Effects of certain pesticides on the embryogenesis of Boophilus annulatus (Say) . Ixodoidea. Ixodidae
el-Kammah, K.M.; Gomaa, E.A.; Oyoun, L.I.
Journal of the Egyptian Society of Parasitology 17(2): 583-589
1987
ISSN/ISBN: 1110-0583 PMID: 3693956 Document Number: 287619
The effects on embryogenesis of serial concentrations of SIR-8514 was studied in Boophilus annulatus. The concentrations used were 2-0.0005%, 4-0.0005% and 8-0.0005% a.i., respectively. Eggs were placed on impregnated filter papers and kept at 30 degrees C and 75% RH. Hatch rates increased with decreasing concentrations of acaricide. No eggs hatched at the 2, 4 and 8% concentrations, while 70, 76 and 84% hatched when exposed to 0.0005% of triflumuron, diazinon or chlorobenzilate, respectively. Observed LC50s were 0.005-0.01, 0.01-0.02 and 0.1%, respectively. At 8 days postoviposition (POP), most of the examined sections of eggs exposed to LC50 concentrations of triflumuron showed zygote nuclei division only; blastula development was observed at 11 days POP. Few eggs exposed to LC50 concentrations of diazinon reached the blastula stage, but eggs exposed to chlorobenzilate developed further, with cells accumulating around the opisthosoma at 11-15 days.