[Marker-assisted selection and pyramiding for three blast resistance genes, Pi-d(t)1, Pi-b, Pi-ta2, in rice].
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), Pi-b, and Pi-ta2, 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-ta2, 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)1 pi-d(t)/Pi-b pi-b/ Pi-ta2 pi-ta2; ten plants were heterozygotes in two of the three resistance genes, of which six with the genotype of Pi-d(t)1 Pi-d(t)1/Pi-b pi-b/Pi-ta2 pi-ta2, three with the genotype of Pi-d(t)1 pi-d(t)1/Pi-b pi-b/Pi-ta2 Pi-ta2, and one with the genotype of Pi-d(t)1pi-d(t)1/Pi-b Pi-b/Pi-ta2 pi-ta2; and only one plant was homozygote in two of the three resistance genes with the genotype of Pi-d(t)1 Pi-d(t)/Pi-b pi-b/Pi-ta2 Pi-ta2. 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.
Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China. xwchen@genetics.ac.cn
Xue-Wei
XW
Chen
Shi-Gui
SG
Li
Yu-Qing
YQ
Ma
Han-Yun
HY
Li
Kai-Da
KD
Zhou
Li-Huang
LH
Zhu
D003433:Crosses, Genetic; D017343:Genes, Plant; D005819:Genetic Markers; D005838:Genotype; D012275:Oryza / Q000235:genetics*; D010935:Plant Diseases / Q000235:genetics*; D012641:Selection, Genetic
D005819:Genetic Markers