选用 4个蛋白含量不同的小麦品种于全生育期测定叶片中NRA和植株中蛋白N含量 ,通过分析NRA动态变化及其与植株蛋白N的关系 ,结果表明 :4品种叶片NRA在全生育期表现为单峰曲线 ,峰值基本在扬花期 ,高蛋白品种能维持较长时期的较高NRA ;小麦植株体内蛋白N含量在抽穗前与NRA上升不同步 ,在抽穗后则与NRA同步变化。因此 ,可通过测定扬花期或其后各期叶片内NRA值来推测植株体内蛋白质含量的高低。 Four wheat cultivars with different protein contents were used to determine the NRA content and the N content in the plant during the whole growth period. The dynamic changes of NRA and its relationship with plant N were analyzed. The results showed that: The results showed that the highest NRA was observed in the high-protein cultivars at the flowering stage and the highest NRA in the long-term cultivars. The content of protein N in wheat plants was not synchronized with the NRA rise before heading, but changed synchronously with NRA after heading. Therefore, we can estimate the content of protein in the plant by determining the NRA value at the flowering stage or in subsequent stages.