Effect Of Nitrogen And Irrigation On Grain Yield And Processing Quality Of Different Wheat Genotypes

In order to explore the influence of irrigation stage and proportion,nitrogen fertilization rates and proportion on the grain yield and its components, milling quality and processing quality of tow wheat genotypes, and provide theoretical basis and technical support for water-saving and high-output cultivation of winter-wheat. The experiment was carried out at the experimental station of the Institute of Crop Sciences, Chinese Academy of Agricultural Sciences (Beijing) form September 2009 to June 2010.The main objective was to study the influence of nitrogen (N) and irrigation on the yield, quality and physiological parameters in tow wheat genotypes.The main findings are as follows:1. Effects of nitrogen fertilization rates on Grain Yield and Processing Quality of different wheat genotypesWithin the range of 0~360 kg·hm-2 fertilizer levels, increased the amount of N-fertilizer, could suppress chlorophyll's degrading, keep the N-content of flag at high level, eased flag leaf senescence, prolong the functional stage of flag. strong gluten wheat JM20 and WM38 chlorophyll's content and N content of flag leaf decreased slowly than middle gluten wheat JD8 and ZM8. The grain yield and protein yield all increased with the amount of N-fertilizer added, have maximum under the treatment of applying nitrogen at N 270 kg·hm-2 ,When the nitrogen application rate increased to 360kg·hm-2 , Strong gluten wheat grain yield and protein yield are higher than medium gluten wheat.The nitrogen treatment could increase flour yield, rigidity, protein content and sedimentation volume.The nitrogen treatment 180kg·hm-2 prolonged the development time and stability time, decreased the water absorption, the score of bread is highest. strong gluten wheat hardness, protein content, flour yield and sedimentation value is high, the dough development time and stability for a long time, bread bulky, score high.2. Effects of nitrogen fertilization application time on Grain Yield and Processing Quality of different wheat genotypesThe total amount of nitrogen in the 270 kg·hm-2 under the conditions,different nitrogen fortification application time,the amount of N-fertilizer were decreased with flag leaf start time delays ,Start from the flag leaf to 14 days,nitrogen fertilization application on 2nd spring-leaf and 5th spring-leaf N content of flag leaf were significantly higher than that of flowering fertilizer,Late effects on fertility were not significant, however,significant differences between varieties.The grains per spike of treatment of topdressing at 2nd spring-leaf significantly more than others.The 1000-grain weight is expressed as fertilizer flowering stage was significantly higher than other treatments.Spike of strong gluten wheat was significantly higher than middle gluten wheat ,the grains per spike followed by a more to less was zhongmai8, wanmai38, jimai20, jingdong8.The higher the sedimentation volume of dealing with top-dressing the earlier , the lowestthe sedimentation volume is flowering fertilizer.With the advance of Nitrogen water absorption was decreased.The water absorption of wanmai38 and jingdong8 was significantly higher than jimai20 and zhongmai8. The stability time, bread volume, bread score of jimai20 top-dressing in 5th spring-leaf was significantly higher than others.The stability time, bread volume, bread score from long to short, decreasing order was jimai20>wanmai38>jingdong8>zhongmai8, have a significant difference.3. Effects of Irrigation Stage and Proportion on Grain Yield and Processing Quality in Different Wheat VarietiesThe irrigation ratio of 1:3 treatment ( B1 indicate irrigating 300m3·hm-2 at emergence of 2nd spring-leaf + irrigating 900 m3·hm-2 at emergence of 5th spring-leaf )and 3:1 treatment (B4 indicate irrigating 900m3·hm-2 at emergence of 5th spring-leaf + irrigating 300m3·hm-2 at emergence of flowering) were propitious to reduce proline content in flag leaf and mitigate total nitrogen losing of flag leaf, prolong the functional stage of flag leaf .Proline content and total nitrogen content of flag leaf have no significant difference between "jimai 20" and "zhongmai 8". The irrigation ratio of 1:3 and 3:1treatments increased spike number and protein content,the irrigation ratio of 1:1treatments(B2 indicate irrigating 600m3·hm-2 at emergence of 2nd spring-leaf + irrigating600m3·hm-2 at emergence of 5th spring-leaf and B3 indicate irrigating 600m3·hm-2 at emergence of 5th spring-leaf +irrigating 600m3·hm-2 at emergence of flowering)increased the number of grain per spike. The grains per spike and 1000-grain weight of treatment B3 were highest;the ears, grain yield and protein content of treatment B4 were highest. The value of ears, grains per spike,1000-grain weight, grain yield of "zhongmai 8" were higher than those of "jimai 20"in all the irrigation treatments,but the protein content was significantly lower than "jimai20" . Treatment B2 and B4 increased the sedimentation volume and wet gluten content, prolonged the stability time. Irrigation at emergence of 2nd spring-leaf+ 5th spring-leaf(B1,B2)were prolonged the development time, improved the processing quality of wheat.