Increasing crop yield is one of the most important goals of plant science research. Grain size is a major determinant of grain yield in cereals and is a target trait for both domestication and artificial breeding. We showed that the quantitative trait locus (QTL) GS5 in rice controls grain size by regulating grain width, filling and weight. GS5 encodes a putative serine carboxypeptidase and functions as a positive regulator of grain size, such that higher expression of GS5 is correlated with larger grain size. Sequencing of the promoter region in 51 rice accessions from a wide geographic range identified three haplotypes that seem to be associated with grain width. The results suggest that natural variation in GS5 contributes to grain size diversity in rice and may be useful in improving yield in rice and, potentially, other crops.
增加作物產(chǎn)量直是植物科學(xué)研究中最要的目標(biāo)之一。籽粒大小是決定谷類作物籽粒產(chǎn)量的主要決定因子，也是作物馴化和人工育種的目標(biāo)性狀。我們發(fā)現(xiàn)數(shù)量性狀基因GS5通過調(diào)控粒寬、充實度和粒重控制籽粒大小。GS5編碼一個預(yù)測的絲氨酸羧肽酶，正向調(diào)控籽粒大小，因此，GS5高表達具有更大的籽粒。通過對來自亞洲不同地區(qū)的51份水稻品系進行的GS5的啟動子測序，我們發(fā)現(xiàn)了它們的啟動子存在3種單倍型，這些單倍型與粒寬有關(guān)。以上結(jié)果表明水稻GS5基因的變異與水稻谷粒大小多樣性有關(guān)，該變異的發(fā)現(xiàn)有利于提高水稻產(chǎn)量，也可能對其他作物增產(chǎn)有幫助。