Interspecific Hybridization and Aneuploidy in the Genus Nicotiana

Abstract

Three stable aneuploids 2n=80, 82, 84 were isolated from the colchiploid N. umbratica-megalosiphon. No morphological differences were detected between these aneuploids. Meiotic irregularities were recorded in the first few generations and reduced as the generations advanced. It was concluded that the phenotypic characters were fixed at the F₁ level itself and the addition of excess chromosomes to the F₁ complement had no visible effect on the phenotype. The above aneuploids support Goodspeed's postulate (1954).