Tight Linkage between the Fin Locus for Plant Habit and the Z Locus for Partly Colored Seedcoat Patterns in Common Bean

Abstract

Linkage between the Fin locus controlling plant habit and the Z locus controlling partly colored seedcoats in common bean (Phaseolus vulgaris L.) was studied in the F2 and F3 progenies from the cross `t virgarcus BC3 5-593' (determinate habit, virgarcus pattern of partly colored seeds, fin tz) × `Steuben Yellow Eye' (indeterminate habit, sellatus pattern of partly colored seeds, Fin t zsel). The heterozygous genotype zsel/z produces the piebald pattern of partly colored seeds, whereas Fin is completely dominate to fin. Selection was made in the F2 for crossover phenotypes: indeterminate habit with virgarcus seeds or determinate habit with piebald seeds. Linkage calculations were based on crossover genotypes confirmed by F3 progeny tests grown in the greenhouse. The recombination percentage between Fin and Z was 1.032±0.33 map units. The gene symbol zsel is proposed, where t Z gives the expansa partly colored seedcoat pattern, t zsel gives sellatus, and t z gives virgarcus.