Effects of sublethal dose exposure to Dieldrin on Rhodnius prolixus (Hemiptera: Reduviidae) under laboratory condition

ARENDS, A. AND J. E. RABINOVICH

ACTA TROPICA

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 1980 p. 5 - 15

0001-706X

The effects of a sublethal dose of Dieldrin (7.2 x 10-5 g/day) were evaluated on oxygen consumption, survivorship. moulting and reproduction of Rhodnius prolixus. No difference was found in oxygen consumption between treated and control male insects. Survivorship proved to be very much affected by the sublethal exposure, but this was strongly dependent on the feeding stage of the individuals. Moulting times were prolonged by 2 to 3 days depending on the instar, but the number of individuals that succeeded in moulting was not affected. Total number of eggs laid by an average female was not affected, but the treated females layed fewer eggs in the first three weeks after feeding, and more eggs in the following weeks, than the untreated females. Possible physiological mechanisms that explain our results are related to the proteolytic activity of the midgut, to an interference with the hormonal system, to an insecticide hormoligasis effect, and to an interference with the ovarian follicles development. In terms of vector control these effects provide an alternative way of repopulating a sprayed house. Key words: Rhodnius prolixus; Dieldrin; sublethal dose; Hemiptera; Reduviidae; Chagas' disease; vector biology; respirometry.