TISSUE-CULTURE RESPONSE IN VARIOUS WILD AND CULTIVATED SOLANUM GERMPLASM ACCESSIONS FOR EXPLOITATION IN POTATO BREEDING

The response to different in vitro methods for use in potato breeding has been evaluated in 11 genotypes of 5 Solanum species, S. etuberosum , S. lycopersicoides, S, maglia, S. rickii, and S. tuberosum. Callus i nduction and growth, and shoot regeneration were strongly influenced b y the genotype, explant source, and medium utilized. Furthermore, cons iderable differences among the 11 genotypes were found both in plating efficiency and shoot regeneration from protoplast culture. Some inter esting correlations were found between different tissue culture respon ses, suggesting linkage and/or pleiotropic effect of genes. The potent ial application to potato breeding of the in vitro techniques analyzed is discussed.