Tetrahaploids from colchicine-induced octaploid Solanum acaule subsp. Aemulans

Summary Crosses between colchicine-induced octaploid Solanum acaule ssp. aemulans (2n=8x =96) with diploid S. tuberosum, Group Phureja, carrying a homozygous embryo marker, produced a high percentage of S. acaule tetrahaploids besides pentaploid and hexaploid F₁ hybrids. These results are discussed in relation to the behaviour of autopolyploid and allopolyploid Solanum species, which basically differ in the occurrence of haploids and the ploidy level of F₁ hybrids after pollination of both types of poly-ploids with Phureja.