模拟干旱对甘薯近缘野生种[Ipomoea trifida(Kunth) G. Don]生理特性和基因表达谱的影响

Physiological characteristics and gene expression profiles of wild sweetpotato relative Ipomoea trifida （Kunth） G. Don under dehydration stress

本文研究分析30%浓度的PEG-6000模拟干旱胁迫对甘薯二倍体近缘野生种（Ipomoea trifida）幼苗生理指标的影响,并在此基础上利用高通量测序技术,进行转录组测序和基因表达谱分析。结果表明：随着干旱胁迫时间的延长,叶片超氧化物歧化酶（SOD）和过氧化物酶（POD）活性增强、丙二醛（MDA）含量增加。其中,SOD、POD活性和MDA含量在胁迫6 h变化显著;转录组测序共得到40 385 764条净数据和7 600 078 117 bp数据量,de novo组装产生了65 174条转录本,N50为1 638 bp。通过干旱处理（干旱胁迫6 h）和对照组（对照0和6 h）之间基因差异表达分析,共有1 763个基因差异表达,其中557个基因上调表达,1 206个基因下调表达,下调表达基因的数量明显高于上调基因。

In this study, PEG-6000 at 30% concentration was used to simulate the effects of drought stress on physiological and biochemical indexes of diploid Ipomoea trifida seedlings. High-throughput sequencing tech- nique was used for the analysis of the transcriptom and gene differential expression profiles. The results showed that SOD, POD activities and MDA content increased with the stress treatment time prolonged, during which the significant variation time point was at 6 h. The transcriptome sequencing showed that a total of 40 385 764 reads and 7 600 078 117 bp clean data was obtained. The de novo assembly produced 65 174 1. trifida tran- scripts, with an N50 of 1 638 bp. A total of 1 763 genes were significantly different expressed, in which 557 genes were up-regulated, 1 206 genes down-regulated by analysis between treatment group （Treatment 6 h） and control group （CK 0 h and CK 6 h）. The down-regulated genes were significantly higher than the up-regulated genes.