Effects Of Deep Tillage And Alternate Border Irrigation On Yield Formation And Water Use Efficiency Of Wheat-maize Two Crops A Year

Rotary tillage in Huang-Huai-Hai Plain was very common. However, manyproblems occurred for winter wheat and summer maize fields with long-term rotarytillage, such as topsoil shallow, crop roots developed shallow, easy to waterlogging ordrought, lowed water use efficiency, and so on, which was not favorable to obtain highyield. In order to solve those problems, tillage methods and irrigation methods wereintroduced in this study. Effects of rotational tillage and alternate border irrigation onsoil bulk density,soil moisture, growth and development，photosynthetic characteristics,dry matter accumulation amounts, yield formation, IUE and WUE of winter wheat andsummer maize were studied. Results showed as follows:1. Deep tillage after long-term rotary tillage significantly reduced soil bulkdensity at10-30cm. After irrigation, DT increased water storage at40~100cm soilby10.76mm. When it is drought, DT reduced water storage at0~40cm soil by2.84mm and the water delivery of DT is better.2. Deep tillage after long-term rotary tillage, significantly improved LAI of wheatand maize, significantly raised the function leaf SPAD value of wheat-maize in latergrowth，improve the stomatal conductance net photosynthetic rate and transpirationrate promoted the plant dry matter accumulation, increased annual dry matteraccumulation by8.58%~19.91%.3. Deep tillage after long-term rotary tillage, significantly increased annual yieldby6.73%~13.03%，and increased annual water use efficiency by12.22%.4. After DT, implement alternate border irrigation, can reduce the irrigation area,irrigation water decreased by40%. Compared with full irrigation, LAI and dry matteraccumulation of wheat and maize was not significantly reduced, the annual productionis only decreased by2.71%, but WUE was increased by11.39%, to27.4kg/hm2/mm. After long-term rotary tillage deep tillage could break the plough layer, promotedwheat and maize growth and development, increased and yield water use efficiency.Alternate border irrigation could significantly increase annual water use efficiency ofwinter wheat and summer maize. It is of great significance to further explore thereasonable tillage methods and improve the farmland irrigation methods, and improvethe grain yield and water use efficiency in Huang-Huai-Hai Plain winter wheat andsummer maize fields.