The Expression Differences Study On The NRT Rape Genes Of Different Nitrogen Efficiency

Brassica napus has a great requirement of N. For a long time, we are too eager tomanure the farm with a great amount of N fertilizer, which increase the cost on agriculturaland lead to the destruction and pollution of the ecological environment. Thus, finding a wayto reduce the amount of N fertilizer and improve the rape species to promote the Navailability has become the most urgent issue to study in plant nutrition field. Screening highN efficiency genotype and finding out the differences between different N efficiencygenotype and then to reveal the molecular mechanism of how the rape use N in highefficiency is the foundation to research this issue. In our study, we select Brassica napus asexperimental material, and select high N high efficient genotype, low N high efficientgenotype, high N low efficient genotype and low nitrogen low efficient genotype rapeseedvarieties from the result of preliminary study. Through the use of solid medium andhydroponic culture, we make a comparison of differences in NRT gene’s expression in timeand space and differences in regulation of gene’s expression between different N efficiencyNRT genes of Brassica napus. The main results are as follows:(1) Either high N or low N conditions, the relative expression level of root NRT1.1ofhigh N efficiency genotype is significant higher than that of low N efficient genotype, whilethere is no significant difference with the expression level of NRT2.1.(2) When use nitrate nitrogen as N source, the relative expression level of root NRT1.1ofhigh N efficiency genotype is significant higher than that of low N efficient genotype, whilethere is no significant difference with the expression level of NRT2.1. But when use theammonium as N source, there is no significant difference with the NRT1.1expression levelbetween both efficiency genotypes, and there is a trend that the expression level of rootNRT2.1of high N efficiency is lower than that of low N efficiency genotype.(3) Under normal P supply condition, there is a trend that the expression level of rootNRT1.1and NRT2.1of high N efficiency is higher than that of low N efficiency genotype. Butunder low P supply condition, the expression level of root NRT1.1of high N efficiencygenotype is still higher than that of low N efficiency genotype, while there is a trend that the expression level of root NRT2.1of high N efficiency genotype is lower than that of low Nefficiency genotype.