The linkage map of the second chromosome of the tomato

Abstract

The map of chromosome 2 has been brought up to date and 33 genes are located. Three-point crosses indicate that the gene order is s ms10wv Wo Me o dil aw (v2op suf) p d m dv, with the relative order of the three genes in parentheses still to be determined. Multiple two-point crosses are reported for the other 18 genes whose linkage relationships to d, aw, and their nearest neighbor are discussed. This permits the construction of a map for these genes placing the 33 mutants in relation to the centromere. The gene dd seems to be wrongly located.The heterogeneity of some recombination values and the paucity of close linkages in the central portion of the chromosome reveal a number of problems which should be investigated. The chromosome map which has been largely constructed from material with a uniform background forms a reference point for investigating the effect of asynapsis and inversions.