玉米抗粗缩病基因STS分子标记的筛选

对与玉米抗粗缩病相关基因共分离的RAPD标记S37和S86扩增的产物进行克隆与测序,设计多对引物,以感病自交系478和抗病自交系齐319、P138和H21为材料进行PCR扩增。结果表明:根据RAPD产物1300bp片段转化的STS引物在感病自交系中扩增出特异带,而在抗病自交系中无此特异PCR扩增带。根据2000bp片段转化的STS引物同样在抗感病自交系中存在特异性差异。进一步用设计的两对STS-PCR引物Ⅰ-2和Ⅱ-4对20个感病自交系和34个抗病自交系进行验证,卡方测验表明,STS标记Ⅰ-2和Ⅱ-4与自交系抗感病的相关性达到极显著水平。STS-PCR标记Ⅰ-2和Ⅱ-4可直接用于玉米抗粗缩病的分子标记辅助选择育种。

Development of STS-PCR Markers for Maize Rough Dwarf Virus Resistant Genes

Previous studies showed that RAPD markers S37 and S86 were co-segregated with MRDV resistance.S86 amplified a major product of 1300bp in size from susceptible line 478 and this specific product was absent from resistant lines Q319,P138 and H21.S37 amplified a major fragment of 2000bp in size from resistant lines and showed polymorphic from that amplified from susceptible line 478.We isolated and sequenced both the 1300bp and 2000bp DNA fragments and converted S37 and S86 into STS-PCR markers.The converted STS markers showed the same results as those of S37 and S86.These STS markers were further tested on 20 susceptible and 34 resistant lines.The Chi-Square test indicated the converted STS-PCR markers were significantly correlated with MRDV resistance.These stable and repeatable STS markers are of great interests to markers-assisted maize MRDV resistant variety development.