关键词: 优质稻, 施氮量, 产量, 品质, 江汉平原

Abstract: Six typical long⁃grain high⁃quality indica rice varieties（Ezhong 5，Jianzhen 2，Taiyouexiangsimiao，Taoyouxiangzhan，Xiangyaxiangzhan，Yexiangyoulisi）were selected to study the yield and its component and processing，appearance，cooking，nutritional qualities under different nitrogen application rates［105 kg/ha（N1），135 kg/ha（N2），165 kg/ha（N3），195 kg/ha（N4）and 225 kg/ha（N5）］，and the reasonable nitrogen application rate for high yield and quality of rice was explored，so as to provide a theoretical basis for the promotion of high⁃yield cultivation technology of high⁃quality rice. The results showed that the yield of rice increased first and then decreased with the increase of nitrogen application rate，the yields of N2 and N3 were generally higher，and there was no significant difference between them. Ezhong 5，Taiyouexiangsimiao and Taoyouxiangzhan had the highest yield under N3 treatment，which were 7.4，10.3，10.0 t/ha；Jianzhen 2，Xiangyaxiangzhan and Yexiangyoulisi had the highest yield under N2 treatment，which were 9.0，8.3，10.3 t/ha.The main reason for the increase of yield was the increase in the effective panicle number and seed setting rate. The yield order was Taoyouxiangzhan>Taiyouexiangsimiao>Yexiangyoulisi>Jianzhen 2>Xiangyaxiangzhan>Ezhong 5. In terms of quality，except for Yexiangyoulisi，the rice processing quality of the remaining varieties had a consistent response to the nitrogen application rate. N2 and N3 treatments generally had higher brown rice rate，polished rice rat and whole polished rice rate；for chalkiness degree and chalkiness rate，Jianzhen 2，Taiyouexiangsimiao and Xiangyaxiangzhan were the lowest under N3 treatment，Taoyouxiangzhan and Yexiangyoulisi were the lowest under N2 treatment. The order of chalkiness degree and chalkiness rate was Taiyouexiangsimiao>Jianzhen2>Taoyouxiangzhan>Xiangyaxiangzhan and Yexiangyoulisi>Ezhong 5. For the amylose content，Yexiangyoulisi had the lowest value under N2 treatment Xiangyaxiangzhan had the lowest value underN4 treatment，the other four varieties had the lowest value under N3 treatment. In terms of the characteristics of starch RVA spectrum，Ezhong 5 and Taiyouexiangsimiao had the highest breakdown viscosity and lowest setback value under N3 treatment， Jianzhen2， Taoyouxiangzhan and Xiangyaxiangzhan had the highest breakdown viscosity and lowest setback value under N1 treatment，and Yexiangyoulisi had the highest breakdown viscosity and lowest setback value under N2 treatment.In terms of the crude protein content and its components contents of polished rice，Ezhong 5 and Taoyouxiangzhan had lower crude protein content of 4.5%—5.9%，the other four varieties had higher crude protein content of 10.4%—15.4%.The albumin content of most varieties was the highest under N5 treatment；the gliadin content of most varieties was the highest under N4 treatment；the contents of globulin and gluten increased first and then decreased with the increase of nitrogen application rate，and N3 treatment was the highest for most varieties.On the whole，the optimal nitrogen application rate suitable for high⁃quality rice production was 135—165 kg/ha in the Jianghan Plain area.

Key words: High?quality rice, Nitrogen application rate, Yield, Quality, Jianghan Plain