Effect of interactions between water management and nitrogen fertilizer on wheat processing quality and their relationship with protein fractions.

This study was carried out at the Experiment Station of Shandong Agricultural University,under a rain-proof through shelter.A winter wheat cultivar Jimai 20 with high grain yield and strong gluten was selected in this study.The objective of this study was to determine the effects of irrigation rate and nitrogen fertilizer rate on wheat processing quality and their relationship to protein fractions.The results were as follows.When the nitrogen rate increased from 120 kg·ha to 240 kg·ha,grain protein content,albumin content,and globulin content increased;while the ratio of gliadin glutenin content to albumin globulin content decreased,which induced the decrease of the dough stability time.Under the same nitrogen rate,when the irrigation rate changed from W0(no irrigation) to W1(twice irrigation,before planting and at jointing stage),grain protein content increased,but the ratio of gliadin glutenin content to albumin globulin content decreased,and the dough stability time decreased as well;when irrigation rate changed from W1 to W2(three times irrigation,before planting,at jointing stage,and at anthesis stage) and W3(five times irrigation,before planting,before winter,at jointing stage,and at anthesis stage and during grain filling),grain protein content decreased,and gliadin glutenin content decreased as well,but albumin globulin content increased,and at last,the ratio of gliadin glutenin content to albumin globulin content decreased and the dough stability time decreased.The above results indicated that,under the condition of this experiment,the increase of irrigation induced the decrease of dough stability time,due to the decrease of gliadin glutenin content,and the decrease of the ratio of gliadin glutenin content to albumin globulin content.