Laboratory evaluation of BAY SIR 8514 against the house fly (Diptera: Muscidae): effects on immature stages and adult sterility.

Abstract

Medium containing eggs or 1st, 2nd, or 3rd instars of Musca domestica L. was treated with BAY SIR 8514 (2-chloro-N-[[[4-(trifluoromethoxy)phenyl]amino]carbonyl]benzamide), and its effects were evaluated on the basis of percent forming puparia, percent deformity, percent eclosion, and larval length at 48 and 72 h of development. Rates (g of AI/0.09m2) evaluated ranged from 0.0263 to 0.0066 g for 25 WP and 0.0263 to 0.0016 g for 0.5 EC. Mortality, as reflected by percentage of larvae forming puparia, was greatest in treatments of the egg and 1st instars for both WP and EC formulations; treated 2nd instars were less affected, with 36 to 66% of larvae forming puparia. The number of puparia from treated 3rd instars and untreated larvae was about equal. Deformed puparia were elongated, shortened, or “C” shaped; amount of deformity was greatest following treated eggs or 1st instars and decreased with maturity of stage treated. Eclosion was greatly inhibited by all treatments; only random and isolated occurences of eclosion were observed except at the lowest rate of EC and never exceeded 13%. No adults from treated medium survived beyond 5 days posteclosion, and none produced eggs for rearing. Larval growth (as determined by length of larvae) was significantly retarded in all treated stages except the 3rd instar. No ovicidal activity was exhibited by BAY SIR 8514 to eggs topically treated at 2,500 ppm; treatments of pupa ria at the same rate had no significant effect on adult emergence or fertility. There was a significant degree ( P = 0.05) of sterility induced in adult flies for up to 21 days (only 27.1% hatch) after exposure to a granulated sugar and WP bait at concentrations as low as 0.0156%. Sterility induced by contact with treated paper (0.5 EC) was not as permanent as exposure to bait, except at the highest rate of 0.0376 g of AI/0.09m2, and then results were comparable only to 14 days post treatment.