中文摘要：

杂种优势现象广泛应用于作物生产中，但其形成的遗传机理尚不十分清楚。目前．基因组学的快速发展为植物杂种优势机理研究带来机遇．大量研究发现和证实杂交子一代与其亲本之间存在全基因组水平的基因表达和表观遗传修饰差异。将这些差异与杂种优势表现联系起来是该方向研究的重点和难点。针对特定性状。采用全基因组关联分析鉴定其杂种优势的候选基因．结合细胞或组织特异性转录组比较．可能为植物杂种优势分子机理研究带来突破。

英文摘要：

Heterosis has been utilized widely in crop produc- tion, whereas the underlying genetic basis was not fully understood. The recent rapid development of genomics provides opportunity to explore the mechanism of hetero- sis in plants. Many studies revealed that there are ge- nome-wide differences of gene expression and epigenetic modifications between hybrid and their parents. It is im- portant but difficult to build connection between these differences and heterosis manifestation. Combining the identification of candidate genes for heterosis by ge- nome-wide association analysis with the comparison of cellor tissue-specific transcriptomes may lead to break- through on the research of molecular mechanism of het- erosis in plant.