VARIATION OF SEED STORAGE PROTEINS IN LANDRACES OF COMMON BEAN (PHASEOLUS-VULGARIS L) FROM BASILICATA, SOUTHERN ITALY

Twenty landraces of common bean (Phaseolus vulgaris L.) from Sarconi a nd Rotonda two locations of Basilicata, a Southern Italy region, were screened for variation in seed storage proteins (phaseolin and phytohe magglutinin) by polyacrylamide gel electrophoresis (SDS/PAGE and IEF-S DS/PAGE). No variation of the main seed protein fractions was observed within each landrace. Phaseolin patterns type C and T were exhibited from the landraces; the type C resulted predominant with a frequency o f 70%. Only the C type was observed for the landraces of Rotonda, T an d C for those from Sarconi. Two variants were observed for the phytohe magglutinin by SDS-PAGE, one was common to eighteen landraces. However , these variants submitted to IEF-SDS/PAGE resulted similar to the typ e T-G2 described by Brown. The importance to safeguard these landraces is stressed by the observation that the more spread commercial cultiv ars of common bean growing in Southern-Italy had a T phaseolin pattern . A reduction of C type diffusion could produce the loss a typical tra it of common bean in Mediterranean regions.