The Effect Of Coverage Cultivation On Canopy And Yield Of Dry Rice

Mulching cultivation of rice is a new efficient water-saving cultivation technique. It is the main way to develop water-saving agricultural, and to solve the problem of water shortages and food security. So it has great realistic and profound significance. In this experiment, use P88S/1128 cultivar with three coverage cultivation (plastic film cover, liquid membrane cover and straw cover) and a control of bare cultivation, different populations of dry rice were constructed. The effect of the coverage mode on micro-meteorological factor, canopy structure, plant physiological characteristics, yield and agronomic traits were studied, the main conclusions are as follows:(1) Coverage cultivation of dry rice beneficial to the accumulation of dry matter. The dry matter of whole growth period under plastic mulching, liquid film covering and straw mulching were higher 30.68%,16.28% and 18.06% than control, the difference between them were significant. Coverage cultivation can improve the yield of dry rice, the grain number per panicle and ripening percentage were highest under plastic mulching, and the yield was higher 16.81% than control. The valid panicle increased under straw mulching treatment, it's higher 9.59% than control. The study to photosynthesis of leaves have showed that coverage cultivation extended the period of vigorous photosynthesis, increased the overall upper leaf photosynthetic capacity, so it has better features for grains filling more photosynthetic product.(2)Covering methods on dry rice have significant effect on micro-meteorological factors and individual growth. The canopy temperature of dry rice was reduced, especially in the high temperature season; at the same time, relative humidity increased obviously, so it's created a good environment for the groups. There has a strong transpiration of coverage cultivation, leaf temperature reduced, thereby improving the heat resistance of leaves, photosynthetic rate improved significantly. The results show that by optimizing the cultivation methods such as mulching cultivation to build a good group, it can reduce canopy temperature and bottom humidity to improve the capacity to resist heat damage, disease and insect.(3) Through the study to the canopy, we found that coverage cultivation of dry rice can increase groups leaf area index, leaf distribution in space has also been optimized, the most significant effect was under plastic film mulching. Under plastic mulching conditions, the vertical layers of leaves, leaf angle have been enhanced, so improve the light environment of population to sustain photosynthesis effectively. It also has a positive significance to rice pest control and productivity improvement.