AUTHOR=Cui Yongxia , Wang Junrui , Feng Li , Liu Sha , Li Jiaqi , Qiao Weihua , Song Yue , Zhang Zongqiong , Cheng Yunlian , Zhang Lifang , Zheng Xiaoming , Yang Qingwen 

TITLE=A Combination of Long-Day Suppressor Genes Contributes to the Northward Expansion of Rice

JOURNAL=Frontiers in Plant Science

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2020.00864

DOI=10.3389/fpls.2020.00864

ISSN=1664-462X

ABSTRACT=<p>Growing cultivated rice with a moderate heading date is the key to expanding its cultivation area and maintaining stable yields. The genes that regulate heading date are largely cloned; however, it remains unclear how genetic mutations and their combinations affect the heading date and adaptability of cultivated rice. Here, we report the analysis of genetic variation in eight long-day flowering suppressor genes (<italic>Hd1, DTH8, Ghd7, OsCOL4, DTH7, Hd6, Se5</italic>, and <italic>PhyB</italic>) and the phylogenetic relationship of eight genes. Genetic variations in <italic>DTH8</italic>, <italic>Ghd7</italic>, <italic>Hd1</italic>, <italic>DTH7</italic>, <italic>PhyB</italic>, and <italic>OsCOL4</italic> are correlated with differences in heading date and the correlation between the genetic diversity of <italic>Hd6</italic> and <italic>Se5</italic> and rice heading data are weak. One group of haplotypes of <italic>DTH8</italic>, <italic>Ghd7</italic>, <italic>Hd1</italic>, <italic>DTH7</italic>, <italic>PhyB</italic>, and <italic>OsCOL4</italic> are associated with earlier heading dates and appear to have accumulated during the northward expansion of rice cultivation. A minimum of four group A alleles of <italic>DTH8</italic>, <italic>Ghd7</italic>, <italic>Hd1</italic>, <italic>DTH7</italic>, <italic>PhyB</italic>, and <italic>OsCOL4</italic> are required for the growth of cultivated rice at latitudes above 30°N. This study presents a preliminary investigation of the genetic patterns and adaptation mechanisms of long-day flowering suppressor genes and provides a useful reference for the molecular breeding of rice cultivars for various environments and farming systems.</p>