The Effect Of Uniconzole Waterless-Dressing Seeds On The Quality Development Of Winter Wheat

The effect of different concentration of uniconzole dressing seeds without water on winter wheat quality were studied from 2002 to 2003, The experiment were carried out with three winter wheat cultivars Chuanmai31, Chuanmai107, Chuanmai36 and in four sites Ya,an, Qionglai, Jingyan and Hanyuan, The characteristics of phytohormone , nucleic acid , enzyme , protein metabolism , carbohydrate and nitrogen accumulation and transportation and their relationships to grain quality were studied, The results were as follows:1. Uniconzole treatments increased the endogenous hormones level in wheat kernel.Phytohormones had different contents and different peak time during wheat grain filling. GA and IAA had one peak during kernel filling, the maximum appeared at 20 or 25 days after anthesis, the peak value of ZR content appeared after pollination. Uniconzole treatments increased the content and accumulation of GA on three wheat cultivars during the whole grain filling, IAA contents were increased too, the biggish difference between treatments and control appeared at the beginning and peak time. Uniconzole treatments also improved the level of ZR, the ZR values were higher than control from 5 to 25 days after anthesis, and the accumulation of ZR in single kernel were increased, too. The improvement of GA, IAA, ZR level in filling kernel would be beneficial to the kernel nucleic acid and protein synthesize.2.Uniconzole treatments accelerated the metabolization of nucleic acid in flag leaves and kernels.The content of DNA, RNA in flag leaves declined after anthesis, which meaned the catabolism were the mainstream. The DNA, RNA contents were corresponded with soluble protein contents. Uniconzole treatments increased the contents of DNA, RNA in flag leaves, the biggish difference existed from 0 to 20 days after anthesis.The contents of DNA, RNA and total nucleic acid per milligram had the trend of gradual reduction during the kernel growth, the DNA contents were lower than RNA and decreased more slowly thanRNA, which meaned RNA translated to protein constantly. The accumulation of DNA^ RNA and total nucleic per kernel sharply rose after anthesis, which arrived to maximum at 20 days after anthesis. Uniconzole treatments increased the content of DNA, RNA and total nucleic in three cultivars, DNA content with uniconzole treatments had the biggest difference with control at 5 days after anthesis, but RNA were from 5 to 25 days after anthesis.3. Uniconzole treatments improved the activities of GS, GOGAT\ GOT, GPT in flag leaves and kernels.The activity of GS, GOGAT in flag leaf declined after anthesis, but GS activity keep steady from 10 to 15 days after anthesis, maybe the GS1 activity increased during leaf senescence. Uniconzole treatments increased the activity of GS and GOGAT, GS activity were stronger than control from 10 to 25 days after anthesis, but GOGAT were from 0 to 25 days after anthesis. The improvement of GS, GOGAT in flag leaf would promote the assimilation of NH/and transportation of amino acid to kernel.The activity of GS in kernel showed the higher level at the beginning of filling, which rose after anthesis, the maximum appeared at 15 days after anthesis, then GS activity declined fast. The activity of GOGAT in kernel after anthesis presented a single peak value which appeared at 15 or 20 days after anthesis. Uniconzole treatments improved the activity of GS and GOGAT in kernel, GS activities with uniconzole treatments were stronger distinctly than control from 5 to 15 days after anthesis, but GOGAT were at the peak time. The higher activities of GS and GOGAT in kernel were beneficial to the development of glutamic acid and accelerated the metabolization of amino acid in kernel.The activity of GOT in flag leaves had two peak values after anthesis, but the activity of GPT in flag leaves declined after anthesis, from 0 to 5 days after anthesis which descended fast, from 5 to 15 days after anthesis which ascended a little. Uniconzole treatments increased the activity of GOT and GPT in flag leaves in three wheat cultivars. The difference between uniconzole treatments and control in GOT activities were great from 0 to 30 days after anthesis, but in GPT which were from 5 to 20 days after anthesis. The improvements of GOT, GPT activities would be profitable to promote the translation or use of glutamic acid at the prophase and the development of glutamic acid at the anaphase in flag leaves senescence, which would be beneficial to the transportantion of nitrogen from leaves to kernel.The activity of GOT and GPT in kernel had two peak values after anthesis, which appeared at 15(or 20) and 25(or 30) days after anthesis respectively. The first peak value of GOT but the second peak value of GPT were higher in three varieties. Uniconzole treatments