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玉米氮效率的评价方法与指标不尽一致,导致对玉米基因型不同的分类结果。玉米氮效率研究主要集中于根系对氮素的吸收、叶片对氮素的还原同化、氮素在植株体内的积累和分配以及地上部生长势与氮效率的关系方面。以子粒为主要收获对象的玉米,穗、子粒发育状况对玉米产量起着关键作用,有关穗、子粒发育对玉米氮效率贡献率的大小、不同氮效率基因型玉米穗、子粒发育的差异以及内在生理生化机制研究较少。对不同氮效率基因型玉米子粒发育与氮效率之间关系、子粒发育尤其是顶部子粒的早期发育(决定穗粒数的形成)对氮素的反应、氮高效品种顶部子粒的早期发育是否优于氮低效型、氮素对不同氮效率基因型玉米子粒发育的影响机制等问题有待进一步研究。
The evaluation methods and indexes of maize nitrogen efficiency are not consistent, leading to different classification results for maize genotypes. Nitrogen efficiency in maize mainly focused on the uptake of nitrogen by roots, the reduction and assimilation of nitrogen by leaves, the accumulation and distribution of nitrogen in plants, and the relationship between shoot growth potential and nitrogen efficiency. The developmental status of maize, ear and grain which are mainly harvested by the grain are the key factors for the yield of maize. The contribution rate of ear and grain development to the nitrogen efficiency of maize and the differences of ear and grain development of different nitrogen efficiency genotypes Physiological and biochemical mechanisms are less studied. The relationship between the development of nitrogen-efficient genotypes of maize and nitrogen efficiency, the development of grain development, especially the early development of top grains (determining the number of grains per spike) Nitrogen inefficient, the mechanism of nitrogen on the development of different nitrogen efficiency genotypes maize grain needs further study.