Nucleus substitution betweenPetuniaspecies using gamma ray-induced androgenesis

摘要

The ovaries of two differentPetuniaspecies:Petunia hybrida(hort) andPetunia parodii(Steere) were irradiated withτ-ray doses ranging from 50 to 1,000 Gy before pollination. Seed setting occurred after 4 days preculture on a non-sterile medium. Ovaries transformed into fruits were then cultivated aseptically with the following results: (1)τ-ray doses ranging from 200 to 1,000 Gy led to the development of two types of plants: haploids 2n=x=7 and overdiploids 2n>2x=14. (2) The androgenetic origin of haploids was ascertained by using genetic markers. The origin of overdiploids is discussed. (3) Androgenetic haploids contained the chloroplasts of the irradiated female parent. No visible change of cp DNA patterns was observed after irradiation. (4) The four possible androgenetic events were successfully obtained between the twoPetuniaspecies:hybridahaploids withhybridaorparodiicytoplasm, andparodiihaploids withparodiiorhybridacytoplas