Abstract:

【Objective】This study was aimed to analyze the no-tillage and cast-transplanting with milk vetch and straw incorporation on the changes of rice yield and soil fertility and the findings provide a valuable reference for popularization and application of the technology of no-tillage and cast-transplantation of rice in the south china paddy rice.【Method】A two-year (2007-2008) experiment was conducted in paddy fields under a double rice cropping system to probe effects of no-tillage and cast-transplanting with milk vetch and straw incorporation on soil physical properties, soil nutrient, soil enzymes activity ,soil microbe and rice yield.【Result】The no-tillage treatment of two years decreased rice yield. Application of organic manure increased the effective panicle and spikelet per panicle, and improved the rice yield; As the time of no-tillage prolonged, worsened soil physical properties. Application of organic manure reduced soil density and improved soil porosity; The no-tillage treatment helped nutrient enrichment in the surface soil layer. Application of organic manure increased soil nutrient, particularly conventional tillage; Significant positive correlations were observed of total N with urease, catalase, polyphenol oxidase and peroxidase activity; Soil analysis showed that the no-tillage field was less than the control, plowed field in total amount of three groups of soil microbes. However, in no-tillage field, the amount of soil bacteria increased, while that of soil actinomycosis and fungi reduced. Application of organic manure increased the number of soil microbes. 【Conclusion】Application of organic manure improved the rice yield. At the same time, it reduced soil density and improved soil porosity, and alleviated the soil compaction caused by long-term no-tillage. It also increased soil nutrient content and soil enzyme activity and improved the environment for the survival of micro-organisms.