Study Of Mechanism Of Increasing Yield Of Water-permeability Plastic Film Mulching On Dry Land Sorghum

The experiment design was Latin square about three treatments including water-permeability plastic film mulching, common plastic film mulching and open ground. The experiment studied ecological effect, biological effect, physiological effect, and yield effect on water-permeability plastic film mulching. The result has showed : 1 . The water-permeability plastic film mulching had obvious effect on water-permeability, preserving soil moisture and increasing soil moisture. and its moisture was superior to the common plastic film mulching's and the open ground'sin the whole sorghum growing season ,improving efficiency of water application of dry land sorghum. The effect of temperature-increasing and insulation of water-permeability plastic film mulching was superior to the common plastic film mulching's in sorghum growing prior season. Its soil temperature was lower than the open ground's in sorghum's growing middle and final period,which showed the water-permeability plastic film mulching had the effect of lowering soil temperature slowly. In addition ,the water-permeability plastic film mulching accelerated the conversion of effective nutrient, and its consumption of nutrient substance in growing period was more than the other two treatments'. 2.The water-permeability plastic film mulching promoted the growth and development of all sorghum organs, and its plant height, leafing number, second roots, leaf area, and accumulation of population dry matter were always the highest of the three treatments', so that sorghum of water-permeability plastic film mulching can mature earlier and its first branches'number was larger than the other two treatments'. 3.The water-permeability plastic film mulching increased sorghum leaf's photosynthesis efficacy and strengthened sorghum's resisting adversity,for example,its chlorophyll content, nitric acid reductase content, intercellular co2 concentration, net photosynthesis rate, stomatal conductance, and transpiration rate of sorghum leaves are improved to different degrees,while its praline content and cell membrane relative permeability are lower than the other two treatment's 4.The water-permeability plastic film mulching had eminent effect on increasing yield and income.Its yield was 1403.72kg/hm2 higher than open ground's, increased by...