| Rapeseed, especially Brassica napus is one of an important oil crop in China. Planting area and yield are the highest in the world. Now, with its production advantage in Brassica napus were used the planting of large area in the world. Nitrogen is necessary nutrients for plant growth, and the demand of nitrogen is also very big for plants. Brassica napus, needs so much nitrogen fertilizer that will increase the cost of agriculture and even bring serious problems such as environmental pollution. This experiment is in microspore culture of46different genotypes DH of new-type, which were used by high nitrogen(HN) and low nitrogen(LN) two nitrogen processing under the condition of two hydroponic seedling screening efficiency genotype, and gained survey their physiological indexes, and then to filter out of different genotype materials in large field, and get the F1seeds. Mechanism of high nitrogen use efficiency was studied by the determination and analysis of several physiological and biochemical indexes through nutrition solution culture or pot experiments. The pot experiment of different genotypes of high efficient material grain by using Fourier transform near red spectrometer to analyze the quality of the grain. At the same time, through hydroponic experiment, comparing different nitrogen efficiency of parents and hybrid F1generation of nitrate transporter NRT related gene expression differences. The results were showed as follows:1. Through Different levels of nitrogen nutrient solution culture experiment, several extreme materials had been screened. There were high nitrogen efficient new-type Brassica napus D4-15and low nitrogen efficient new-type Brassica rapa D2-1;2. The new-typed Brassica napus had large potential, but should be made homozygous first. By preliminary screening we are got high and low efficiency geneotypes of different materials, in the fields of breeding, by hybridzation we had got16hibird materials, which provided a solid foundation for further systematic research.3. Nutrition solution culture and pot experiments were set to these materials with different nitrogen efficiency of parents and hybirds, and several physiological and biochemical indexes were determined. The results showed that under LN condition the growth of high nitrogen efficient F1superior to parents, which could form a better developed roots; they had more green leaves, and their old leaves contained more chlorophyll to keep higher photosynthetic capacity. With these characters, high nitrogen efficient materials could accumulated more nitrogen, synthesize more photosynthate, form larger biomass.4. Either high N or low N conditions, the trend of the expression of NRT1.1and NRT2.1for parents and hybrid is consistent. There is no significant difference with the expression level of shoot NRT between both efficiency genotypes, while there is significant difference with the expression level of root NRT. The relative expression level of high N efficiency genotype is significant lower than that of low N efficient genotype, while the variation of relative expression of the former is higher than the latter.5. Different nitrogen levels on parents and hybrid F1generation rape had a greater influence on the grain quality. Increasing nitrogen application, will significantly reduce the rape seed oil content, but the grain protein content is increased with the increasing of nitrogen. Parent seed glucoside of sulfur content and decreased with the increase of nitrogen, the filial generation just the opposite; Increasing nitrogen application, can increase the palmitic acid stearic acid in fatty acids oleic acid content of linoleic acid, but the content of linolenic acid was decreased with increasing of nitrogen. |
PDF Full Text Request