title: Effects of Hd2 in the presence of the photoperiod-insensitive functional allele of Hd1 in rice.
abstract: The role of photoperiod sensitivity (PS) of flowering genes have become well recognized in rice, whereas little attention has been drawn to the non-PS component of these genes, especially to their influence on gene-by-gene interactions. Rice populations in which the photoperiod-sensitive allele at Hd1 has become insensitive to photoperiod but continued to affect heading date (HD) were used in this study to fine-map a quantitative trait locus (QTL) for HD and analyze its genetic relationship to Hd1 The QTL was delimitated to a 96.3-kb region on the distal end of the long arm of chromosome 7. Sequence comparison revealed that this QTL is identical to Hd2 In the near-isogenic line (NIL) populations analyzed, Hd1 and Hd2 were shown to be photoperiod insensitive and have pleiotropic effects for HD, plant height and yield traits. The two genes were found to largely act additively in regulating HD and yield traits. The results indicate that non-PS components of flowering genes involved in photoperiod response play an important role in controlling flowering time and grain yield in rice, which should allow breeders to better manipulate pleiotropic genes for balancing adaptability and high-yielding accumulation.
authors: State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006, China.
authors: Zhen-Hua
authors: ZH
authors: Zhang
authors: State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006, China.
authors: Li-Yong
authors: LY
authors: Cao
authors: State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006, China.
authors: Jun-Yu
authors: JY
authors: Chen
authors: State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006, China.
authors: Ying-Xin
authors: YX
authors: Zhang
authors: State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006, China zhuangjieyun@caas.cn chengshihua@caas.cn.
authors: Jie-Yun
authors: http://orcid.org/0000-0002-1439-5061
authors: JY
authors: Zhuang
authors: State Key Laboratory of Rice Biology and Chinese National Center for Rice Improvement, China National Rice Research Institute, Hangzhou 310006, China zhuangjieyun@caas.cn chengshihua@caas.cn.
authors: Shi-Hua
authors: SH
authors: Cheng
keywords: Hd1; Hd2; Heading date; Photoperiod-insensitivity; Rice; Yield traits