The Effect Of Density On The Yield And Agronomic Traits Of Summer Maize Varieties In The Irrigated Area Of ??eastern Weinan

In order to make full use of the advantages of summer maize varieties and cultivation techniques to improve the yield in the eastern Weinan irrigation area,the density allocation experiment of different types of maize varieties was carried out.The experiment was conducted in June 2018 in Huazhou District,Weinan City,Guanzhong East,Shaanxi Province.In the experiment,the early-maturing varieties Shandan 636 and Shandan 650,the middle-maturing varieties Shandan 609 and Zhengdan 958,the late-maturing varieties Shandan 8806 and Dongdan 60 were selected to sown under 45,000 plants/hm~2,60000plants/hm~2,75000 plants/hm~2 and 90,000 plants/hm~2.The yield and main agronomic traits were measured.The agronomic traits and ear traits were analyzed.These main results are as follows:1?The yield increased and then decreased with the increase of density.Among them,the yield of early-maturing varieties increased gradually with the increase of density,and the yield of mid-late mature varieties increased first and then decreased with the increase of density.The high-yield suitable density suitable for planting in the eastern Weinan irrigation area is:the suitable density of early-maturing varieties is not less than 75000plants/hm~2,and the suitable density of mid-late-maturing varieties is not more than 75000plants/hm~2.2?With the density changes,the agronomic traits of summer maize change differently.The variation of plant height increased with the growth period,and the performance of late-maturing varieties was more obvious.The height of ear height increased with the increase of density,and the effect of density on ear height of early-maturing varieties was higher.The late-maturing varieties were larger;the empty stalk rate and the double-earing rate increased with the increasein density.3?There are large differences in the laws governing the economic traits of the panicles.With the change of density,there was no significant effect on the number of spikes in late-maturing summer maize varieties,and the number of spikes in early-maturing and mid-maturing summer maize varieties was significant.Different densities had no significant effect on ear length of early maturing and mid-maturing summer maize varieties,but had significant effects on ear length of late maturing summer maize varieties,which showed that the ear length decreased significantly with increasing density.The density had a significant effect on the grain number of late-maturing summer maize varieties,and decreaseed with the increase of density.When the density exceeds 75,000 plants/hm~2,the density was greatly reduced.Different densities had significant effects on the grain water content of medium-maturing varieties,and showed a significant increase with increasing density.4?The density of early maturing summer maize in the eastern part of Weinan was not less than 75000 plants/hm~2,the suitable density of mid-maturing summer maize varieties was 75000 plants/hm~2,and the density of late-maturing summer maize varieties should not exceed 60,000 plants/hm~2.According to the type of growth period,the summer and summer maize varieties Shandan 650 and Shandan 636 had the characteristics of short growth period,dense planting,low grain water content and high yield during harvesting.It was more suitable for the direct harvesting of grain in the eastern Weinan irrigation area to raise the masses and econimc benifits.