Responses Of Grain Yield,Quality And Rice Flour Processing Characteristics Of Early Indica Rice To Nitrogen Application

Double cropping early indica rice is the main raw material for processing rice flour.It is of great significance to carry out the screening of rice flour and its high yield technology.In this study,early indica rice varieties Lingliangyou 722,Jiayu 253,Zhongzao 39,Zhuliangyou 171,Zhongjiazao 17,Jinzao 47 and Tanliangyou 83 in double cropping rice area were used as research materials to compare the yield,quality and rice flour processing characteristics of different early indica rice varieties,The aim of this study was to screen out high-yield double-cropping early indica rice varieties suitable for processing.The selected rice flour rice varieties and the control variety Jiangzaoyouzhan were used to carry out nitrogen fertilizer management experiments from 2021 to 2022.Four different nitrogen management treatments were set up with the ratio of base fertilizer:tillering fertilizer:panicle fertilizer of 5:5:0,5:4:1,5:2:3 and 5:0:5,to clarify the nitrogen fertilizer management strategy under the optimization of yield,quality and rice flour processing characteristics of early indica rice.The main results are as follows:1.The variety comparison test showed that Zhongjiazao 17 not only had a high yield of 7.8 t hm^-2,which was 7%～51%higher than that of other varieties,but also had high brown rice rate,milled rice rate and head milled rice rate,amylose content of25.03%,high breakdown,low setback,excellent RVA,low broken rate and cooking loss rate of rice flour,good cooking characteristics of rice flour,moderate elasticity and chewiness,and good texture characteristics of rice flour.So Zhongjiazao 17 is a double cropping early indica rice variety suitable for rice flour.2.Nitrogen management experiments showed that the effects of different nitrogen management on the yield and quality of rice flour rice Zhongjiazao 17 and non-rice flour rice Jiangzaoyouzhan were basically the same.With the increase of panicle fertilizer ratio,the effective panicle number and grain number per panicle of the two varieties increased,and the yield was the highest under 5:2:3treatment.The head milled rice rate of Zhongjiazao 17 and Jiangzaoyouzhan increased,but the chalky grain rate and chalkiness degree of Zhongjiazao 17 increased,while the chalky grain rate and chalkiness degree of Jiangzaoyouzhan decreased.The amylose content of the two varieties decreased,the gel consistency,protein content and the breakdown increased,the setback decreased,and the RVA spectrum characteristics became better.In terms of rice flour processing characteristics,the broken flour rate and cooking loss rate of Zhongjiazao 17 under 5:2:3 treatment were the lowest,while Jiangzaoyouzhan accounted for the highest;hardness and chewiness were the lowest,and viscosity was the highest.In summary,Zhongjiazao 17 is an early indica rice variety suitable for rice flour rice.And under the condition of base fertilizer:tiller fertilizer:panicle fertilizer ratio of 5:2:3,not only the yield is high,but also the cooking characteristics of rice flour are good.