Dynamics Change of Dry Matter Accumulation and Relative Characteristics of Spring Wheat under Different Tillage

In order to improve the grain yield of spring wheat in arid areas,field experiments were carried out on the Xinjiang Uygur Autonomous Region.The effects of four different tillage treatments on wheat dry matter accumulation of each organ and grain yield were studied.The four different tillage treatments were conventional tillage(CT),conventional tillage with straw mulching(CS),no-till with no straw mulching(NT) and no-till with straw mulching(NTS).The major results showed that the change of total dry matter accumulation of Xinchun 6 was consistent with the typical S curve.The four different tillage treatments all reached maximum values at 30 d after anthesis.Compared with conventional tillage(CT),the maximum dry matter accumulation amounts of CS,NT and NTS treatments were increased by 15.40%,24.58% and 35.17%,respectively.The effect of different treatments on total ADM increasing rate was in the following order:NTSNTCSCT.The treatments of CS,NT and NTS could improve the growth of spring wheat and were responsible for improvement of their yield,with increasing 14.68%,31.57% and 45.92% respectively compared with the convention tillage.No significant differences were found between the treatments of NT and NTS,but there were significant differences among other treatments.Overall,the results showed that the comprehensive characters were most superior by the treatment of NTS.The rates of dry matter distribution among different organs of spring wheat were changed and harvest index was enhanced.Therefore,the ratio of the grain yield to biomass was higher than the others.At the same time,no-till with straw mulching(NTS) could enlarge the grain filling rate and extend the duration of grain filling,which was enhancing the transportation of the photosynthate after anthesis.