HETEROGENEITY OF RECOMBINATION VALUES IN THE TOMATO

Abstract

The recombination values for a number of regions of the tomato chromosomes vary greatly. Often there are significant differences between coupling and repulsion values of F2 and backcross values. Detailed analyses of segregations involving large numbers of plants from various crosses which utilize parent stocks of diverse origin show heterogeneity of recombination values. The recombination values are associated with the parent stocks and probably are inherited in a polygenic manner. Some of the differences are large and several values are associated with the same region of the chromosome. For instance, the region d to aw had recombination values of 9%, 18%, 27%, and 36% in different crosses. Such large differences interfere with the successful mapping of chromosomes 2 and 10.