Effects Of Combined Application Of Controlled Release Nitrogen Fertilizers On Physiological Characteristics And Yield Of Double-season Rice

In order to further improve the double-season rice cultivation technology and provide a theoretical basis for the production of double-season rice in Hunan.The purpose of this study was to investigate the effects of different controlled-release nitrogen fertilizer application modes on tillering characteristics,dry matter accumulation,physiological function,yield and yield components of the double-season rice,and to study its mechanism.The experiment was carried out at the Hunan University Agricultural University’s Liuyang Farm Internship Base in 2018.The design of the split area was used to set up 6 kinds of early rice,Lu Liangyou 996,Zhong Jiazao 17,Late Rice H you 518 and Xiang Wanxian 17.Fertilization mode: no nitrogen fertilizer for control,conventional urea,controlled release nitrogen fertilizer and conventional urea 5:5,controlled release nitrogen fertilizer and urea weight loss 30%,controlled release nitrogen fertilizer and urea weight loss 30% with organic fertilizer,controlled release nitrogen fertilizer and urea each weight loss 30% with biochar.In order to clarify the effects of six fertilization modes on rice growth and development,physiological characteristics and yield,the main results are as follows:1.In the study of the physiological effects of different fertilization modes on double-season rice,30% of the controlled release nitrogen fertilizer and urea weight loss combined with organic fertilizer model can significantly increase the tillering rate of rice,compete for the number of seedlings with high yield,and enhance the CAT activity of late leaves.Improve leaf chlorophyll content;controlled release nitrogen fertilizer and urea weight loss 30% with biochar can significantly accelerate rice tillering rate and reduce MDA content in late growth stage.2.Different fertilization modes have significant or extremely significant regulatory effects on the dry matter accumulation of rice in the main growth period.Compared with conventional urea treatment,controlled release nitrogen fertilizer and urea are 30% different in weight,combined with organic fertilizer,controlled release nitrogen fertilizer and urea.The 30% weight loss combined with biochar can significantly increase the dry matter accumulation and population growth rate in the late growth stage of rice,and the mode of organic fertilizer application with controlled release nitrogen fertilizer and urea weight loss of 30% is most significant.3.In the study of the yield and yield components of double-season rice in different fertilization modes,the controlled release nitrogen fertilizer and urea 5:5 mode can significantly increase the effective panicle number and 1000-grain weight during rice maturity;the controlled release nitrogen fertilizer and urea weight loss 30 The organic fertilizer combined with organic fertilizer can effectively increase the number of effective panicles,grain per spike and 1000-grain weight of rice,which is 5.5%-12.84% higher than that of conventional urea treatment;30% of controlled release nitrogen fertilizer and urea can effectively increase biochar.The number of effective panicles,seed setting rate,and 1000-grain weight of rice increased.According to the effect of different controlled-release nitrogen fertilizer application modes on the yield and yield of double-season rice,30% of controlled-release nitrogen fertilizer and urea were combined with organic fertilizer to increase yield,and the yield increase was relatively stable.