Genetic instability of a progeny from a somatic hybrid between tomato (Lycopersicon esculentum) and L. peruvianum

Abstract Some morphological characteristics of a progeny (H2) derived from a somatic hybrid (H1: 2 P n = 4x = 48) between tomato ‘Ponderosa’ and L. peruvianum were investigated to determine the genetic stability. The H2 progeny possessed morphological characteristics that were either similar to one fusion parent, intermediate between those of the two fusion parents, or that were unique. Some morphological characteristics in the H2 progeny were quite variable between the individual plants. Chromosome numbers of H2 progeny, pollen mother cells of H1, and hybridization patterns of ribosomal RNA gene (rDNA) of H2 progeny were investigated to elucidate the main causes of the morphological variations observed in the H2 progeny. From the results, it is suggested that the presence of aneuploid and chromosome pairing, including autosyndesis in the H1, were the main causes of morphological variations in individuals in the H2 progeny.