Abstract: 【Objective】The composition type and amount of HMW-GS effect size of glutenin particle and thus flour quality. They are the important traits of wheat quality which reflect strengths and weaknesses of wheat flour. Three wheat cultivars with different Genotypes were selected to study the effects of water-nitrogen interaction on relative content of each HMW-GS、contents of total HMW-GS and GMP size distribution.【Method】Content of HMW-GS and GMP size distribution in wheat grain were quantified by RP-HPLC and laser granularity analysis instrument, respectively.【Result】Irrigation conditions, it is to the benefit of HMW-GS, LMW-GS of GMP accumulation and increasing large particle size distribution of particles of wheat GC8901, medium wheat TS23 by increasing nitrogen fertilizer rate, and thus also the corresponding GMP content increased, while HMW-GS, LMW-GS accumulation of the weak wheat SN1391 has been inhibited, but conducive to the formation of large size particles in GMP. Compared with the irrigation conditions, appropriately, dry conditions (no irrigation), increasing N is conducive to HMW-GS, LMW-GS content of SN1391 grains increased, while the proportion of large size particles in GMP have been significantly improved.【Conclusion】Interaction between irrigation and increasing nitrogen application has positive effect on the GC8901 and TS23, while the drought and increasing nitrogen has a positive effect on SN1391.

Key words:  Wheat, Water-nitrogen interaction, high molecular weight glutenin subunits(HMW-GS), glutenin macropolymer(GMP), Distribution of particle size