Heavy-ion-induced mutants in sweet pepper isolated by M1 plant selection

We examined the effects of heavy-ion bombardment on mutagenesis in sweet pepper (Capsicum annuum L.). Dose–response studies indicated that 10 Gy irradiation of ¹²C or ²⁰Ne ions on dry seeds is suitable for inducing mutations in plants. From ²⁰Ne-irradiated M₁ plants, putative mutants included two dwarf plants and one plant whose pericarp was yellow were isolated. Phenotypes of their M₂ progeny were similar to those of the M₁ plants and did not segregate. F₁ plants resulting from reciprocal crosses between the mutants and wild-type plants showed the wild-type phenotype, but phenotypes of F₂ and BC₁F₁ segregated at 1:3 (mutant:wild) and 1:1, respectively. These crossing experiments indicate that the three mutants have monogenic recessive mutations in nuclear genes. In light of these data, we discuss the effectiveness of using heavy-ion bombardment to mutate sweet peppers.