Unequal Segregation of Nuclear Genes in Plants

Abstract

The proportion of loci deviating from the expected monogenic segregation ratios in the genera Lens. Capsicum, and Lycopersicon is significantly higher (61/114 genes, 54%) for progeny of interspecific hybrids than for progeny of intraspecific hybrids (7/52 genes, 13%). Although aberrant segregations are expected to be more common in progeny of interspecific hybrids, this is the first estimate of the magnitude of this phenomenon, based on a random sample of genes in a number of plant genera. We interpret these unequal segregations as the result of linkage between the markers and gene(s) that operate in pre- and postzygotic phases of reproduction. Such unequal segregations should be considered in planning breeding programs.