The Research On Response Of Different Genotype Maize To Light And Nitrogen

In this research, Zi330, Zong31 and 148 introgression lines(ILs) (BC4F2) which backgroud parent is NongXi110 were selected as test materials to compare nitrate reductase and glutamine synthetase activity, root dry weight, shoot dry weight of maize seedlings under the conditions of different nitrogen and light treatments, as well as, differences in economic output under fertilizer and no fertilizer field conditions. The results are as follows:(1) The different genotypes seedlings have the different response to various concentrations of nitrogen. High nitrogen use efficiency materials have a more width suitable concentration for the root, shoot growth than low nitrogen use efficiency materials, but the highest concentration can not exceed 8.00 mmol/L. The stress concentration which is less than or equal to 2.00 mmol/L is used good to evaluate nitrogen use efficiency of different genotypes.(2) Based on the hydroponic culture methods,the light intensity affects the performance of nitrogen use efficiency. The relationships between the root dry weight under the light intensity 9000 lx, the nitrogen concentration of 2.00 mmol/L ~ 4.00 mmol/L and the economic output in the field , as well as,the glutamine synthetase activity and the economic output under the conditions of fertilization are positive correlation. However, in low-light intensity (2000 lx), the root dry weight, glutamine synthetase activity both are negative correlation with yield.(3) The genotypes with different nitrogen use efficiency have the different best combination of nitrogen and light intensity ,and the combination is not a simple addition bettwen light and nitrogen. When the best combination of nitrogen and light intensity apearance, the test materials with low nitrogen use efficiency need less nitrogen or lower light intensity than that with high nitrogen use efficiency.(4) Light is the main factor affecting biomass, genotype is the key factors affecting nitrate reductase, and the interaction among light, nitrogen and genotype is the most important factor for glutamine synthetase .(5) The Introgression Lines of NongXi110 under the different light and nitrogen condtions were dealt with to map QTL, and two QTL for root dry weight were detected on chromosome 7 and chromosome10. Six QTLs for nitrate reductase were detected on two chromosomes(chromosome 1, chromosome 10). Four QTLs for glutamine synthetase were detected on 4 chromosomes(chromosome 2,4,8,10).(6) One material with high nitrogen use efficiency was selected from the test materials. Its donor parent is HuangZaoSi and background parent is NongXi110(BC4F2).