Study On Grout Dehydration Characteristics Of Maize Hybrids With Different Ripening Stages At Different Densities

The yield An important influencing factor of corn grain yield is the limitation of dry matter accumulation in the kernel,However,the grout process serves as an important process for the accumulation of dry matter in the grain.The impact on production is even more dramatic.This in turn has an impact on yield.Planting density is one of the factors affecting yield.Therefore,it is of great significance to study the grain filling process of maize at different densities to improve maize yield.With the The whole process of maize production is mechanized,and the moisture content of the corn grain is required at harvest,and the current planting density in Northeast China is 60,000 plants/hm~2,so it is of great significance to study the grain filling and dehydration characteristics of maize hybrid seeds at different ripening stages at different planting densities to select and breed excellent germplasm suitable for mechanized harvesting.In this experiment,three different densities were set up,and the corn hybrids Demeiya 3,Jidan 27,Xianyu 335 and Zhengdan 958 at different ripening stages were selected to Study its grout and dewatering characteristics and yield performance.The results of the study are as follows:(1)The results of grouting characteristics hybrids with different densities and different ripening stages showed that the Logistic model fit the seed filling process of maize well.The grouting process shows a"slow-fast-slow"characteristic.The accumulation of dry matter of grains was mainly concentrated in the rapid growth period of grouting,and the duration of the rapid growth period of filling had a greater effect on the quality of 100 grains than that of the gradual increase period.The grouting rate showed a rapid increase period>a gradual increase period>a slow increase period.The effect of planting density on grain filling rate,increasing planting density,and decreasing grain filling rate.The early maturing variety Demeyer 3 reached the maximum grouting rate at 75,000plants/hm~2,and the growth was larger at the maximum grouting rate.In other periods,Jidan 27,Xianyu 335 and Zhengdan 958 reached the maximum grouting rate at a density of 60,000plants/hm~2,and the growth was larger at the maximum grouting rate and maximum grouting rate.The planting density had a great influence on the grouting rate of each cultivar,and the optimal planting density of the early maturing hybrid Demeyer 3 was 75,000 plants/hm~2,and the optimal planting density of other mature hybrids was 60,000 plants/hm~2.(2)The water content and dehydration characteristics of hybrid seeds at different ripening stages at different densities gradually decreased with the increase of post-pollination time,among which the grain water content of the early maturing variety Demeyer 3 It declines rapidly around 20 days after pollination and stabilizes at 40 days after pollination。Early maturing maize varieties had the fastest grain water content decline rate at 75,000 plants/hm~2.Other ripening varieties decreased rapidly at 60,000 plants/hm~2.The dehydration rate of hybrid seeds at different densities at different densities decreased fluctuating 15-45 days after pollination.The early maturing variety Demeyer 3 had the highest rate at a density of 75,000 plants/hm~2at 20-25 days after pollination.Jidan 27 had a larger rate of 25-30 d after pollination at a density of 60,000 plants/hm~2,while Xianyu 335 and Zhengdan958 had a larger rate of 15-20 d after pollination.The filling rate was negatively correlated with the water content of the grain.The dehydration rate of grain was positively correlated with grain water content.(3)The analysis of yield factors of hybrids at different densities at different times showed that Demeiya 3 and Zhengdan 958 had the highest yields at a planting density of 75,000plants/hm~2,at 10319kg/hm~2and 11230kg/hm~2.Jidan 27 and Xianyu 335 both had the highest yields at a planting density of 60,000 plants/hm~2,with the highest yields of 9538kg/hm~2and9578kg/hm~2.All four varieties had the lowest yield of 90,000 plants/hm~2.Therefore,the planting density of the current main varieties should not be too high.(4)The net photosynthetic rate of panicle leaves showed that with the increase of density,the net photosynthetic rate of spinning stage,grouting stage and mature stage gradually decreased.The net photosynthetic rate of various varieties was Zheng Dan 958>De Mei Ya 3>Ji Dan 27>Xian Yu 335.The net photosynthetic rate of each period,the size of the spinning stage>the grouting stage,>the mature stage.