Tagging of the restorer gene for rice HL-type CMS using microsatellite markers

30.Tagging of the restorer gene for rice HL-type CMS using microsatellite markers Q. HUANG1.2, Y. HE�, R. Jin1, H. Huang1 and Y. Zhu1 1) College of Life Sciences, Wuhan University, Wuhan 430072, China 2) College of Life Sciences, Central China Normal University, Wuhan 430079, China Cytoplasmic male sterility (CMS) is the commonly used system in hybrid rice breeding. There are three main CMS sources, that is WA, BT and HL popularly used in commercial hybrid rice seed production. Location of the restorer genes for CMS lines with DNA markers has been investigated during the last few years. The restorer gene for the BT-type CMS, Rf-1, has been mapped to chromosome 10 (Akagi et a!. 1996; Ichikawa et al. 1997). However, reports regarding the locations of restorer genes for the WA-type CMS are inconsistent. Seven chromosomal locations have been reported: two on chromosome 1 (Zhang eta!. 1997; Yao eta!. 1997; Shen et a!. 1998), one on chromosome 7 (Bharaj eta!. 1995), two on chromosome 10 (Bharaj et al. 1995; Yao eta!. 1997; Tan et al. 1998), and four QTLs on chromosome 2, 3,4 and 5 (Zhu et a!. 1996). Our study on the inheritance of fertility restoration of FIL-type CMS indicated that a single dominant gene controlled the trait (Huang et a!. 1998). We determined the location of this restorer gene using microsatellite markers. The BC, population derived from Congguang 4lAJIMiyang 23/Congguang 41B was used for mapping this restorer gene. Pollen fertility was recorded at flowering time. The segregation of fertile plants (Rfrf) and sterile plants (rfrJ) in this population was in the ratio of 1:1. Bulked DNA segregant analysis using microsatellites was used to identify DNA markers associated with the restorer gene. One hundred and fifty-nine microsatellite primers were screened for polymorphism between the parents and between two bulks representing fertile and sterile plants. One microsatellite primer RM258 produced polymorphic products (Fig. 1). The microsatellite primer RM258 was then used to survey the BC, population. Amongst seventy-five fertile plants eight plants were recombinant and amongst ninety-eight sterile plants five plants were recombinant. The linkage analysis with Mapmaker 3.0 revealed that the restorer gene was linked to RM258. The genetic distance between them was 7.8cM. Therefore, the restorer gene for the HL-type CMS designated as Rf-5, was located on chromosome 10. It is noteworthy that Rf-1 and Rf-4, the restorer genes of WA-type CMS were also located in the adjacent region on chromosome 10. We postulated that Rf-5 and Rf-4 are tightly linked, while Rf-5 and Rf-1 are allelic. Further studies are needed to clarify the relationships among three restorer genes. References Akagi, H., Y. Yokozeki, A. Inagaki, A. Nakamura and T. Fujimura, 1996. A codominant DNA marker closely linked to the rice nuclear gene, Rf-1, identified with inter-SSR fingerprinting. Genome 39: 1205-1209. Bharaj, T.S., S.S. Virmani and G.S. Khush, 1995. Chromosome location of fertility restoring genes for �wild abortive� cytoplasmic male sterility using primary trisomics in rice. Euphytica 83: 169-173. Huang, Q., Y.Q. He and Y.G. Zhu, 1998. Genetics of fertility restoration of �HL� type cytoplasmic male sterility in rice (Oryza saliva L.). ABSTRACTS of 18th Intl. Congress of Genetics, p. 273. Ichikawa, N., N. Kishimoto,A. Inagaki, A. Nakamura, Y. Koshino, Y. Yokozeki, M. Oka, S. Samoto, H. Akagi, K. Higo, Ch. Sbinjyo, T. Fujimura and H. Shimada, 1997. A rapid PCR-aided selection of a rice line containing the Rf-1 gene which is involved in restoration of the cytoplasmic male sterility. Mol. Breed. 3: 195-202. Shen, Y., Z.Q. Guang, J. Lu, .LY. Zhuang, K.L. Zheng, MW. Gao and X.M. Wang, 1998. Linkage analysis of a fertility restoring mutant generated form CMS rice. Theor. Appi. Genet. 97: 261-266. Tan, X.L., A. Vanavichit, S. Amornsilpa and S. Trangoorung, 1998. Genetic analysis of rice CMS-WA fertility restoration based on QTL mapping. Theor. Appl. Genet. 97:994-999. Yao, F.Y., C.G. Xu, S.B. Yu,J.X. Li, Y.J. Gao, X.H. Li and Q. Zhang, 1997. Mapping and genetic analysis of two fertility restorer loci in the wild-abortive cytoplasmic male sterility system of rice (Oryza sativa L.). Euphytica 98: 183-187. Zhang, 0., T.S. Bharaj, S.S. Virmani and N. Huang, 1997. Mapping of the Rf-3 nuclear fertility restoring gene for WA cytoplasmic male sterility in rice using RAPD and RFLP markers. Theor. App!. Genet. 94: 27- 33. Zhu, L., C. Lu, P. Li, L. Shen, Y. Xu, P. He andY. Chen, 1996. Using doubled haploid populations of rice for quantitative trait locus mapping. Rice Genetics Ill, p. 631-634. IRRI, Manila, Philippines.

