Effects of Nitrogen Application on Yield,Quality and Fertilizer Efficiency of Ja-ponica Rice in Northern China
The effects of nitrogen application on yield,quality and nitrogen fertilizer use efficiency of Longdao 18 and Suijing 18 varieties were studied through field experiments for two years.The results showed that the main rea-son for increasing rice production was the increase of effective panicle number and grain number per panicle.In each fertilization treatment,when nitrogen application was reduced by 15％compared with the applying amount of target yield,there was no significant difference in the yield and yield components of Longdao 18 and Suijing 18 vari-eties in 2022 and 2023,and the nitrogen utilization rate increased by 4.52％and 5.51％respectively.However,when controlled release urea was mixed with ordinary urea,the panicle number of Longdao 18 and Suijing 18 in-creased by 19.8 panicle and 20.9 panicle per square meters on average,and the panicle number decreased by 8.3 panicle and 6.2 panicle per ear on average.The difference in nitrogen utilization rate was not significant,but this method of nitrogen application reduced the topdressing twice and saved labor.Nitrogen application significantly in-creased the roughness and milled rice ratio of Longdao 18,but had no significant effect on Suijing 18.Application of nitrogen fertilizer had little effect on amylose content of the two varieties,but significantly increased protein content and decreased chalky grain rate,chalkiness degree and food taste score.Under the condition of same nitrogen appli-cation rate,controlled release urea and common urea mixed one times application than application ordinary urea fer-tilizer in stages significantly improved the rice appearance quality,chalky rice percentage and chalk rice whiteness rate by an average of 1.59％and 0.66％respectively of Longdao 18,chalky rice percentage and chalk white rate by an average of 0.31％and 0.13％respectively of suijiang18,and other various nitrogen treatment processing quality,nutritional quality,and no significant difference between eating quality.
RiceYieldQualityNitrogen fertilizer use efficiency
NETL
NSTL
万方数据
