Novel Phaseolin types in wild and cultivated common bean (Phaseolus vulgaris, Fabaceae)

Abstract

Forty-one wild types and 41 cultivars of common bean (Phaseolus vulgaris) from Meso-and South America were screened for variability of phaseolin seed protein using one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE) and two-dimensional isoelectric focusing SDS/PAGE. Wild accessions from the Andean region showed phaseolin types which had not been previously identified in wild material from that region. Other wild accessions from Argentina exhibited novel phaseolin patterns collectively designated as ‘J’ (‘Jujuy’) phaseolin types, and one accession from northern Peru exhibited a novel phaseolin type, the ‘I’ (‘Inca’) type. The ‘H’ and ‘C’ phaseolins, previously identified only in cultivars, were observed in several wild accessions from Argentina. Among cultivars, two minor variants of the ‘S’ phaseolin type were identified. The ‘Sb’ (‘S Brazil’) was characteristic of a limited number of cultivars from Brazil whereas the ‘Sd’ (‘S Durango 222’) predominated in cultivars of the Mexican central highlands. The distribution of the previously described ‘B’ phaseolin appeared to be larger than formerly known as it extended not only in Colombia but also in Central America. It is possible to correlate the ‘Sb’, ‘Sd’, and ‘B’ phaseolin types with certain agronomic traits.