| Abstract:In order to investigate the effect of subsoiling on soil characteristics and yield formation of cotton field in oasis area of Xinjiang, no subsoiling cotton field was taken as control (SST0)，under subsoiling treatments of 30 cm (SST1), 40 cm (SST2) and 50 cm (SST3), soil indexes and yield formation characteristics at key growth stages of cotton under different subsoiling depths were studied under the conditions of straw returning to field and conventional tillage.The results showed that subsoiling could reduce soil bulk density and soil hardness, increase soil water content, and decrease soil salt salinity in plough layer. Compared with SST0, under treatments of SST1,SST2,SST3 ,the average soil bulk density at 0-60 cm soil layer decreased by 0.84%,3.94%,4.78%,respectively, and the soil hardness decreased by 1.84%,9.49%,16.57%,respectively.At the 0-30 cm soil layer of bud stage and flowering and boll stage, SST2 had the highest soil moisture content,increasing by 31.00% and 64.50% compared with SST0, while the change of soil salt salinity was opposite.SST2 was the lowest, decreasing by 11.10% and 19.10% compared with SST0. When the subsoiling depth was 40 cm, the maximum dry matter accumulation rate Vm and growth characteristic value GT reached the peak, and the yield of SST1,SST2,SST3 increased by 0.26%,18.20%,2.45%,respectively, compared with SST0. In conclusion, 40 cm of subsoiling is better, has positive effect on improvement of soil properties and yield of cotton in Xinjiang. |
