作物硝态氮转运利用与氮素利用效率的关系  

The relationship between nitrate transport and utilization in crop and nitrogen utilization efficiency

作　　者：张振华[1] ZHANG Zhen-hua(College of Resource ＆ Environment, Southern Regional Collaborative Innovation Center for Grain and Oil Crops in China/Hunan Agricultural University, Changsha 410128, China)

机构地区：[1]南方粮油作物协同创新中心/湖南农业大学资源环境学院,长沙410128

出　　处：《植物营养与肥料学报》2017年第1期217-223,共7页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(31101596);湖南省高校创新平台开放基金项目(13K062);湖南省百人计划项目资助

摘　　要：【目的】铵态氮(NH_4^+)和硝态氮(NO_3~–)是作物氮素吸收利用的主要形态,旱作作物NO_3~–的累积与利用是氮素营养研究的主要组成部分,关系到理解作物NO_3~–的转运和利用关系及作物体内NO_3~–含量和氮素利用效率(nitrogen utilization efficiency,NUE)高低的问题。【主要进展】作物吸收的NO_3~–分为被作物直接利用、分泌到根外、储存在液泡和向地上部分运输四种途径。其中NO_3~–短途分配(液泡NO_3~–分配)和长途转运(地上、地下部NO_3~–的转运)共同调控着NO_3~–的利用效率,进而影响作物的NUE。液泡NO_3~–不能被作物直接利用,只有分配到液泡外细胞质中的NO_3~–才能被作物迅速代谢和利用;同时有更大比例的NO_3~–分配到地上部分,使得作物可以充分利用太阳光能进行NO_3~–代谢和能量转换,从而提高了作物的NUE。此外,液泡对NO_3~–起到分隔作用,储存在液泡中的NO_3~–并不能对NO_3~–转运相关基因(如NR、NO_3~–长途转运基因NRT1.5和NRT1.8)起到诱导效果;只有分配在液泡外原生质体中的NO_3~–才能对NO_3~–诱导基因产生强烈的诱导。因此,作物细胞原生质体中液泡内、外NO_3~–的分配不仅影响了NO_3~–的同化利用,而且直接影响了NO_3~–的长途转运。【展望】本文对植物原生质体中液泡内、外NO_3~–的短途分配和地上、地下部间NO_3~–的长途转运机制进行了总结,为进一步深入研究作物地上、地下部NO_3~–长途转运和液泡NO_3~–短途分配的关系,以及更好地揭示作物NUE对NO_3~–转运和利用的响应机理提供参考。【Objectives】Ammonia（NH_4＋） and nitrate（NO_3–） are the primary forms for crop nitrogen（N）absorption and utilization. NO_3– accumulation and utilization in plant tissues of dry land crops are the main components of N nutrient study, which are related to the NO_3– content and N utilization efficiency（NUE） in plant tissues. 【Main advances】 Absorbed NO_3– in crop can be assimilated into organic N directly, secreted to the root, accumulated into vacuolar space and transported from roots to shoots. NO_3– utilization efficiency and NUE were regulated by NO_3– short distribution（vacuole NO_3– distribution） and NO_3– long transportation（between roots and shoots）. Vacuole NO_3– can not be assimilated into organic N, but the NO_3– outside of the vacuole in protoplast can be utilized by crop directly. The higher proportion of NO_3– in shoots has higher NUE, because the NO_3–assimilation in shoots will take full advantage of the solar energy. In addition, NO_3– is separated by vacuole, NO_3–assimilation genes（NR） and transportation genes（NRT1.5 and NRT1.8 for long transport of NO_3–） can not be induced by vacuole NO_3–, but can be stimulated by the cytosolic NO_3–. Consequently, not only NO_3– assimilation is regulated by NO_3– short distribution, but also affected the NO_3– long transport between roots and shoots.【Prospective】We summarized the mechanisms of NO_3– short distribution and long transportation in this review, and provided some implications for further study on the relationship between NO_3– long transportation and vacuole NO_3– short distribution, and the response of crop NUE to NO_3– transportation and utilization.

关 键 词：硝态氮 氮素利用效率 长途转运 短途分配 

分 类 号：S311[农业科学—作物栽培与耕作技术]