| Nitrate and ammonia assimilation is an important process in plant growth and development. Fujiminori trees were sprayed with five foliar fertilizers of urea, ammonium nitrate, ammonium sulfate, ammonium chloride and sodium nitrate for the study of the effects of foliar fertilizers on grape Physical growth, Chlorophyll content and the changes of photosynthesis characteristic parameters which included net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs) and intercellular CO2 concentration (Ci) were measured in one day. A search of nitrogen metabolism genes from the VitisEST database revealed that there are many genes related to nitrogen assimilation and metabolism of glutamine, glutamic acid, aspartic acid and asparagine. Enzymes found were mainly nitrate reductase (NR), nitrite reductase (NiR), glutamine synthetase (GS), glutamate dehydrogenase (GDH) and asparagine synthetase (AS). Fluorescent quantitative PCR were used to analyze the expression of these genes after different treatment. Foliar application of nitrogen fertilizer by the amount of the different treatment effects on grape quality indicators, designed to provide a theoretical scientific basis for grape cultivation and fertilization, having a far-reaching significance for defining reasonable concentration and guiding the production of fertilizer. The specific research results are as follows:1.This study selected three new tips in fixed position before and after fertilization 15 days and measured length and mature leaves length and width, calculating the growth rate of branches and leaves and leaves’ area. This research used vernier caliper to measure the fruit vertical and horizontal diameter, weighed the single fruit quality by the weighing scales. The results indicated that The growth rate of new tips were increased in different treatment, and the leaf area was increased greatly in urea and ammonium nitrate treatment. The largest effect on fruit growth was from urea, ammonium sulfate treatment. Thus ammonium chloride are relatively small effect on fruit size.This research measured net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs) and intercellular CO2 concentration (Ci) by CIRAS-1 photosynthetic measurement system which was from the PP-System company. The results showed that the largest effects on transpiration was from urea treatment. The treatment of ammonium nitrate, ammonium sulfate and ammonium chloride took influences on transpiration in the afternoon session; Meanwhile, the largest effects on stomatal conductance was from urea treatment, this samed as transpiration. The variation tendency of Ci in different treatment was different. Most of the number was bigger, this was good for the photosynthesis. The changes of net photosynthetic rate in one day kept to the curve of "Twin peaks" model, It was not clear that every treatment had an influence on net photosynthetic rate in the "lunch break" period, there was no doubt that they affected it in other time, among them the influence of urea treatment was most significant.2. To understand gene response to fertilizer application, quantitative PCR were used to analyze the expression of five genes (VvGHD, VvNiR, VvNR, VvGS and VvAS) of ’Fujiminori’grape at different times with five foliar fertilizers of urea, ammonium nitrate, ammonium sulfate, ammonium chloride and sodium nitrate. The results showed that the expression levels of five genes exhibit significant differences at different times after different treatment, the expression was increased significantly by application of 0.3% of nitrogen fertilizer and kept a long time. The effect of urea treatment was most significant. The period which was affected by ammonium nitrate and ammonium sulfate treatment was relatively concentrated meanwhile the induction period which was affected by ammonium chloride and sodium nitrate treatment was diffusion and the effect was remarkable. |
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