GENETIC-VARIABILITY OF CARROT SEED PROTEINS ANALYZED BY ONE-DIMENSIONAL AND 2-DIMENSIONAL ELECTROPHORESIS WITH IMMOBILIZED PH GRADIENTS

The genetic variability of eight carrot populations representing comme rcially important morphological types was analyzed for seed protein po lymorphism by one- and two-dimensional electrophoresis using immobiliz ed pH gradients (IPG) in order to assess the potential of both techniq ues in carrot hybrid breeding as well as genetic quality testing of ca rrot trade seeds. The digitized silver-stained one- and two-dimensiona l gels of the urea/detergent-soluble seed proteins were subjected to c omputer analysis to estimate both the inter- and intrapopulation genet ic variability The results indicated that isoelectric focusing (IEF-IP G) of seed proteins is a powerful tool for quick screening of the gene tic variability present between and within carrot populations, while t wo-dimensional polyacrylamide gel electrophoresis (IPG-DALT) can be em ployed to establish detailed genetic relationships of carrot populatio ns selected by initial IEF-IPG screening in order to use genetic dista nt and homogeneous populations for successful carrot hybrid breeding. However, the applicability of IEF-IPG in genetic quality testing of ca rrot seeds seems to be restricted to hybrid purity testing. IPG-DALT i s a far more powerful tool to profile unambiguously all carrot varieti es commercially used in order to test the genetic quality of trade see ds, because this technique exhibits protein spots or spot combinations exclusively found in each of the eight varieties investigated.