Effect of nitrogen application on high molecular weight glutenin subunit expression and grain quality of winter wheat

A pot experiment was carried out to study High Molecular Weight Glutenin Subunit(HMW-GS) expression,quality and their relationship in different gluten wheat types at different N-levels,using SDS-PAGE technology.Two wheat cultivars,strong gluten wheat Linyou 145 and medium gluten wheat Linyou 2018,were used and five rates of N fertilizer were applied(N 0,0.667, 1.332,1.998 and 2.664 g/pot,respectively),with randomized block design.The results showed that,nitrogen application increased HMW-GS expression,and the effect on medium gluten wheat was greater than on strong gluten wheat.The effect of nitrogen application on HMW-GS expression with protein composition differed among subunit type of high quality wheat.Correlation coefficients between HMW-GS expression with gliadin and glutenin in strong gluten wheat were both at 1% significance levels and the correlation coefficient with glutenin in medium gluten wheat was at 5% level.HMW-GS expression was positively correlated with processing quality characteristics.HMW-GS expression in strong gluten wheat was significantly correlated with wet gluten content,stability time,sedimentation value and evaluation value,while HMW-GS expression in medium gluten wheat was only significantly correlated with sedimentation value.