摘要
Soil salinity is one of the most severe abiotic stress factors threatening agriculture worldwide. Hence,particular interest exists in unraveling mechanisms leading to salt tolerance and improved crop plant performance onsaline soils. Barley is considered to be one of the most salinity-tolerant crops, but varying levels of tolerance are wellcharacterized. A proteomic analysis of the roots of two contrasting cultivars （cv. Steptoe and cv. Morex） is presented.Young plants were exposed to a period of 1, 4, 7, or 10 d at 0, 100, or 150mM NaCI. The root proteome was analyzedbased on two-dimensional gel electrophoresis. A number of cultivar-specific and salinity stress-responsive proteins wereidentified. Mass spectrometry-based identification was successful for 74 proteins, and a hierarchical clustering analysisgrouped these into five clusters based on similarity of expression profile. The rank product method was applied to sta-tistically access the early and late responses, and this delivered a number of new candidate proteins underlying salinitytolerance in barley. Among these were some germin-like proteins, some pathogenesis-related proteins, and numerousas-yet uncharacterized proteins. Notably, proteins involved in detoxification pathways and terpenoid biosynthesis weredetected as early responsive to salinity and may function as a means of modulating growth-regulating mechanisms andmembrane stability via fine tuning of phytohormone and secondary metabolism in the root.
