[Contributions to the problem of plastid change : V. Another(35)S-induced nuclear gene mutant effecting plastid...

Seeds ofEpilobium hirsutum were treated with 0.5 mC(35)S isotope. One treated plant gave rise to variegated plants when selfed. Crosses revealed that this was caused by a recessive gene mp2 which induces plastid mutations.That the observed variegation was due to mutations of the plastids could be derived from the evidence of the characteristic patterns of the leaves and from the occurrence of actual mixed cells. Maternal inheritance of the mutated plastids could not be demonstrated as the mp2 gene induces most of the plastid mutations too late in the development of the leaves to exert an effect on the shoots and cell lines giving rise to egg cells.