Heritable variation in the phaseolin protein of nondomesticated common bean, Phaseolus vulgaris L.

Crude protein extracts from single seeds of nondomesticated Mexican bean accessions were analysed by SDS polyacrylamide gel electrophoresis for variability in phaseolin protein. Six new phaseolin types; 'M1', 'M2', 'M3', 'M4', 'M5', 'M6', which contained polypeptides within the same range of molecular weights (51,000 to 45,000 daltons) as occur in the 'S', 'T' and 'C' phaseolin types of cultivated beans were identified. No 'T' and 'C' types were found among the non-domesticated Mexican accessions, and the 'S' type occurred in less than 7% of the seeds screened. Genetic analyses of F2 progenies from crosses between 'Sanilac' ('S'), and five of the 'M' types showed that each 'M' phaseolin phenotype was allelic to the 'S' type and expressed codominantly.