| Spring maize is the main crop in Northwest Rain Fed agricultural area,mainly planted with plastic film mulching.Plastic film mulching significantly increase soil moisture effect,but also has high cost,plastic film pollution problems.The use of corn straw mulching can make use of a large number of residual resources of corn straw,avoid the pollution of the film,and realize the combination of soil moisture conservation and cultivation of fertilizer in the field,which is beneficial to the efficient recycling of resources and the sustainable development of agriculture.In recent years,using corn straw to cover the winter wheat and potato with local strip cover can overcome the contradiction between soil moisture conservation and the reduction of ground temperature,and the effect of drought resistance and increasing yield is remarkable.But maize is a warm crop,and the application effect of straw mulching maize in dry land,especially seed stalk and silage corn,needs to be compared in depth and systematically.Experimental study.The total membrane double ridge furrow white film planting in the whole province was taken as the control(BM),the whole maize straw mulching(JG)and the full film double ridge furrow black film planting(HM)were set up.Studied the effects of different mulching material on yield,growth and soil moisture and temperature under typical natural drought conditions in Northwest China.Three kinds of planting density(52500/ha),fertilization level,variety and field management are the same,the width of straw strip mulching belt and planting zone are 50 cm and 70 cm.The main results are as follows:1.The water use efficiency(WUE),soil moisture and soil temperature of grain yield,biological yield,yield structure factor,growth and development,grain yield and biological yield were significantly different among different mulching cultivation methods(P<0.05).In general,two kinds of film mulching methods significantly improved the grain yield,the yield of straw per mu,the biomass,the water use efficiency of grain yield and the water use efficiency of biological yield compared with JG.The grain yield differences between BM and HM were not significant,but the grain yield of JG was significantly lower than that of BM and HM by 21.1~21.8%,the yield of per mu straw decreased significantly by 8.9~16.5%,the biological yield decreased significantly by 14.5~18.5%,and the grain output WUE significantly reduced 16.7%~30.6% and the biological yield WUE was significantly reduced by 13.1%~24.8%.But the water consumption of BM is the highest and the WUE of HM is the highest.The WUE of grain yieldis greater than that of water consumption.2.The determination of grain weight was greater than grain number per spike,but the grain number per ear and grain weight were significantly positively correlated,indicating that under the current hydrothermal environment capacity and population structure,the two yield components were still at the same time in the northwest dryland.At the stage,there is still a great potential for increasing yield through cultivation.The reduction of JG is mainly due to the sensitivity of corn to temperature.Straw mulching will lead to the decrease of ground temperature,which is closely related to the late greening and grain weight loss.The average temperature of soil 0~25cm in the whole growth period was significantly correlated with the grain yield per unit area and 100 grain weight,and no significant correlation with the number of spikes.3.High yield of maize in dry land was based on good nutrition growth,and grain yield was positively correlated with biomass and plant height,and plant height and biological yield were also positively correlated.The yield difference mechanism was analyzed from the angle of nutrition growth,reproduction and dry matter transfer distribution.The yield between the treatment and the yield was mainly dependent on the biological yield,and then harvest index.The harvest index between different cultivation treatments was relatively stable;compared with JG,the weight of 100 grain,plant height,straw yield and ear position of BM and HM were compared.The height and stem diameter increased significantly,and the length of bald tip decreased significantly.4.HM is not significantly lower than BM,but JG is significantly lower than BM,and the soil temperature of 0~25cm in whole growth period is 1.3 degrees lower than BM,and the average temperature difference of 0~25 cm soil between treatments is maximum at the seedling stage and BM-JG(3.9?).The maximum temperature difference between treatments appeared at 25 cm soil layer at seedling stage,and BM was higher than JG 8?.Although JG and HM had a significant cooling effect compared with BM,JG and HM also had the dual effects of increasing temperature and decreasing temperature with different growth stages and soil layers.In a total of 35 points of time and soil layer determination,JG is 63% lower than that of BM,and there is a double effect in each layer.The cooling effect of JG mainly occurs in sowing ~ sowing stage,and the effect of temperature increase mainly occurs during the flowering period.The average temperature of soil 0~25cm in the whole growth period was significantly related to the biomass per unit area and the yield of straw per mu.It showed that straw strip mulching and black film mulching decreased the soil temperature,but it was not a strong limiting factor to increase the yield of silage.5.JG and HM ‘s average water content of 2m soil in whole growth period are higher than BM's.HM and JG is about 0.7 percentage points higher than BM.Soil moisture generally decreases with soil depth,the water content of 0~20cm soil layer is the highest,and the water content of 150~200cm soil layer is the lowest.The difference in moisture content between treatments was also different.The difference was greatest in silking stage,and the maximum difference in 2M soil moisture HM and JG was 5.1 percentage points.The difference between the soil layer and the soil layer was the biggest difference between the 0~40cm and the 60~120cm,and the maximum difference occurred in the 120~150cm soil layer in the silk spinning period,and the maximum difference of JG and HM was 6.7 percentage points(JG and HM).JG and HM also showed a dual effect than BM moisture and reduced soil moisture.In 7 periods and 8 soil layers,the proportion of HM and JG is 57.1% and 60.7% respectively compared with BM soil moisture.The average soil moisture content is 0.8 and 1.3 percentage points,the soil moisture increasing point is the highest in the upper layer of 0~40cm,at the lower level of 150~200cm,and the middle layer of 90~120cm is more obvious.The average water content in 0~200cm soil during the whole growth period was significantly correlated with the biomass per unit area and the yield of straw per mu.It showed that the effect of straw and black film mulching on biomass and yield per mu was affected by soil water content. 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