姚启伦　霍仕平　张俊军

摘要： 以4个不同的玉米自交系为材料，对高温、干旱处理后的苗期植株进行转录组测序。玉米自交系响应高温和干旱胁迫的差异表达基因（DEGs）分别为6 966和6 272个，在高温和干旱胁迫下4个玉米自交系相同的DEGs分别是705和871个。同时响应高温和干旱的DEGs有100个。在耐旱、耐热性强的玉米自交系中鉴定出18个特异的DEGs，其中锌指转录因子、WRKY转录因子、GT转录因子和B2热激转录因子在胁迫响应中发挥关键的调控作用。KEGG通路分析结果表明，耐旱、耐热性强玉米自交响应高温干旱胁迫的DEGs富集在生物学过程、分子功能、代谢过程、遍在蛋白代谢和氮代谢途径5条通路。热带、亚热带玉米种质的耐旱、耐热性强于温带玉米种质，可在热带、亚热带玉米種质中有效筛选耐旱、耐热基因。

关键词： 玉米自交系;高温、干旱胁迫;转录组;差异表达基因;通路

中图分类号： S513 文献标识码： A 文章编号： 1000-4440（2021）01-0029-09

Key genes and pathways of maize inbred lines responding to heat and drought stress

YAO Qi-lun1， HUO Shi-ping2， ZHANG Jun-jun3

（1.School of Advanced Agriculture and Bioengineering， Yangtze Normal University， Chongqing 408100， China;2.Chongqing Three Gorges Acodemy of Agricultural Science， Chongqing 404100， China;3.Heilongjiang Hetian Fengze Agriculture Science and Technology Development Co.， Ltd.， Harbin  067500， China）

Abstract： Transcriptome sequencing of the four different maize inbred lines subjected to high temperatures and water deficits， was performed at the stage of seedling. In total， 6 966 heat-responsive and 6 272 drought-responsive differentially expressed genes（DEGs） were identified in the four maize lines. In addition， 705 and 871 DEGs were identified as being commonly associated with heat and drought stress， respectively. There were 100 DEGs responding to both heat and drought stress. Eighteen DEGs were identified in maize inbred lines with strong drought tolerance and heat tolerance. The zinc finger transcription factor， WRKY transcription factor， GT transcription factor and B2 heat shock transcription factor played key regulatory roles in stress response. Analyses of KEGG pathway enrichment showed that the pathways such as biological process， molecular function， metabolic process， protein ubiquitination metabolism and nitrogen metabolism were the most highly enriched in the maize lines tolerant to heat and drought. It can be concluded that tropical and subtropical maize is tolerant to heat and drought， implying that it is plausible to screen goal genes in the tropical and subtropical germplasm.

Key words： maize inbred lines;heat and drought stress;transcriptome;differentially expressed genes（DEGs）;pathways

高温和干旱是抑制玉米生长发育、制约玉米产量的主要非生物胁迫因子[1]。在干旱、半干旱区，玉米往往受到高温干旱复合胁迫的不利影响[2-3]。全球有43 %的干旱、半干旱耕地，中国干旱、半干旱土地面积约占全国土地面积的近50 %[4-5]。随着温室效应加剧，预计到本世纪末地表气温将上升1～5 ℃，1980-2008年，高温胁迫导致全球玉米产量下降3.8%[6-7]。因此，筛选玉米耐旱、耐热基因，培育耐旱、耐热品种一直是玉米育种界面临的重大课题。迄今关于高温、干旱胁迫对玉米植株形态、生理生化和产量品质不利影响的研究已有较多文献报道。……