Identification of RAPD markers linked to the homostylar (Ho) gene in buckwheat

Aii, Jotaro¹, Nagano, Mio¹, Penner, Greg A.², Campbell, Clayton G.³ and Adachi, Taiji¹

¹ Applied Genetics and Biotechnology Division, Faculty of Agriculture, Miyazaki University, Gakuen Kibanadai Nishi, Miyazaki 889-2155, Japan, ² Agriculture and Agri-Food Canada, Winnipeg Research Station, 195 Dafoe Road, Winnipeg, Manitoba, R3T 2M9, Canada, ³ Kade Research Ltd. 135 13 Street, Morden, Manitoba, R6M 1E9, Canada.

Aii, Jotaro., Nagano, Mio., Penner , Greg. A., Campbell, Clayton G. and Adachi, Taiji. 1998. Identification of RAPD markers linked to the homostylar (Ho) gene in buckwheat. Breed. Sci. 48: 59-62.

Abstract: Common buckwheat, Fagopyrum esculentum, is a heteromorphic sporophytic self-incompatiblity species while an annual wild species, F. homotropicum, is homomorphic self-compatible. An F₂ population was generated from an interspecific hybrid between them and used to determine the genetic basis of self-compatibility due to homomorphic phenotype. Homostyly appears to be controlled by a single dominant gene (designated “Ho”) as F₂ progenies segregated in a 3 homomorphic : 1 heteromorphic flower types. We used RAPD and bulked segregate analysis to identify three markers, OPB14₁₂₅₀, OPP8₁₀₀₀ and OPQ7₈₀₀, linked to the Ho gene. All three markers were mapped to the same side of the Ho gene with OPB14₁₂₅₀ being the closest at 0.6cM. The mapping of this gene represents a first step toward better understanding of sexual reproduction system in buckwheat. These markers should be useful for marker-assisted selection for introgression of self-incompatibility into common buckwheat.

Key words: buckwheat, Fagopyrum esculentum, RAPD markers, homostylous, self-compatibility