Dwarfing genes in the genus Lens Mill.

Dwarfing genes were detected following intra- and interspecific hybridization in Lens. Dwarf phenotypes are controlled by two complementary dominant genes, Df₁ and Df₂. These two genes are suppressed by the dominant allele of the dwarf inhibitor genes, Dfi. The dominant allele of the Df gene was detected in L. ervoides from Ethiopia and Uganda and in a cultivated line of L. culinaris from Ethiopia, that of the Df₂ gene in a L. ervoides accession from Israel. The dominant allele of the Dfi gene was detected in segregating populations of hybrids between L. ervoides accessions from Israel and Uganda. Using the homozygous dwarf, dfidfi, Df₁Df₁, Df₂Df₂ as the parent in interspecific crosses, we detected the dominant allele of the Dfi gene in one accession of L. nigricans and another of L. lamottei. The appearance of dwarf plants in segregating populations of hybrids between the cultivated line from Ethiopia and L. ervoides from Israel indicate that the cultivated line possesses the dominant allele of the Dfi gene. Dwarf plants were characterized by short internodes, a short leaf axis and smaller, convex leaflets. Spraying the dwarf plants with gibberellic acid induced internode and lead-axis elongation but had no effect on leaflet shape and size. When the dwarfs and their parental lines were grown in the dark they had the same internode length.