Rice genetics watch: another grain size and yield gene

Shan et al. (2009) in Theoretical & Applied genetics report mapping of the gene spd6 which in wild O. rufipogon appeasr to reduced panicle size, grain number and grain size. This is likely to be yet another important gene that selection of early farming acted upon to increase yields (and grain sizes), along side genes such as qsw5, sw5, and gs3 that have been reported in recent years to affect grain size, and ghd7 and gn1a which affect p0anicle size and grain number. The new spd6 has been identified by a cross of a Hainan wild rice and the Chinese indica type, Teqing; it is not yet possible to draw any conclusions about the phylogenetic or geographical distributions of variants at this locus.