Paternal inheritance of chloroplast DNA and maternal inheritance of mitochondrial DNA in the genus Actinidia

PCR ampliÞcation of four chloroplast DNA (cpDNA) and two mitochondrial DNA (mtDNA) regions followed by restriction of the ampliÞed products was used to identify restriction fragment length polymorphisms in 21 Actinidia taxa. Subsequently, the mode of organelle inheritance was investigated in both interspeciÞc and intraspeciÞc controlled crosses made between genotypes showing di¤erent cpDNA and/or mtDNA haplotypes. Fifty-six seedlings produced from three interspeciÞc crosses, including in one case the pseudo reciprocal (di¤erent genotypes of the same species used as opposite parents), were checked for cpDNA inheritance, and 102 seedlings from the same interspeciÞc crosses and 32 seedlings from two intraspeci Þc crosses within the species A. deliciosa were checked for mtDNA inheritance. In all cases, cpDNA was inherited from the father and mtDNA was inherited from the mother. Maternal inheritance of mtDNA was expected, being the rule in plants, but A. deliciosa is the Þrst genus in angiosperms for which a widespread and strictly paternal inheritance of cpDNA has been reported. Transmission of chloroplastic and mitochondrial genomes through opposite parents provides an exceptional opportunity for studying the paternal and maternal genetic lineages of species in the genus Actinidia.