Group of Molecular and Functional Plant Biology, Research Institute for Bioresources, Okayama University, Kurashiki, Okayama 710-0046, Japan.
Trends Plant Sci. 2009 Dec;14(12):660-8. doi: 10.1016/j.tplants.2009.08.009. Epub 2009 Sep 25.
The salinization of irrigated lands is increasingly detrimental to plant biomass production and agricultural productivity, as most plant species are sensitive to high concentrations of sodium (Na(+)), which causes combined Na(+) toxicity and osmotic stress. Plants have multiple Na(+)-transport systems to circumvent Na(+) toxicity. Essential physiological functions of major Na(+) transporters and their mechanisms mediating salinity resistance have been identified in Arabidopsis , including the AtSOS1, AtNHX and AtHKT1;1 transporters. As we discuss here, recent studies have demonstrated that a class of xylem-parenchyma-expressed Na(+)-permeable plant HKT transporters represent a primary mechanism mediating salt tolerance and Na(+) exclusion from leaves in Arabidopsis, and that major salt-tolerance quantitative trait loci in monocot crop plants are also based on this HKT-mediated mechanism.
灌溉土地的盐渍化对植物生物量和农业生产力的影响越来越大,因为大多数植物物种对高浓度的钠(Na(+))敏感,这会导致 Na(+)毒性和渗透胁迫的结合。植物有多种 Na(+)-运输系统来规避 Na(+)毒性。在拟南芥中,已经确定了主要 Na(+)转运体的基本生理功能及其介导耐盐性的机制,包括 AtSOS1、AtNHX 和 AtHKT1;1 转运体。正如我们在这里讨论的那样,最近的研究表明,一类木质部-薄壁细胞表达的 Na(+)-可渗透植物 HKT 转运体是介导拟南芥耐盐性和 Na(+)从叶片中排出的主要机制,单子叶作物植物中的主要耐盐性数量性状也基于这种 HKT 介导的机制。