Production of hybrid calluses via donor-recipient fusion between Microcitrus papuana and Citrus sinensis

X-ray irradiated embryogenic protoplasts of Microcitrus papuana Swing. were electrically fused with iodoacetic acid-treated embryogenic protoplasts of Newhall navel orange Citrus sinensis (L.) Osb.]. Seven cell lines were established by low-melting agarose embedding culture of fusion-treated protoplasts. Cytological examination of 4 cell lines showed that each cell line consisted of many aneuploid (45.10%, 38.98%, 32.69% and 34.85%, respectively) and diploid cells (52.94%, 59.33%, 63.46% and 62.12%. respectively), whereas only a few tetraploid cells (1.96%, 1.69%, 3.85% and 3.03%, respectively) were detected. Analyses of random amplified polymorphic DNA with four 10-mer primers confirmed the hybrid characteristics of the cell lines, which in combination with chromosome counting proved that the cell lines were asymmetric hybrids. This revised version was published online in June 2006 with corrections to the Cover Date.