Morphology, inheritance and mapping of a compressed lamina mutant of carrot

A compressed lamina mutant at a locus named COLA was selected in an inbred population of the cultivated carrot Daucus carota sativus Hoffm. Whereas segregation analyses of F 2 progenies, as well as corresponding F 3 families, indicated a monogenic recessive inheritance, detailed morphological and histological analyses revealed pleiotropic effects of the COLA gene. The mutant plants exhibited a semi-dwarf phenotype, shortened epidermal and leaf parenchyma cells and significantly reduced lamina dimensions. Furthermore, the mutant developed stipules and hypogynous flowers, contrary to the stipule-less leaves and epigynous flowers of the wild type. Using bulked segregant analyses, thirty-nine marker candidates were detected using 180 RAPD primer and 56 AFLP primer pairs. Twelve primers were linked to the COLA locus and mapped in a linkage group with a total length of 44.2 cM. Potential application of the compressed lamina mutant in carrot research is discussed.