Transmission of organelle genomes in citrus somatic hybrids

Restriction fragment length polymorphisms (RFLPs), were used to analyze the organelle composition of two-year-old trees, recovered from two different experiments: protoplasts from embryogenic cell suspensions of `Succari' swe et orange (C. sinensis L. Osbeck) were fused with leaf protoplasts of Citro psis gilletiana Swingle & M. Kell or to leaf protoplasts of Atalantia ceyla nica (Arn.) Oliv. The somatic hybrids of both fusion combinations had the m itochondrial genome from the embryogenic partner. In some somatic hybrids, non-parental fragments were observed among the mitochondrial patterns. Soma tic hybrids between `Succari' + Atalantia had plastid DNA from the embryoge nic parent, while the somatic hybrids of `Succari' + Citropsis all had both parental chloroplast genomes. The relative abundance of organelle DNAs in the donor embryogenic and leaf cells may explain the consistent transmissio n of the embryogenic parent mitochondrial DNA and the inheritance of the ch loroplast genome from either parent.