一个新矮生玉米种质资源的发现与遗传鉴定

Discovery and Genetic Identification of a New Dwarf Germplasm in Maize

玉米矮生种质资源在育种工作中具有重要的利用价值。2002年在玉米种质资源扩繁与鉴定过程中,从玉米自交系K36中发现一株矮生突变体。随后通过连续自交,获得了纯合一致、稳定的矮生自交系,命名为矮2003。该矮秆材料在北京表现株高62.1cm,植株清秀,茎秆坚硬,结实正常。于不同时期用不同浓度赤霉素处理该材料显示其对赤霉素反应不敏感。矮2003与正常玉米自交系测交F1呈现高秆,F2与BC1高、矮秆分离比例分别符合3∶1与1∶1,遗传分析表明其矮生性状受一对主效单基因控制,表现为隐性遗传。所携带的矮生基因不同于已报道的玉米Dwarf8等。

Dwarf germplasm are valuable in breeding programs. We found a dwarf mutant from the inbred line K36 during multiplication in 2002. A stable inbred Ai 2003 was obtained after successive selfing. It was 62.1 cm in plant height with good agronomical performance in Beijing. The test for response to gibberellin （GA） in different stage and dosage showed that Ai 2003 was not sensitive to GA. In order to understand the genetic control of this dwarf material, several crosses between Ai 2003 and normal inbred lines were undertaken to produce F1, F2 or BC1 families. The results showed that this dwarf germplasm was controlled by a major single nuclear recessive gene, which was different from gene Dwarf8 （dominant） reported previously.