Persian Journal of Acarology

Abstract The transmaternal properties of diflovidazin were examined under laboratory conditions on Tetranychus urticae. To assess its transmaternal ovicidal effect, leaf discs were dipped in a 100 ppm diflovidazin solution, after which adult females were allowed to feed on the treated surfaces for either 2 or 48 hours. The females then laid eggs on an untreated surface over five consecutive 7-hour periods. Egg mortality was evaluated based on exposure duration and time elapsed since exposure. After being removed from the treated surface, 100% of the eggs laid by females in the first 7-hour period were non-viable. However, mortality—and thus the effect—gradually decreased in subsequent periods, with eggs laid after 28 hours exhibiting mortality levels comparable to naturally occurring rates. Notably, the length of the exposure period did not influence the rate at which egg mortality declined. The effect on egg production was also examined. Females were allowed to lay eggs on treated leaf discs, but the treatment did not significantly alter the number of eggs produced per female. These findings indicate that while diflovidazin effectively induces high egg mortality, it does not reduce overall egg production. Our results suggest that diflovidazin temporarily sterilizes females, likely because developing eggs absorb the active substance from the female's system.