Evaluation of somatic hybrids of potato with Solanum stenotomum after a long-term in vitro conservation

Abstract Somatic hybrids of potato with a cultivated relative, Solanum stenotomum also called Solanum tuberosum Stenotomum group, were evaluated for their physiological and agronomical characteristics as well as the stability of the introgressed resistance to bacterial wilt, caused by Ralstonia solanacearum , after a long-term in vitro conservation for more than 5 years. Analysis of photosynthesis showed that the PEPC/Rubisco ratio remained lower than 0.5 for all vitroplants of potato and the somatic hybrids, except for the relative species. This indicates that the carbon metabolism is heterotrophic (ratio > 1) for S. stenotomum , and autotrophic for potato and the somatic hybrids (ratio  S. stenotomum into potato, was shown to be very stable and remained as high as that of the relative after a long-term period of in vitro conservation.