The Journal of Heredity 1981:72(5):335-337
© 1981 The American Genetic Association 72:335-337
research-article |
Organelle transmission in higher plants: organelle alteration vs. physical exclusion
Southern Weed Science Laboratory, USDA-SEA-AR, Box 225 Stoneville, MS 38776
Abstract
Pelargonium x hortorum usually exhibits a biparental inheritance of plastid DNA although a severely debilitated plastome mutant of this species was not transmitted via the pollen. When the ultrastructure of pollen grains containing genetically mutant plastids was examined, the generative cell contained plastids and mitochondria, as did the generative cells containing wild-type plastids. Because the plastids are not physically excluded from the generative cell, although they are not transmitted via the pollen, the theory of physical exclusion is inadequate to explain the inheritance of plastids in this mutant. Mitochondria appear altered in pollen grains containing either wild-type or mutant plastids and are generally reduced to myelin-type figures at the last stages of degeneration. These data support the theory of organelle alteration as an explanation for the inheritance patterns of green and white plastids as well as the mitochondria in Pelargonium.