Identification and validation of a novel major QTL for harvest index in rice (Oryza sativa L.)

作者：Shaohong Zhang, Xiuying He, Junliang Zhao, Yongsheng Cheng, Zhimei Xie, Yuehan Chen, Tifeng Yang, Jingfang Dong, Xiaofei Wang, Qing Liu, Wei Liu, Xingxue Mao, Hua Fu, Zhaoming Chen, Liao Yaoping, Bin Liu · 发表于：Rice · 年份：2017 · DOI：10.1186/s12284-017-0183-0 · 被引用次数：22 · 研究领域：Genetic Mapping and Diversity in Plants and Animals、Rice Cultivation and Yield Improvement、GABA and Rice Research

BACKGROUND: Harvest index (HI) in rice is defined as the ratio of grain yield (GY) to biomass (BM). Although it has been demonstrated that HI is significantly related to yield and is considered as one of the most important traits in high-yielding rice breeding, HI-based high-yielding rice breeding is difficult due to its polygenic nature and insufficient knowledge on the genetic basis of HI. Therefore, searching for rice varieties with high HI and mapping genes associated with high HI can facilitate marker-assisted breeding for high HI in rice. RESULTS: Yuexiangzhan, a popular indica cultivar with good reputation of high HI was crossed with Shengbasimiao, an indica cultivar with lower HI to develop a recombinant inbred line population, and QTL mapping for HI and its component traits was conducted. In total, five QTLs for HI, three QTLs for GY, and six QTLs for BM were detected in two-year experiments. Among the three GY QTLs, one co-located with the HI QTL on chromosome 8, while the other two co-located with the two tightly-linked BM QTLs on chromosome 3. The co-located QTLs in each of the chromosomal regions produced additive effects in the same direction. Particularly, the HI QTL on chromosome 8, qHI-8, could be detected across two years and explained 42.8% and 44.5% of the phenotypic variation, respectively. The existence of qHI-8 was confirmed by the evaluation of the near isogenic lines derived from a residual heterozygous line, and this QTL was delimitated to a 1070 kb ...