Research on Rice Cultivation Under No-Tillage with Different Straw Weight of Wheat Return Field in Chengdu Plain

Studied on the impactions of no-tillage and wheat straw returning field to rice yield in Chengdu plain.The studies indicated:(1) The rice yield of no-tillage were higher than rice with conservative tillage .Increased numbers of potent spike was the main reason.(2) Under the no-tillage+wheat straw return field,there was the increased trend that the rice yield of treatment with higher wheat straw return field was higher than others.The relation of rice yield with weight of wheat straw return field accord with the equation,y=7238.6+0.0117x+2.12×10~(-5)x~2-1.49×10~(-9)x~3(R=0.988~(**)).The optimized weight of wheat straw return field was 10 089 kg/hm~2,that rice yield was the highest in all treatments,and then the rice yield was decline exceed the optimized weight.(3) The weeds of no-tillage treatments were increaser than CK in rice growth phase,and weeds were marked decreasing with increasing of the weight of wheat straw return field.After harvest rice,the effect of control weeds was obvious for no-tillage,and the better effect,the more wheat straw of return field.