GENETIC-VARIABILITY AT THE GLU-1 LOCI IN OLD AND MODERN WHEATS (TRITICUM-AESTIVUM L) CULTIVATED IN SLOVAKIA

The high molecular weight glutenin subunits (HMW-GS) composition at th e Glu-l complex loci, in 23 old original wheat genotypes cultivated in Slovakia several decades ago and 32 modern Slovak and Czech wheat cul tivars growed in Slovakia at present were studied by SDS-PAGE. Some of the HMW-GS - subunit pairs 3+12, 17+18, and subunit 20, present in ol d ''historical'' wheats were missing in modern cultivars utilized in S lovakia nowadays. There were observed 15 different HMW-GS encoded by 1 1 alleles or allelic pairs in old genotypes. Lower number of different HMW-GS and competent alleles were observed in a set of modern wheat c ultivars - 11 different HMW glutenin subunits encoded by 8 alleles or allelic pairs. The same number of different HMW-GS patterns was reveal ed in both sets of wheats. From the point of view of genetic variabili ty, it could be concluded that long-term effort of breeders and decrea sing of cultivation of landraces and old cultivars are associated with the loss of several HMW-GS alleles and decreasing of genetic variabil ity of wheats. Molecular characterization can reveal broad allelic var iability of old wheat genotypes and landraces. Their maintenance in ge netic resource collections can prevent losses of these interesting gen es.