分子标记辅助选择改良玉米自交系昌7-2的丝黑穗病抗性

选取5个与bin2.09主效抗病位点紧密连锁的分子标记,利用含主效抗病位点的黄早四近等基因系1JD006为供体亲本,开展连续回交分子标记辅助选择育种,定向改良玉米自交系昌7-2的丝黑穗病抗性.结果表明,标记3M1-25选择效率最高,其次为标记MZA6393.结合分子标记辅助选择和田间接种鉴定,在BC2F2群体中筛选出背...

Improving Head Smut Resistance in Maize Inbred Line Chang7-2 by Marker Assisted Selection

Five molecular markers closely linked to major resistance loci of head smut in bin2.09 area, were used in this study including 3 STS markers and 2 dCAPS markers. The resistant near-isogenic line 1JD006, which was developed from the susceptible line Huangzao4 and the resistant line Mo17 carrying the major resistance QTL, was used as the resistant donor to improve the susceptible line Chang7-2 combing the marker assistant selection and backcross breeding method. The results showed that 3M1-25 was the optimal molecular marker with the highest selection efficiency, and next was marker MZA6393. Six plants with high background recovery rates(>87.5%) in BC2F2 population were selected. Twelve plants were selected from BC3F2 population with the recovery rates above 96.92%. The field incidence of them were below 40%. Except line 4JZ574-01, the main agronomic traits of the other lines in BC3F3 population were similar to Chang7-2.