Identification of Heat-Tolerance Genes using an Introgression Line from Yuanjiang Common Wild Rice (Oryza rufipogon)

摘要

Heat stress severely affects rice (Oryza sativa L.) growth, yield and milling quality. It is very important to breed heat-tolerant rice varieties to adapt to global warming year by year. However, heat tolerance is a very complex quantitative trait, and only a few related genes were cloned in the past few decades. Previously, we generated introgression lines with Teqing (Oryza sativa L. sspp. indica) as the background and Yuanjiang common wild rice (Oryza rufipogon Griff.) as the donor, and subsequently found that the line YIL106 carried three heat-sensitive QTLs. Here, we integrated microarray and QTL mapping methods to uncover candidate genes conferring heat-sensitivity at the seedling stage of YIL106. 33 genes with response to abiotic stress were chosen for further investigation. After annotation analysis of the Rice Gene Ontology Database, three candidate heat stress responsive genes, LOC_Os01g19020, LOC_Os01g23630, and LOC_Os12g43440, were selected. Moreover, overexpression of LOC_Os12g43440 greatly increased rice heat tolerance at the seedling stage. This work uncovers a novel gene for heat tolerance with potential value in breeding.