Isozyme Polymorphism in Lens (Leguminosae)

Crossability and cytological studies have led to a recent taxonomic revision of Lens. Starch gel electrophoresis of isozymes was employed to clarify the relationships among the revised Lens taxa and provide further insight as to the origin of the cultivated lentil, L. culinaris ssp. culinaris. The 14 enzymes studied yielded scorable products of 25 putative isozyme loci, 16 of which were polymorphic. Isozyme polymorphism within accessions was extremely low while greater amounts of variation were observed among accessions and even greater amounts among taxa. A high degree of electrophoretic similarity was found among L. culinaris ssp. culinaris, L. culinaris ssp. orientalis, and L. culinaris ssp. odemensis. Lens nigricans ssp. ervoides possessed more allozymes in common with all three L. culinaris subspecies than with L. nigricans ssp. nigricans. Similarly, a differentiated cytotype of ssp. nigricans showed more electrophoretic affinity with all three L. culinaris subspecies and ssp. ervoides than with the remaining accessions of ssp. nigricans which emerged as the most electro- phoretically distinct group. On the basis of the electrophoretic data alone, ssp. orientalis and ssp. odemensis are the most likely progenitors of the cultivated lentil, ssp. culinaris.