[Effects of 3 insecticide formulations in the removal and hatching of oothecae of Blatella germanica (Dictyoptera: Blattellidae)].

Different insecticide formulations used for the control of German Cockroach, Blatella germanica (L.) were studied to know their effects on the gravid females of this species. The insecticides assayed were baygon 20% EC, diazinon 60 EC, and licon 2.5% EC. Exposure to each insecticide showed an effect on the oothecal drop (p < 0.001). Gravid females treated with baygon had the highest percent of oothecae detached (71%); whereas diazinon caused the lowest percent (33.5%). Doses of baygon, diazinon, and icon used showed that among the oothecas detached hatching occurred only in 19.01%; 34.2% and 39.11%, respectively. Of the oothecas retained by treated females, the lowest hatching percent was produced by baygon (13.79%) compared with diazinon and icon insecticides, which presented the highest hatching percentages with 39.84 and 47.82, respectively. Therefore, the effects of insecticides on females bearing oothecas may be considered at the time of selecting an insecticide to control the German cockroach.