水稻种子耐低温发芽力的QTL定位及上位性分析

QTL and Epistasis for Low Temperature Germinability in Rice

利用种植在不同环境[南京(2002)、海南(2002—2003)、南京(2003)]下的Kinmaze/DV85重组自交系(RILs)群体,对水稻种子萌发第10天的低温发芽力进行QTL分析。利用QTLmapping2.0软件共检测到11个QTL,其中qLTG-7和qLTG-11可在3个环境中稳定表达,且最大贡献率均达到27.93%,增强低温发芽的基因分别来自Kinmaze和DV85。与前人的研究比较发现,这2个QTL可以在不同环境下和遗传背景中稳定表达。进一步上位性分析的结果表明,qLTG-11并不参与上位性互作,而qLTG-7虽参与互作但其贡献率较小。

High germination ability at relatively low temperature is essential for direct-seeding rice varieties. A recombinant inbred line population （RILs）, derived from a cross between varieties Kinmaze （japonica） and DV85 （indica） was used to detect QTL for low temperature germinability （LTG）. The germination rate at 15℃ after 10 d germination culture in Nanjing, Jiangsu Province, and in Lingshui, Hainan Province, in 2002 and in Nanjing in 2003 was taken as LTG indicator. A total of 11 QTL on chromosomes 2, 5, 7, 8, 11, and 12 were detected in the above three seed production environments. Of these, QTL on chromosomes 7 and 11 mapped in similar genomic regions in all experiments and the maximum percentage of phenotypic variation explained （PVE） by each QTL was 27.93%, while epistatic interaction had slightly low PVE.