Effects of different mulching materials on rice yield in transplanting field with semiarid cultivation method

In order to study the effects of different straw materials on hybrid rice yield,we carried out a 3-year field experiment at the scientific research bases of SWUST.Based on the data from this experiment,we analyzed the impacts of different straw mulching materials on the number of stem and tillers,the accumulation of dry matter of rice and the soil water content in 0～0.5m soil layer.The results showed that:(1) Straw mulching was conducive to increase the soil water storage in 0～0.5 m soil layer during none irrigation period,therefore straw mulching promoted the increase of the number of stems and tillers in transplanting field.The nutrition,coming from the decomposition of straw mulch,relieved the nutrition shortage in rice field.Therefore,the seed setting rate,number of effective panicles and weight of 1000 grains all increased under straw mulching treatments,compared with that under no mulching treatment.Soil water storage in 0～0.5 m soil layer increased by 2%～3%,seed setting rate by 4%～15%,number of effective panicles by 4%～8%,weight of 1000 grains by 0.6%～1.7% under straw mulching treatments,compared with that under no mulching treatment.(2) Integrated with semiarid cultivation method,straw mulching method could significantly increase rice yield in transplanting field in the northwest region of Sichuan Province.The average yield of Gangyou 725 and Dyou 363 under mulching treatments with rapeseed husk,winter wheat husk and winter wheat straw increased by 10.2%,7.0% and 7.7% respectively,compared with that under no mulching treatment.