30.Tagging of the restorer gene for rice HL-type CMS using microsatellite markers
Q. HUANG1.2, Y. HE�, R. Jin1, H. Huang1 and Y. Zhu1

1) College of Life Sciences, Wuhan University, Wuhan 430072, China

2) College of Life Sciences, Central China Normal University, Wuhan 430079, China

Cytoplasmic male sterility (CMS) is the commonly used system in hybrid rice breeding. There are three main CMS sources, that is WA, BT and HL popularly used in commercial hybrid rice seed production. Location of the restorer genes for CMS lines with DNA markers has been investigated during the last few years. The restorer gene for the BT-type CMS, Rf-1, has been mapped to chromosome 10 (Akagi et a!. 1996; Ichikawa et al. 1997). However, reports regarding the locations of restorer genes for the WA-type CMS are inconsistent. Seven chromosomal locations have been reported: two on chromosome 1 (Zhang eta!. 1997; Yao eta!. 1997; Shen et a!. 1998), one on chromosome 7 (Bharaj eta!. 1995), two on chromosome 10 (Bharaj et al. 1995; Yao eta!. 1997; Tan et al. 1998), and four QTLs on chromosome 2, 3,4 and 5 (Zhu et a!. 1996). Our study on the inheritance of fertility restoration of FIL-type CMS indicated that a single dominant gene controlled the trait (Huang et a!. 1998). We determined the location of this restorer gene using microsatellite markers.

Bulked DNA segregant analysis using microsatellites was used to identify DNA markers associated with the restorer gene. One hundred and fifty-nine microsatellite primers were screened for polymorphism between the parents and between two bulks representing fertile and sterile plants. One microsatellite primer RM258 produced polymorphic products (Fig. 1). The microsatellite primer RM258 was then used to survey the BC, population. Amongst seventy-five fertile plants eight plants were recombinant and amongst ninety-eight sterile plants five plants were recombinant. The linkage analysis with Mapmaker 3.0 revealed that the restorer gene was linked to RM258. The genetic distance between them was 7.8cM. Therefore, the restorer gene for the HL-type CMS designated as Rf-5, was located on chromosome 10.

It is noteworthy that Rf-1 and Rf-4, the restorer genes of WA-type CMS were also located in the adjacent region on chromosome 10. We postulated that Rf-5 and Rf-4 are tightly linked, while Rf-5 and Rf-1 are allelic. Further studies are needed to clarify the relationships among three restorer genes.

References

Akagi, H., Y. Yokozeki, A. Inagaki, A. Nakamura and T. Fujimura, 1996. A codominant DNA marker closely linked to the rice nuclear gene, Rf-1, identified with inter-SSR fingerprinting. Genome 39: 1205-1209.

Bharaj, T.S., S.S. Virmani and G.S. Khush, 1995. Chromosome location of fertility restoring genes for �wild abortive� cytoplasmic male sterility using primary trisomics in rice. Euphytica 83: 169-173.

Huang, Q., Y.Q. He and Y.G. Zhu, 1998. Genetics of fertility restoration of �HL� type cytoplasmic male sterility in rice (Oryza saliva L.). ABSTRACTS of 18th Intl. Congress of Genetics, p. 273.

Ichikawa, N., N. Kishimoto,A. Inagaki, A. Nakamura, Y. Koshino, Y. Yokozeki, M. Oka, S. Samoto, H. Akagi, K. Higo, Ch. Sbinjyo, T. Fujimura and H. Shimada, 1997. A rapid PCR-aided selection of a rice line containing the Rf-1 gene which is involved in restoration of the cytoplasmic male sterility. Mol. Breed. 3:

195-202.

Shen, Y., Z.Q. Guang, J. Lu, .LY. Zhuang, K.L. Zheng, MW. Gao and X.M. Wang, 1998. Linkage analysis of a fertility restoring mutant generated form CMS rice. Theor. Appi. Genet. 97: 261-266.

Tan, X.L., A. Vanavichit, S. Amornsilpa and S. Trangoorung, 1998. Genetic analysis of rice CMS-WA fertility restoration based on QTL mapping. Theor. Appl. Genet. 97:994-999.

Yao, F.Y., C.G. Xu, S.B. Yu,J.X. Li, Y.J. Gao, X.H. Li and Q. Zhang, 1997. Mapping and genetic analysis of two fertility restorer loci in the wild-abortive cytoplasmic male sterility system of rice (Oryza sativa L.). Euphytica 98: 183-187.

Zhang, 0., T.S. Bharaj, S.S. Virmani and N. Huang, 1997. Mapping of the Rf-3 nuclear fertility restoring gene for WA cytoplasmic male sterility in rice using RAPD and RFLP markers. Theor. App!. Genet. 94: 27-

33.

Zhu, L., C. Lu, P. Li, L. Shen, Y. Xu, P. He andY. Chen, 1996. Using doubled haploid populations of rice for quantitative trait locus mapping. Rice Genetics Ill, p. 631-634. IRRI, Manila, Philippines.