Regeneration of somatic hybrids of ginger via chemical protoplast fusion

Ginger (Zingiber officinale Rosc.) somatic hybridization was attempted by using polyethylene glycol (PEG)-mediated protoplast fusion. Protoplasts of three ginger cultivars isolated from the embryogenic cell suspensions were fused with each other. The highest binary fusion rate [13.5% in the fusion of ginger 'Lushan Zhangliang jiang' + 'Chenggu Huang Jiang' (LZ + CH)] was observed with the treatment of 30% PEG6000 for 15 min. The three fusion combinations can efficiently develop into micro-colonies and redifferentiate, but only the fusion of ginger 'Chenggu Huang Jiang' + 'Sichuan Zhugen Jiang' (CH + SZ) could regenerate plantlets. Approximately 15 months were used for the regeneration of whole plants, and 15 shoots were obtained from the fusion of LZ + CH. Three plantlets were identified as hybrids by using RAPD, and they were all diploids by analysis with flow cytometry.