【摘要】 冈 4 6B(G4 6B)是水稻生产应用中的一个农艺性状十分优良的保持系 ,其主要的缺陷是稻瘟病抗性较弱 ,通过对地谷 ,BL 1,Pi 4号等三个分别含抗病基因Pi d(t) 1 、Pi b、Pi ta2 的稻瘟病抗性材料与G4 6B聚合杂交 ,并利用抗病基因连锁的分子标记对杂交后代进行辅助选择 ,在聚合杂交的F2代及B1C1代群体中共获得了 15株含Pi d(t) 1 、Pi b、Pi ta2 等三个抗稻瘟病基因的材料 ,其可能的基因型分别为 :三基因杂合体Pi d(t) 1 pi d(t) 1 Pi bpi b Pi ta2 pi ta2 4株 ,双基因杂合体 10株 ,其中Pi d(t) 1 Pi d(t) 1 Pi bpi b Pi ta2 pi ta2 6株 ,Pi d(t) 1 pi d(t) 1 Pi bpi b Pi ta2 Pi ta2 3株 ,Pi d(t) 1 pi d(t) 1 Pi bPi b Pi ta2 pi ta2 1株 ,双基因纯合体Pi d(t) 1 Pi d(t) 1 Pi bpi b Pi ta2 Pi ta2仅 1株 ,这一研究结果为进一步改良G4 6B的稻瘟病抗性奠定了基础 ,同时这一研究结果表明利用分子标记可快速、有效地实现多个抗病基因的聚合 ,大大提高水稻抗病育种的效率更多还原

【Abstract】 G46B is a promising holding line used for three lines breeding strategy in hybrid rice, but it is susceptible to blast disease caused by Pyricularia grisea. To improve its blast resistance, three rice varieties, Digu, BL 1, and Pi 4, with blast resistance genes, Pi d(t) 1, Pi b, and Pi ta 2, respectively, were used to be crossed with G46B, and 15 plants with these three blast resistance genes, Pi d(t) 1, Pi b, and Pi ta 2, were selected from their F2 and B1C1 populations via a marker aided crossing procedure. Among them, four plants were heterozygotes in the three resistance genes, with the genotype of Pi d(t) 1pi d(t) 1/Pi bpi b/ Pi ta 2pi ta 2; ten plants were heterozygotes in two of the three resistance genes, of which six with the genotype of Pi d(t) 1Pi d(t) 1/Pi bpi b/Pi ta 2pi ta 2, three with the genotype of Pi d(t) 1pi d(t) 1/Pi bpi b/Pi ta 2Pi ta 2, and one with the genotype of Pi d(t) 1pi d(t) 1/Pi bPi b/Pi ta 2pi ta 2; and only one plant was homozygote in two of the three resistance genes with the genotype of Pi d(t) 1Pi d(t) 1/Pi bpi b/Pi ta 2Pi ta 2 These results demonstrate the capacity of maker assisted selection (MAS) in gene pyramiding for rice blast resistance and its enhancement for the efficiency in rice resistance breeding.更多还原