Differential response to irradiation in offspring of freshwater and seawater substrains of Poecilia (Lebistes) reticulata peters in the "guppy male courtship activity test".

An inbred strain ("Istanbul") of guppies was divided into two substrains, one of which was maintained and bred in seawater. The offspring of irradiated animals of both substrains (1000 R X-rays to spermatogonia and oogonia of neonatal fish) were tested in a new "gruppy male courtship activity test" and compared with control groups. The postirradiation response in the seawater substrain was more intense than in the freshwater substrain.