Responses Of Different Maize Genotypes To Nitrogen Fertilizer And Density

Nitrogen is the mineral nutrient element necessary for the growth and development of corn.It is also the most important fertilizer factor in agricultural production.It is essential for corn yield and quality.Under high-yield and intensive production conditions,increasing planting density and increasing nitrogen use efficiency are the continuous increase of maize yield.The main measures,therefore,screening and evaluation of high-yield,high-yield and high-yielding maize hybrids,and constantly tapping their biological potential,is one of the important ways to achieve fertilizer production and efficiency.In this study,split plot experiment was conducted on 24 maize hybrids under the conditions of three nitrogen levels of 0,120,240 N kg/ha,high density(80000 plants/ha)and low density(60000 plants/ha).The nitrogen efficiency and density tolerance were evaluated,and the responses of agronomic traits such as yield and related traits,nitrogen efficiency,root configuration and leaf angle to nitrogen and density were compared and analyzed.The main results are as follows:1.Screened out high-yield nitrogen-tolerant maize hybrids: Jinqing 202,Xianyu 335,Dika 517 and other 6 maize hybrids;double inefficient maize hybrids: Jinhai 5,Deyu 919,Yanke 288 and other 5 maize hybrids,of which high-yield nitrogen-resistant varieties Has a large yield and nitrogen saving potential.The planting density was increased under low nitrogen conditions,and the nitrogen uptake and nitrogen uptake efficiency of the high-capacity nitrogen-sensitive varieties increased significantly.2.Under the condition of N0 and N120,the root-configuration traits of high-density nitrogen-resistant type after increased the planting density,the root opening angle,root projection area,maximum root width,and total root length decreased significantly After increasing the density.Nitrogen double inefficient type,the root opening angle and the maximum root width are lower than the maximum root width under N120 conditions,the difference is not significant3.Under the condition of low nitrogen,the high-yield and high-yield maize hybrids had larger leaf angles.Under the condition of increasing nitrogen supply,the angle of the leaves decreased.The angle of the leaves in the upper part of the nitrogen double-inefficient type is small,under the condition of increasing nitrogen supply,the angle of the leaves is unchanged.4.The coefficient of variation between single ear and row was significantly negatively correlated with yield,and the coefficient of variation between rows with high density and high nitrogen tolerance was lower than other types.5.Increasing planting density under low nitrogen conditions resulted in a significant increase in yield due to a significant increase in the number of panicles per unit area by 26.8% and a significant increase in nitrogen uptake by 52.7%,while there was no significant change in single ear weight.