低氮营养下小麦氮素高效吸收利用的生理机理

小麦生产中大量施用氮肥是导致氮肥利用效率降低的主要原因，培育氮高效小麦品种是降低氮肥用量、提高氮肥利用效率、减轻环境污染的重要途径。本研究选用低氮营养下氮效率有差异的小麦品种，采用水培试验和田间土柱试验相结合的方法，系统分析低氮营养下植株内源激素平衡的变化特征及其与根系形态建成的关系，明确小麦根系NO3-吸收载体基因表达特征及其调控机制，揭示低氮营养调控氮素同化与再动员的生理机制及其与光合作用和C代谢的关系，进而阐明低氮营养下小麦氮素高效吸收利用的生理与分子机理。研究结果为选育氮高效的小麦品种提供理论依据，同时为小麦高产高效生产提供理论依据和技术支持。

As using large amounts of nitrogen fertilizer is a main problem of leading to the decrease of nitrogen use efficiency in wheat production, cultivating nitrogen uptake wheat varieties is an effective way to reduce nitrogen fertilizer, increase nitrogen use efficiency and relieve environmental pollution. To study different low nitrogen tolerance varieties of wheat seedling stage growth and the distribution of accumulated nitrogen, we employed two nitrogen uptake wheat varieties which has different response characteristics of low nitrogen, combining a hydroponic experiment and field soil column culture experiment methods. We need to analyze the effects of low nitrogen on root growth, and the relationships with phytohormone content in low nitrogen nutrition, clear low nitrogen nutrition of wheat root NO3- uptake carrier NRT2.1 expression characteristics and regulation mechanism, reveal low nitrogen nutrient induced nitrogen assimilation and mobilize the physiological mechanism and its relationship with photosynthesis and carbon metabolism. Then clarify the physiology and molecular mechanisms of wheat nitrogen uptake and use in low nitrogen nutrition. The results could provide theory basis for breeding wheat cultivations and offer technical support for high yield and efficient production in wheat.