Caipira sweet orange + Rangpur lime: a somatic hybrid with potential for use as rootstock in the Brazilian citrus industry

protoplast culture following polyethylene glycol-induced fusion resulted in the regeneration of somatic hybrid plants between caipira sweet orange (citrus sinensis l. osbeck) and rangpur lime (c. limonia l. osbeck). the plants were confirmed as somatic hybrids by leaf morphology, chromosome number and rapd profile. all regenerated plants were tetraploid (2n = 4x = 36), with intermediate leaf morphology and complementary rapd banding profile of both parents. this combination may be useful as a rootstock for the citrus industry in southeastern brazil since this somatic hybrid could combine the drought tolerance and vigor of rangpur lime with the blight tolerance of caipira sweet orange.