Effects Of Conservation Tillage On Soil Nutrients And Crop Yield And Grain Quality

Conservation tillage is a recently-developed farming practice in China, which affected cropland deco-environment and the growth of crops. In order to provide a solid technological and theoretical support for light-duty, high yield, good quality and efficient production in crops, Conservation tillage were adopted to study their effects on cropland eco-environment, crop growth, yield and grain quality. The experiment was carried out in 2008 at the Agriculture Science Institute of Taihu, Jiangsu with three cropping patterns (wheat-rice, ryegrass-rice, rape-rice), two modes of tillage and two modes of crop straw returning to field, hence forming 12 experimental treatments. The main results are as follows.1. After several years straw returning, soil organic matter, total N, available P and K in conservation tillage increased by 4.2%,5.6%,9.6% and 25.7%,respectively,compared with that in conventional tillage. Of which, the increments of available K were the biggest .2. Under conservation tillage, the number of spikes per unit area was higher, but the kilo-grain-weight was lower, It could also receive a higher yield. theoretical and actual output were more than the no -straw returning field burning of straw to avoid environmental pollution, with better economic and ecological benefits.3. Based on the average yields for wheat-rice, ryegrass-rice, rape-rice cropping patterns in 2008, The highest rice yield was tillage with straw returning conservation tillage also could obtain a higher yield. In wheat-rice, rice yield was 8991.6kg/hm~2 under conservation tillage, being 6.8% ,7.1% higher than that of straw returning with ploughing, no tillage with no straw returning.In ryegrass-rice, rice yield was 8611.9kg/hm~2 under conservation tillage, being 8.9% ,5.6% higher than that of no straw returning with ploughing, no tillage with no straw returning. In general, the pattern of conservation tillage could increase rice production.4. The wheat test weight under conservation tillage was low, but flour rate was high, with the best commercial quality . while straw returning increased the crude protein content and wet gluten content, which was beneficial to the optimization of wheat commercial quality.5. The cooking quality of the conservation tillage was improved due to the increase of protein, decline of amylase content and the increase of gel consistency of rice starch. But the cooking quality of straw returning with ploughing was reduced.