Effects Of Cultivar And Planting Density On Grain Yield Of Maize In Weinan

Maize is the second largest crop in Shaanxi Province.In recent years,the planting area has remained at about 1 million hm².But the yield per unit area is relatively low.The reason for this is related not only to the influence of natural factors,but also to the lack of integrated varieties and low integration of cultivation techniques.Variety,sowing date,density and region are the main influence factors of high yield and high quality cultivation techniques.Increasing planting date and density is the main measure to increase maize yield.Rational increasing planting density,sowing date,variety and cultivation measures suitable for the local ecological environment are main measures for high yields.In this study,in recent years,the large-area planting or newly approved maize varieties were used as experimental materials to conduct comparison tests on planting density,sowing date,variety,and location,and to analyze the yield and yield components of each variety,aiming at providing the basis for maize varieties selection,suitable sowing date,planting density and its appropriate area in Weinan City.In this study,five new maize varieties widely planted in Weinan were selected.Four pilot sites,Baishui,Dali,Chengcheng and Linwei,were selected to analyze the effects of different cultivar and different densities on maize yield and yield components.The main conclusions are as follows:?1?Maize growth period is closely related to sowing date.The effects of different treatment conditions on the 100-grain weight of maize were obvious,Xianyu 335,Zhengdan958,and Shandan 618 performed relatively well,and their D1(6.75×104·hm^-2)treatment was better than D2(8.25×104·hm^-2).The sowing date ahead of schedule significantly increased the yield of maize,and the variation coefficient of spring sowing was less than summer sowing.The yield was Baishui County>Chengcheng County>Dali County>Linwei District.The Baishui and Chengcheng County pilots which were spring sowing show high yields,but they are subject to large changes in different density.?2?The analysis of different yields showed that with the increase of yield per unit area,the number of grains per spike and 100-grain weight of spring sown maize increased continuously,while that of summer sowing showed that the 100-grain weight decreased and the number of grains per spike increased.With the increase of the yield per unit area,the correlation between the number of grains per spike,the 100-grain weight and yield in spring sown maize is more obvious,but the performance in summer sowing maize is not obvious.?3?Xianyu 335,Shandan 618,and Zhengdan 958 maize varieties performed well.Shandan 622 showed high yield in Dali County and Linwei District.?4?A cultivating maize mulching technique demonstration area of 4000 hm² was established in Chengcheng County,Weinan City.A maize variety of Zhengdan 958 was selected,six key technologies were adopted that excellent varieties,mulching,soil testing fertilizer application,wide and narrow row sowing,reasonable close planting,and prevention and control of pests and weeds without pollution.The demonstration area has achieved high yield records of 9459 kg/hm²,which is higher than the average yield of maize by 3222 kg/hm²,and the increase rate is 51.6%.The increase in production efficiency is significant.Therefore,according to the characteristics of species and the local ecological environment,suitable planting time and density should be selected for reasonable planting.It is very important to promote maize which can resistance to close planting and can be widely planted,and at the same time achieving high and stable yields based on the appropriate sowing time and area.