Two trispecific synthetic allotetraploids have been obtained using the Australian diploid species G. sturtianum, the main cultivated amphidiploid, G. hirsutum, and two American wild diploid species : G. thurberi and G. raimondii. Observation in the progeny of these trispecific hybrids revealed the expression of the gossypol glands morphogenesis repressive mechanism of G. sturtianum in a rather high proportion of the BC1 seeds (6 on 41). In these materials, the glandless-seed and glanded-plant trait seems to be linked to a lethal factor. Only one of the six totally glandless BC1 seeds gave an adult plant. In vitro culture of the seed and grafting of the plantlet at a early stage on G. hirsutum were necessary to obtain a normal development of this genotype. All the other glandless materials died just after germination or never germinated. The survival plant will be used in a backcrossing programme to obtain the introgression of the glanded-plant and glandless-seed character into G. hirsutum.