| The physiological basis of the effect of phosphorus on kernel yield and quality in wheat was studied using two different winter wheat cultivars, Lumai 22, which has 9000kg/hm2 yield potential and medium gluten potential, and Jinan 17, which has 7500kg/hm2 yield potential and strong gluten potential. The experimentation was carried out at the experimental farm of shandong agricultural university , and Erhu village, Jiaoyu Town of Taian city from 2001to 2002 using the method of field culture combined with pot culture. The main results as follows:1. The difference of yield and quality formation between two wheat cultivars1.1 The difference of carbon and nitrogen metabolism in flag leaf between two wheat cultivars Lumai 22 showed a higher carbon metabolism level in flag leaf than that in Jinan 17. Compared with Jinan 17, the content of chlorophyll, the photosynthesis rate and the sucrose synthesis ability were higher, the peak period of photosynthesis rate was longer in flag leaf after anthesis in Lumai 22, thus the source organs of Lumai 22 had higher producing photosynthesis ability than that of Jinan 17.Jinan 17 showed a higher nitrogen metabolism in flag leaf than that in Lumai 22. Compared with Lumai 22, the activities of nitrogen assimilation key enzymes NR and GS in flag leaf were higher after anthesis in Jinan 17, the EP activity in flag leaf which has a important role in protein degradation was higher after anthesis, the accumulation amount of free amino acid during the early kernel filling period, and the transport amount of free amino acid from flag leaf to kernel during the kernel filling period were much more in Jinan 17, thus provided more substrates for protein synthesis in kernel.1.2 The difference of starch and protein synthesis in kernel between two wheat cultivarsThe amylose content in Jinan 17 was higher that in Lumai 22 during kernel filling, but the amylopectin and total starch contents had no significance differences between the two wheat cultivars. The starch accumulation rate declined earlier in Jinan 17 than that in Lumai 22, and the starch accumulation rate was lower in Jinan 17 than that in Lumai 22 after 21 DAA, this were the reasons why the kernel weight was much lower in Jinan 17 than that in Lumai 22.The changes of protein content and its components contents was same in the two wheat cultivars, but the globulin content, the gliadin content and the GMP content were higher in Jinan 17 than that in Lumai 22 during kernel filling period, and the total protein content in Jinan 17 was significant higher than that in Lumai 22 in maturity. 1.3 The difference of yield and quality index between the two wheat cultivarsThe spike number per hectare in Lumai 22 was lower than that in Jinan 17, but the kernel number per spike, the kernel weight, the kernel yield and biology yield, the harvesting index were higher in Lumai 22 than those in Jinan 17.Compared with Lumai 22, the protein content, the SDS sedimentation volume, and the wet gluten content were significantly higher in Jinan 17, so those reflected on the farinogran index, i.e. Jinan 17 had higher flour water absorption rate, longer dough developing time, longer dough stability time and dough breakdown time.2 Effect of different supplied phosphorus level on yield and quality along with physiologicalbasis in wheat2.1 Effect of different supplied phosphorus level on yield and qualityWith the increasing of supplied phosphorus amount, the spike number per hectare, the kernel number per spike, the weight per 1000 kernels, the biology yield and kernel yield were improved, and among those index, the improving extent of phosphorus to the spike number per hectare was the most, and the P1 treatment gained the highest weight per 1000 kernels.Compared with the control, the P1 treatment significantly improved the SDS sedimentation volume, the wet gluten content and flour water absorption rate in the two wheat cultivars, significantly prolonged the dough developing time and stability time in Lumai 22,...
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