Establishing self-incompatibility genotypes of several apple cultivars analyzing progenies derived by back-crossing

Abstract

The self-incompatibility genotypes of the parents, 'Golden Delicious' (GD), 'Jonathan' (J) and 'Fuji' (F) were established by analyzing the F2 progenies of 'Hatsuaki' (J x GD) and 'Iwakami' (F x J) derived by back-crossing the F1, 'Hatsuaki' (H) and 'Iwakami' (I) to their respective parental cultivars. That is, the F2 progenies from H x J, J x H, H x GD and GD x H were back-crossed to J and GD and those from F x I, I x J and J x I were back-crossed to F and I. The segregation ratio of compatible to incompatible plants was estimated. Among the 'Hatsuaki' progenies, the segregation ratio of compatible to incompatible from (H x J) x J and (H and GD) x GD was estimated at 1:1, (other 6 combinations were (1:0). In the 'Iwakami' progenies, those of (F x I), x J (I x J) x F, (I x J) x J, and (J x I) x F were estimated at 1:1, (other 2 combinations were 1:0). These results suggest that Jonathan' has no common S-allele with 'Golden Delicious', and 'Fuji' has one common S-allele with 'Jonathan'.