Biparental plastid inheritance in Oenothera organensis Munz

In an article on the ultrastructure of pollen grains of Oenothera organensis (Cresti et al. 1983) the authors state in the discussion (last paragraph) that “the present investigation documents an evidence of non-production of mixed cells having egg and sperm plastids side by side, even after successful fertilization so that the uniparental plastom-genome interaction is likely to maintain the characteristics of this S3S4 genotype...”. If these observations are correct, the strain investigated represents an exception in the species Oe. organensis. Our hybridization experiments with Oe. organensis and species of subsection Oenothera (Euoenothera) clearly document biparental plastid transmission also in Oe. organensis. We were able to produce hybrids between several species of Euoenothera as seed parent and Oe. organensis (subsection Emersonia) as pollen parent (Stubbe & Raven 1979). By backcrossing with Oe. organensis variegated progeny with the genotype of Oe. organensis have been established, in which the maternal plastids of Euoenothera species are pale while the paternal plastids of Oe. organensis are green.