谷子抽穗期突变体jt1242-14b的遗传分析和定位

为鉴定控制谷子抽穗的关键基因,通过甲基磺酸乙酯(ethyl methyl sulfonate,EMS)诱变谷子参考基因组测序品种豫谷1号,获得遗传稳定的谷子超早抽穗突变体jt1242-14b.与豫谷1号相比,jt1242-14b抽穗期明显提前,茎秆变细,叶片变窄、变短.遗传分析表明,突变性状受隐性单基因控制.以SSR41(父本)、jt1242-14b(母本)和F₂群体进行突变基因定位,结果表明,该基因位于第9号染色体,在分子标记In4746和In9-11之间的4 447 kb之内.进一步测序比对分析发现突变位点位于PHYB基因内部,因此,PHYB很可能是该早熟突变体的目标基因.本研究为谷子早抽穗基因克隆及PHYB基因功能研究提供材料基础.

Genetic analysis and mapping of a heading date mutant jt1242-14b in Setaria italica

To identify the target genes controlling heading date, an early heading mutant jt1242-14b was identified from the ethyl methyl sulfonate(EMS)induced mutant library of the foxtail millet variety Yugu1. Compared with Yugu1, jt1242-14b showed an early heading date, thinner stem, and narrow and short leaves. Genetic analysis showed that the mutant was controlled by a recessive gene. Genetic mapping of the mutant gene was conducted from segregating population of jt1242-14b/SSR41. The gene was mapped in an interval of 4 447 kb between the molecular marker In4746 and In9-11 on chromosome 9. Finally, jt1242-14b was caused by a mutation in PHYB gene revealed by sequencing, so PHYB could be the target gene of the early heading mutant. This study provided a material foundation for cloning and functional research of PHYB in millet early heading genes.