Studies On Mechanism Of Quality Development In Different Types Of Winter Wheat

It studied how the varieties responded to the N fertilizer rates and thedressing stage so as to inquire into the theory that the difference existed in thewheat quality. It applied four varieties just as Jinan17 PH82-2-2 PH97-4 andPH97-5 in which the difference of quality was significantly. In the condition ofN fertilizer rates (high and low) and the dressing stage (the jointing stage andthe heading stage), In case, the experiment be launched in farm and theanalysis of physiology and biochemistry be launched indoors, it was inprogress in Shandong agriculture university. It indicated the case as: 1.The responses of grain yield and quality of different winter wheatvarieties to nitrogen were studied on the condition of two N rates (88kg·hm-2and 176kg·hm-2, pure nitrogen) and two top dressing stages (rising stage andheading stage). The results indicated grain yield and N harvest weresignificantly higher at high N rate than at low N rate, increasing by401.9kg·hm-2 and 11.9kg·hm-2 respectively; and they were more when Nfertilizer was applied at rising stage than it was at heading stage, increasing by379.3kg hm-2 and 8.1kg hm-2 respectively. Response of protein content ofdifferent varieties was different at two N fertilizer rates and two top dressingstages. Difference of protein content of between Jinan17 and PH97-4 was notsignificant at different N rates, however, protein content of PH82-2-2 andPH97-5 were significantly higher when N fertilizer was applied at headingstage than it was at rising stage, up 0.6 per cent. Differences of wet glutencontent and volume weight and hardness of grain were not significant atdifferent N rates, and they were higher when N fertilizer was applied atheading stage. Differences of sedimentation volume and falling number werenot significant at different N rates and at top dressing stages. Water absorptionand stability time of paste were not distinct at different N rates, and waterabsorption of flour increased by 0.7 per cent, while developing time andstability time of paste decreased respectively by 1.39min and 0.61min when N 3不同类型冬小麦品质形成差异机理的研究fertilizer was applied at heading stage. Flour quality parameters of differentwinter wheat varieties were markedly diverse. Processing quality couldimprove if we properly applied N fertilizer, however, the effect was notdistinct. Quality characteristics of winter wheat varieties were dominated bygenotypes. 2.The accumulation and distribution of nitrogen were significant differentin different varieties. The kernel nitrogen accumulation of high-proteinvarieties (PH82-2-2 and PH97-5) was high in maturity. Nitrogen accumulationwas much more in stem and vagina and less in leaf of PH97-4. The dressingtime and nitrogen apply amount had less effect on nitrogen accumulation inkernel. 3.The time of dressing fertilizer had significant effect on nitrogenutilization rate in season. Compared with dressing at heading stage, the ratecould be increased by 10% as dressing at jointing stage. The significantdifferences of nitrogen utilization rate in varieties were due to the generaldistributed differences of absorbing nitrogen in varieties. 4.The dynamic changes of free amino acids were significantly different invarieties. The content of free amino acids of PH82-2-2 was highest before 21DAA and that of PH97-5 declined slowly after 21 DAA. The content of thetwo varieties came to be comparatively high in the end. The dynamic changesof protein content were significantly different in varieties. The protein contentwas higher in PH82-2-2 from first to last and that of PH97-4 was the lowest.The protein accumulation of PH97-5 speed up after 21 DAA, then went to ahigh level. The nitrogen supply amount had no significant effect on thedynamic content changes of free amino acids and protein. The dressing timehad effect on the changes of free amino acids content, but it had no significanteffec...