Abstract: To generate seedless triploidswith horticulturally acceptable fruit, interploidy crosses between elite allotetraploid somatic hybrids and several diploid cultivars were conducted in 2001 and 2002. Tetraploid somatic hybrids such as NS ( Tangelo + Sweet orange) , NH (Tangelo +HB pummelo) , SH ( Sweet orange + HB pummelo) , VM (Valencia orange + Tangor) , HD ( Sweet orange + Tangerine) were selected as male parents, and dip loid cultivars i1e. Shatian pummelo, Huanong Bendizao tangerine, Zhongqiu Satsuma, HB pummelo, Guoqing 4 satsuma were used as female parents. By embryo rescue technique, a total of 244 triploid and 10 tetrap loid p lantswere verified by flow cytometry analysis and chromosome counting from 10 crosses in 2001 and 2002. Out of these triploids, 147 were from the cross of Shatian pummelo as the female parent. So far, 172 trip loid and 4 tetrapliod plants have been transplanted and survived in greenhouse and field.

Key words: Citrus, Triploid, Seedlessness, Embryo rescue, Flow cytometry