Dysdercus ruficollis (Linnaeus, 1764), usually known as "cotton stainers", were treated at the beginning of the fifth intar nymphs, with a juvenile hormone analogue (N(5-chloro-2-methylphenil)-3,7-dimethyl-2,6-octadienylamine), applied topically to the base of wings. After ecdysis the insects showed a dried up appearance, external morphological alterations on the head, thorax, legs, wings and abdomen, hindering their normal activities. However, the external genitalia of both sexes were inaltered. The use of this substance was able to interrupt the biological cycle of the insects.