氮素是高粱生产中最昂贵的投入之一,故鉴定出有效地利用氮素的基因型越来越重要。氮素利用率的定义很多,而且不尽相同,从广义上的单位总氮量的生物产量到狭义上的单位叶面积氮量的光合作用。这些定义常用于描述氮素在代谢功能方面的有效性,但均忽略了植株把氮素吸入体内时为平衡所需的吸收部分。氮素吸收和利用的依存关系尚不很清楚,如高 Nitrogen is one of the most expensive inputs in sorghum production and therefore identifying genotypes that efficiently utilize nitrogen is increasingly important. Nitrogen utilization is defined in many ways and varies widely, from the broad-based biological yield of total nitrogen to the photosynthesis of nitrogen per unit leaf area in a narrow sense. These definitions are often used to describe the effectiveness of nitrogen in metabolic function, but all neglect the absorption needed for the plant to balance nitrogen uptake into the body. The dependence of nitrogen uptake and utilization is not well understood, such as high