Zur Entwicklung und Lebensstrategie von Dysdercus albofasciatus

STADLER, T.; CAPPOZZO, H.L

Deutsche Gesellsch. algem. angew. Entomol.

Mitt. dtsch. Ges. Allg. Angew

Año: 1988 vol. 6 p. 338 - 342

On the development and adaptative strategies of the ?cotton stainer?, Dysdercurs albofasciatus (Berg, 1878) (Hemiptera:Pyrrhocoridae). D. albofasciatus is endemic in Argentina, Paraguay, Uruguay and Brazil, and its distribution correlates with the ?cotton ecological region? (Papadakis, 1975). It is possible to define a habitat-binding of this species with areas containing the basic floristic structure of the ?Barranca Paranaense? (Pawrodi, 1940). The activity of the population that survives through the winter, starts in August with average temperatures of 12.5ºC and mean values of rainfall of 70mm, in connection with available kleistogram flowers of the host, Pavonia malvacea (Vell.) Krap. et. Crist. The life cycle of D. albofasciatus, from egg to imago, needs 25 to 61 days. The whole annual cycle involves four to five generations (34º00?S) and this fact is mightily affected by environmental and nutritional factors. Differences in population densities become influenced directly through rainfall. Thus in dry periods the mortality of embryos and early instars increases and, on the other hand, the population?s density outbreaks in wet periods. ?Life cycle flexibility? allows D. albofasciatus to adopt alternative strategies during its development. Environmental influences variations affecting reproduction, migration or development