Sequence Polymorphism Analysis of Photoreceptor Genes in 19 Rice Landraces

Rice heading stage is mainly controlled by photoperiod pathway.The phytochromes and cryptochromes are the key photoreceptors sensing light and controlling flowering time in plants.During domestication,strong artificial selection formed a variety of landraces with different distribution and heading stage.To clarify the molecular basis for adaption of landraces to various environments,the sequence polymorphism of the coding regions of five photoreceptor genes,including OsPHYA,OsPHYB,OsCRY1 a,OsCRY1 b and OsCRY2 were analyzed in 19 landraces(11 Indica cultivars and 8 Japonica cultivars).The results showed that totally 23 nucleotide polymorphic sites were found,and 11 of them caused the changes of amino acid.OsPHYB and OsCRY2 had higher sequence polymorphism,which may be the key loci affecting rice heading stage in artificial selection.