基于干旱锻炼的马铃薯耐旱性增强的生理机理及候选基因的挖掘

Potato is very sensitive to drought stress during the tuber growth stage, and the drought is one of the most important ecological adversity factors limiting potato production in China and even in the world. Previous studies mainly focused on the effects of irrigation or planting patterns on drought tolerance in cultivars, or on breeding of cultivars with drought tolerance, however, the physiological mechanisms of drought tolerance enhancement of plants after drought priming are still unclear, and mining of candidate genes for drought tolerance enhancement need further investigation. Our previous studies found that drought priming at seedling stage improved the water status of plant leaves after drought stress at tuber growth stage, and we proposed that drought priming might enhance drought tolerance of plants during later stages, but the mechanism was still unknown. In this study, two potato cultivars with different drought tolerance were used to understand the effects on carbon assimilation metabolism and root growth characteristics of plants treated by drought priming and drought stress, which in order to clarify the physiological mechanisms of drought tolerance enhancement in potato after drought priming. On this basis, RNA-Seq will be used to screen candidate genes for drought tolerance enhancement, and then the functions of key candidate genes will be verified by developing constructs of RNA interference and gene over-expression, so as to preliminarily reveal the molecular mechanism of drought tolerance enhancement in potato. These results might provide new theoretical basis and genetic resources for potato drought tolerance breeding.

马铃薯在块茎增长期对干旱胁迫非常敏感,干旱成为限制我国乃至世界马铃薯生产最主要的生态逆境因子之一。以往的研究大多集中在灌溉模式和种植模式对品种耐旱性的影响以及耐旱性品种的选育等方面，干旱锻炼后耐旱性增强的生理机理及候选基因的挖掘有待于进一步深入研究。申请人前期研究发现，苗期干旱锻炼改善了块茎增长期干旱胁迫后植株叶片的水分状况，推测可增强植株的耐旱性，但机理尚不明确。本课题以具有耐旱性差异的两个马铃薯品种为材料，通过研究干旱锻炼和干旱胁迫对马铃薯植株碳代谢以及根系生长特性的影响，以明晰干旱锻炼后马铃薯耐旱性增强的生理机理。在此基础上，运用RNA-Seq测序技术筛选耐旱性增强的候选基因，并通过构建RNA干扰沉默载体和基因过表达载体来验证关键候选基因的功能，以期初步揭示马铃薯耐旱性增强的分子机理。研究结果可为马铃薯耐旱性育种提供新的理论依据和基因资源。

马铃薯在块茎增长期对干旱胁迫非常敏感,干旱成为限制我国乃至世界马铃薯生产最主要的生态逆境因子之一。以往的研究大多集中在灌溉模式和种植模式对品种耐旱性的影响以及耐旱性品种的选育等方面，干旱锻炼后耐旱性增强的生理机理及候选基因的挖掘有待于进一步深入研究。申请人前期研究发现，苗期干旱锻炼改善了块茎增长期干旱胁迫后植株叶片的水分状况，推测可增强植株的耐旱性，但机理尚不明确。本课题以具有耐旱性差异的两个马铃薯品种为材料，通过研究干旱锻炼和干旱胁迫对马铃薯植株碳代谢以及根系生长特性的影响，以明晰干旱锻炼后马铃薯耐旱性增强的生理机理。在此基础上，运用RNA-Seq测序技术筛选耐旱性增强的候选基因，并通过构建RNA干扰沉默载体和基因过表达载体来验证关键候选基因的功能，以期初步揭示马铃薯耐旱性增强的分子机理。研究结果可为马铃薯耐旱性育种提供新的理论依据和基因资源。