| The field experiment was carried out in the south part of loess plateau with 632mm precipitation each year. Eight winter wheat (NR9405, 9430,Yanshi 9, XiaoyanNo.6, Shan229, Xinong2208, Aifeng 3 and Sangl 88) were used as indicating crops to study the grain filling characters and matter translocation efficiencies on two nitrogen application rate(0,90kgN/hm2) . The results showed as following:1. Physiological parameters, such as photosynthetic rate(Pn), stomatal conductance, transpiration rate(E), short time water use efficiency(WUE), SPAD and senescence index were effected mainly by the genotype. Nitrogen fertilizer mainly affected the winter wheat individual character and colony's structure ,nitrogen had less affected on functional leaves than genetic factors.2. The genetic difference was the main factor that affected grain filling characteristic parameter and the nitrogen fertilizer's effect was less than genotype. The effect of nitrogen on the such parameters had relations with genotype, on the other hand, the effect on different parameters were different to different genotype. There were significant difference of genotypes on the mean nitrogen uptaking rate during active grain nitrogen uptaking period(NURmeanD) was different among genotypes. During of maximum grain filling rate(GFRmaxD), active grain filling period (from 10%-90% of grain weight)(D), active grain nitrogen uptaking period (from 10%-90% of grain accumulated nitrogenXDN) on different genotype wheat. GFRmaxD, GFRmaxGD,D, DN, which were main factor on grain weight had significant positive relation with 1000 kernel weight.3. The difference on grain volume and harvest index during grain filling process was mainly affected by gene, especially the kernel volume and dHI/dt were the inherent character of genotype, which weren't affected by nitrogen application rate, the grain water contents were decreased lineally during grain filling period, grain fresh weight increased as quadratic. XiaoyanNo.6 had 9 days of linear phase during the grain maximum volume, but Sangl 88 and 9430 decreased quickly when they reached the maximum volume point, which showed apparent quadratic .4. During grain filling period, the grain's nitrogen content changed as "high- low- high". XiaoyanNo.6 nitrogen concentration was always higher than that of Sangl 88 and 9430, but XiaoyanNo.6 and Sangl 88 and 9430 grain phosphorus concentration declined linearly. In some extent, the application of nitrogen fertilizer could increase grain nitrogen concentration during grain filling period, the grain final nitrogen concentration was coincident with nitrogen concentration during grain filling. Increasing nitrogen uptaking rate and phase could be useful for grain protein concentration .5.Winter wheat dry matter production and matter translocation efficiencies were affected by genotype and nitrogen fertilizer. There were no significant differences of genotypes on the dry matter of green leaf, spike and stem at anthesis and leaves ,hull,rachis at maturity, but significant differences on old leaf.stems at anthesis and stems.grain at maturity were detected. Nitrogen application rate couldsignificant increased wheat dry matter production at anthesis and maturity. Among eight genotype.for the dry matter translocation(DMT) ,dry matter translocation efficiencies(DMTE) and .proportion of dry matter translocation for grain(DMTP) ,the highest and the lowest was NR9405 and YanshiNo.9 respectively .Both genotype and nitrogen application were correlated with the DMT.DMTE and DMTP.There were no significant differences of genotypes and nitrogen application on the nitrogen translocation(NT) .nitrogen translocation efficiency(NTE), contribution transfer nitrogen to grain(PCR) and nitrogen harvest index(NHI).NR9405 was highest in NTE which was 76.65% and Shan 229 was lowest which was 66.82% .Nitrogen harvest index decreased in the order of Shan229>9403>Aifeng3>Xinoncp208>Yansih9>188>NR9405>Xianyan6. There was significant positive correlation between NTE and DTE .Stems and leaves dry...
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