Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan; Department of Agronomy, National Taiwan University, Taipei 106, Taiwan.
Institute of Plant and Microbial Biology, Academia Sinica, Nankang, Taipei 115, Taiwan.
Plant Sci. 2016 Jan;242:187-194. doi: 10.1016/j.plantsci.2015.09.005. Epub 2015 Sep 10.
Rice is a facultative short-day plant, and it requires a photoperiod shorter than the critical day length to get flowering. Sensitivity to photoperiod has been suggested as a major selection target in cultivated or weedy rice. The modern rice varieties in Taiwan may be cultivated twice a year. These varieties contain loss-of-function of two important flowering-time related genes, Heading date 1 (Hd1) and Early heading date 1 (Ehd1), and are mainly from a mega variety, Taichung 65. However, the parental lines of this variety were sensitive to photoperiod, thus, how Taichung 65 loss its sensitivity is a mystery. In this study, we used accession-specific single nucleotide polymorphism analysis to reveal the gene flow that occurred between different rice accessions decades ago and demonstrate that two landraces introgressed during the breeding process, which led to the loss of photoperiod sensitivity. Both Hd1 and Ehd1 may be important during artificial selection for flowering time, especially in a subtropical region such as Taiwan. This is a good example of introgression playing important roles during rice domestication.
水稻是一种兼性短日植物，它需要短于临界日长的光周期才能开花。对光周期的敏感性被认为是栽培稻或杂草稻的主要选择目标。台湾的现代水稻品种可能一年种植两次。这些品种包含两个重要开花时间相关基因 Heading date 1 (Hd1) 和 Early heading date 1 (Ehd1) 的功能丧失突变，主要来自一个巨型品种 Taichung 65。然而，这个品种的亲本对光周期很敏感，因此 Taichung 65 如何失去敏感性是一个谜。在这项研究中，我们使用特定于品系的单核苷酸多态性分析来揭示几十年前不同水稻品系之间发生的基因流，并证明在育种过程中，两个地方品种发生了基因渗入，导致对光周期敏感性的丧失。Hd1 和 Ehd1 都可能在人工选择开花时间中很重要，特别是在像台湾这样的亚热带地区。这是一个很好的例子，说明基因渗入在水稻驯化过程中发挥了重要作用。
