Wang Yue, Ju Di, Yang Xueqing, Ma Dianrong, Wang Xiaoqi
Key Laboratory of Economical and Applied Entomology of Liaoning Province, College of Plant Protection, Shenyang Agricultural University, Shenyang, China.
Rice Research Institute, Shenyang Agricultural University, Shenyang, China.
Front Physiol. 2018 Nov 30;9:1717. doi: 10.3389/fphys.2018.01717. eCollection 2018.
The striped stem borer, (Walker), is a notorious pest of rice that causes large losses in China. Breeding and screening of resistance rice cultivars are effective strategies for management. In this study, insect-resistant traits of 47 rice cultivars were investigated by artificial infestation (AI) both in field and greenhouse experiments, using the susceptible (S) cultivar 1665 as a control. Results suggest that two rice cultivars, namely 1688 and 1654, are resistant (R) and moderately resistant (MR) to , respectively. Then, a comparative transcriptome (RNA-Seq) was assembled and differentially expressed genes (DEGs) with altered expression levels were investigated among cultivars 1688, 1654, and 1665, with or without infestation for 24 h. A total of 2569 and 1861 genes were up-regulated, and 3852 and 1861 genes were down-regulated in cultivars 1688 and 1654, respectively after artificial infestation with compared to the non-infested control (CK). For the susceptible cultivar 1665, a total of 882 genes were up-regulated and 3863 genes were down-regulated after artificial infestation with compared to the CK. Twenty four DEGs belong to proteinase inhibitor, lectin and chitinase gene families; plant hormone signal transduction and plant-pathogen interaction pathways were selected as candidate genes to test their possible role in resistance. RT-qPCR results revealed that 13 genes were significantly up-regulated and 8 were significantly down-regulated in the resistant cultivar 1688 with artificial infestation (1688AI) compared to the CK. Three genes, , , and , showed more than a 10-fold higher expression in 1688AI than in 1688CK, suggesting their potential role in insect resistance. Overall, our results provide an important foundation for further understanding the insect resistance mechanisms of selected resistant varieties that will help us to breed resistant rice varieties.
二化螟（Walker）是一种臭名昭著的水稻害虫，在中国造成了巨大损失。培育和筛选抗虫水稻品种是害虫治理的有效策略。在本研究中，以感虫品种1665为对照，通过田间和温室人工接虫试验，对47个水稻品种的抗虫特性进行了研究。结果表明，两个水稻品种1688和1654分别对二化螟表现为抗虫（R）和中抗（MR）。然后，构建了比较转录组（RNA测序），并研究了品种1688、1654和1665在接虫或未接虫24小时后表达水平发生改变的差异表达基因（DEG）。与未接虫对照（CK）相比，人工接虫后，品种1688和1654分别有2569个和1861个基因上调，3852个和1861个基因下调。对于感虫品种1665，与CK相比，人工接虫后共有882个基因上调，3863个基因下调。24个DEG属于蛋白酶抑制剂、凝集素和几丁质酶基因家族；选择植物激素信号转导和植物-病原体相互作用途径作为候选基因，以测试它们在抗二化螟中的可能作用。实时定量PCR结果显示，与CK相比，抗虫品种1688在人工接虫（1688AI）后有13个基因显著上调，8个基因显著下调。三个基因，即[具体基因1]、[具体基因2]和[具体基因3]，在1688AI中的表达比在1688CK中高10倍以上，表明它们在抗虫中的潜在作用。总体而言，我们的结果为进一步了解所选抗性品种的抗虫机制提供了重要基础，这将有助于我们培育抗二化螟水稻品种。
