Sensitivity of wheat grain quality to nitrogen application in middle and lower reaches of Yangtze River

Objective Sensitivity of quality traits of wheat cultivars to nitrogen application in middle and lower reaches of Yangtze River wheat planting region was analyzed to provide reference for the production of weak gluten wheat and high quality breeding.Method Field trials on 105 wheat cultivars collected from middle and lower reaches of Yangtze River wheat planting region were carried out with low nitrogen(120 kg/ha pure nitrogen)and high nitrogen(280 kg/ha pure nitrogen) treatments to measure the related traits of wheat grain quality of different wheat cultivars.In addition,the sensitivity of 105 cultivars to nitrogen fertilizer was analyzed in accordance to grain protein contents.ResultThere were significant differences (P<0.01,the same below) in wheat grain quality traits among cultivars and nitrogen application amounts in middle and lower reaches of Yangtze River wheat planting region.And the quality traits contained high genetic diversity.Under high nitrogen treatment,protein content,wet gluten content and dough stability time were significantly increased,and sedimentation value,1000-grain weight and grain hardness were also increased.Correlation analysis for different quality traits revealed that grain protein content was significantly positively correlated to wet gluten content and dough stability time,and the correlation coefficient was larger than 0.5000.According to the sensitivity of the grain quality traits to nitrogen,all the cultivars in this region could be classified into three groups,namely nitrogen-sensitive genotype (34),nitrogen-insensitive genotype (25) and intermediate genotype (46).Effect analysis on grain protein content under different nitrogen application rates of 15 weak-gluten wheat cultivars used in production showed that all these cultivars could reach the national standard of GB/T 17893-1999 High Quality Wheat-Weak Gluten Wheat under low nitrogen treatment.Protein contents of Ningmai 9 and Yangrnai 15 were stable under different nitrogen application rates,while Ningmai 13,Emai 520,Yangmai 9 and Ningmai 20 were more sensitive to different nitrogen application rates.Conclusion The application rates of nitrogen fertilizer should be controlled in field to balance quality and output based on sensitivity variation of grain quality of different wheat cultivars to nitrogen.