Embryogenèse et Relations Nucleocytoplasmiques chez les Hybrides experimentaux entre Bufo bufo l., Bufo viridis LAUR. et Bufo calamita LAUR

AbstractHybridization between three european species of Bufonids (B. bufo; B. viridis and B. calamita) has been performed under laboratory conditions. Developmental analysis have shown that morphogenesis is very often affected by hypomorphosis. When hybrids are viable up to an advanced stage, it is possible to disclose expression ofparental characters. Developmental difference between reciprocal crossings compared to nucelocytoplasmic hybridization (interspecific nuclear graft) lead to show a viability which is always greater for hybrids formed with B. bufo eggs. This remark joined to injection experiments ofcytoplasmic fractions (DELARUE, 1981)emphasizes qualitative differences of each species receiving egg cytoplasm about their morphogenetic potentialities.