PROTEIN HYDROLYSATES AND ASSOCIATED BACTERIAL CONTAMINANTS AS OVIPOSITION ATTRACTANTS FOR THE MOSQUITO CULEX-QUINQUEFASCIATUS

Six protein or protein hydrolysate solutions were tested for activity as attractants for ovipositing Culex quinquefasciatus mosquitoes in th e laboratory. Four of these solutions (egg albumin, lactalbumin hydrol ysate, casein hydrolysate and yeast hydrolysate) were attractive to ov ipositing females at varying concentrations, when compared to distille d water controls. Soy hydrolysate was repellent at 1%, but not signifi cantly attractive or repellent at lower concentrations. 'Nulure', a te phritid fly bait containing protein hydrolysate, also had no significa nt effect on oviposition behaviour. Gravid females mostly oviposited w ithin the first 4 h of the scotophase, regardless of the presence or a bsence of an oviposition attractant. Lactalbumin hydrolysate 1% soluti on, with or without 0.1% neomycin antibiotic, was attractive to Cx qui nquefasciatus. This effect was reduced by the presence of neomycin whi ch, alone, had no effect on oviposition. Hence both lactalbumin hydrol ysate and bacterial contaminants were shown to be attractive to gravid Cx quinquefasciatus.