Induction and Genetic Identification of Embryogenic Calli from Hybrids of Shatian Pummelo

Shatian pummelo (Citrus grandis L. Osbeck cv. Shatian) is an elite variety in China, and the regeneration of the embryogenic callus is difficult. Diploid Shatian pummelo was used as the female and crossed with the allotetraploid somatic hybrid NS (Nova Tangelo + Succari Sweet orange), [(C reticulata Blanco × C. paradisi Macf.) cv. Nova + C sinensis L. Osbeck cv. Succari]. About 90 days after pollination, the embryos obtained from crosses were cultured on the solid media of MT + ME (malt extraction, 500 mg L−1) and MT + GA3 (1 mg L−1). The embryogenic callus was initiated from the embryoids and plantlets' hypocotyls and could be subcultured. Flow cytometry and SSR analysis verified that the callus was from the triploid hybrids. The callus had embryogenesis capacity and produced a large number of embryoids on MT + Lactose (50 g L−1) medium after being subcultured for two years. It is comparatively easier to obtain the callus from the hybrid embryo than from Shatian pummelo itself. The callus is valuable for the conservation and utilization of Shatian pummelo.