Griseofulvin-induced Chromosome Instability and Reduction in a Petunia Somatic Hybrid

Abstract

Abstract Leaf sections of a Petunia paradii x P. inflata somatic hybrid treated with griseofulvin (7-chloro-2’,4,6-trimethoxy-6’-methyl-spiro(benzofuran-2(3H), 1’-2 cyclohexene)-3, 4’dione) have been regenerated into whole plants. Of the regenerates, 5% expressed various degrees of leaf and flower abnormalities. About 80% of these abnormal types had chromosome numbers reduced from the pentaploid control level. It appears that the griseofulvin-induced chromosome instability may activate a type of position effect-variegation which causes both leaf and flower variegation.