SOMATIC HYBRIDISATION BETWEEN PELARGONIUM x HORTORUM AND P. x DOMESTICUM TOWARDS RESISTANCE TO XANTHOMONAS PELARGONII

Sexual crossing between Pelargonium x hortorum (susceptible to Xanthomonas hortorum pv. pelargonii Xhp) and P. x domesticum (resistant) never succeeded.
Therefore somatic hybridisation were attempted.
Protoplast fusions were carried out using a polyethylene-based mass fusion protocol.
Putative somatic hybrid recovering was based on hybrid vigor, and on resistance to Xhp culture filtrate.
Fusion experiments yielded a high number of putative hybrid calli.
More than 1000 of them were induced to regenerate.
Until now eleven shoots were rooted in vitro and 6 were successfully acclimatized in the greenhouse.
Their hybrid status was evaluated (AFLP, flow cytometry, chromosome counting). Fifty percent of putative hybrid calli displayed resistance to Xhp. culture filtrate.