improved the activities of GOT and GPT in kernel, from 5 to 35 days after anthesis the GOT activities with uniconzole treatments were remarkable higher than control, but in GPT the most difference between the treatments and control appeared at the peak time. The improvements of GOT> GPT activities in kernel would accelerate the conversion of amino acids, which would be propitious to the development of alanine> aspartic acid andglutamic acid family, and improved protein content and quality.4. Uniconzole treatments accelerated the carbohydrate > nitrogen accumulation and transportation.Uniconzole treatments increased the soluble sugar content in stems n sheathes and flag leaves, the soluble sugar content in single stem were enhanced, too; at he same time, uniconzole treatments had higher soluble sugar content in kernel from 5 to 15 days after anthesis, which would be beneficial to the synthesize of starch and protein, there were little difference of starch content in kernel at mature between treatments and control in three cultivars and four sites.Uniconzole treatments increased the nitrogen content in stems and leaves at jointing stage remarkably, the nitrogen in different organs were increased at anthesis stage, the ranges were bigger in leaves, the treatments with uniconzole had higher distribution quantum of nitrogen in stems-, leaves-, sheathes -. spikes and roots, so the accumulation per plant at anthesis stage with uniconzole treatments were higher than control in different sites.The contribution of nitrogen from nutritious organs to kernel after anthesis was between 76.9 percent and 82.9 percent, which occupied the most proportion to kernel. Uniconzole treatments increased the nitrogen translocation amount and translocation proportion in leaf, stem, sheath, root, spike axis and kernel husk. So the total translocation amount-, translocation proportion and ration to total kernel nitrogen were higher remarkably than control. The distribution amount and proportion of nitrogen to kernel at mature stage were heightened by uniconzole.Uniconzole treatments enhanced the soluble protein contents in flag leaves, the big difference existed from 0 to 20 days after anthesis, the content of soluble protein contents were low at 35 days after anthesis, but the treatments with uniconzole were still higher than control, which would be profitable to the photosynthesis and nitrogen assimilation, and beneficial to the transportation of nitrogen from leaves to kernels.5. Uniconzole accelerated the accumulation of protein in kernel.The content of non-protein nitrogen declined but protein nitrogen ascended, the protein content in kernel changed as 'V during grouting, the valley appeared at 25 or 30 days after anthesis. Uniconzole treatments improved the non-protein nitrogen at the beginning of grouting, which were kept from 5 to 20 days after anthesis. protein nitrogen and grain protein content also higher than control during the whole grain filling, the content of protein and the accumulation of protein were higher than control.6. Uniconzole treatments improved the quality of wheat kernel in different cultivars under different sites.In four sites and three cultivars, all of uniconzole treatments increased protein content, wet gluten content and zeleny sedimentation volume were improved, and dough developing time*, dough stability time were prolonged, too. Protein content and protein quality were increased, the protein yield were improved, too.7. The mechanism of uniconzole waterless-dressing seeds on the quality of winter wheat.At the metabolization level, uniconzole treatments improved the content of ZR, IAA and GA in kernel, which affected the development of nucleic acid and protein at transcription and translation process, the activation of RNA and protein accelerated the development of functional protein, the activities of GS> GOGAT-. GOT-. GPT were improved, which promoting the anabolism and conversion of amino acid in kernel, so the content and quality of protein were improved.On the other hand, uniconzole treatments improved the accumulation and transportation of carbohydrate and nitrogen. The nitrogen contents in different organs were enhanced at jointing and anthesis stage, the nitrogen accumulation per plant at anthesis stage were higher than control in different sites, uniconzole treatments increased the nitrogen translocation amount > translocation proportion and ration to total kernel nitrogen, the content of non-protein and protein nitrogen in kernel were increased. At the same time, uniconzole treatments increased the soluble sugar content in flag leaves at anthesis stage, the content of soluble sugar in kernel were improved too at the beginning of filling, which would be beneficial to the synthesize of starch and protein. So uniconzole treatments increased the content and quality of protein without the decrease of starch content.