smaller. Compared withlast year,2013in the soil invertase activity and crop of the world, except for the processingof potato continuous cropping4years, invertase activity was increased in the rest of theprocessing. And leisure plot appear small variations. Wheat Insert crop rotation and thepotato continuous cropping for4years, soil catalase has increased in soil, the former isslightly higher than the latter, the rest of the process compared with the preceding crop,showed a trend of decrease, the insertion of pea crop rotation and leisure plot in the soilcatalase activity slowly. Urease and the activity of polyphenol oxidase as the previous cropchange, but the difference is not significant between the groups, so the former crop has littleeffect on current crop.