Laboratory evaluation of citronella, picaridin, and deet repellents against Psorophora ciliata and Psorophora howardii.

Commercial formulations of 3 repellents: OFF Active (active ingredient [AI] 15% N,N-diethyl-meta-toluamide [deet]), OFF Family Care (AI 5% picaridin), and CVS Pharmacy Fresh Insect Repellent (AI 10% citronella, 2% lauryl sulfate, and 0.2% potassium sorbate) were evaluated to determine the mean protection time provided against the large floodwater mosquitoes, Psorophora ciliata and Ps. howardii. Each of these products contained different active ingredients and displayed different protection times, but repellency was in accordance with each product's label reapplication times/repellency durations. The CVS Pharmacy Fresh Insect Repellent provided the least protection (2 h and 26 min), followed by OFF Family Care (3 h and 46 min). OFF Active afforded the longest protection (5 h and 41 min), which was significantly higher than the other treatments (P < 0.001).

Body size, blood feeding activity, and fecundity of Psorophora howardii, Psorophora ciliata, and Psorophora ferox (Diptera: Culicidae).

Field-collected female Psorophora howardii (Coquillett), Psorophora ciliate (F.), and Psorophora ferox (Humboltd) mosquitoes were tested in laboratory conditions to measure body size, blood engorgement duration, bloodmeal size, fecundity, and egg morphology. Mean bloodmeal size was significantly different among the three species of mosquitoes, whereas there was no difference in blood engorgement duration. Mean body weights and wing lengths of Ps. howardii and Ps. ciliata were significantly greater than Ps.ferox. Seven days after bloodmeals, oviposition rates for Ps. howardii, Ps. ciliata, and Ps.ferox were 18.8, 56.2, and 0%, respectively. The mean number of total eggs produced per female for the three species was 59, 81, and 73, respectively. Mean egg lengths of Ps. howardii and Ps. ciliata were significantly greater than Ps.ferox, and egg diameters for each of the three species were significantly different from one another. Length per diameter ratios of Ps. howardii and Ps. ciliata were significantly smaller than Ps. ferox. Bloodmeal size was positively related to body weight, but not related to blood engorgement duration, and the total egg number was positively related to bloodmeal size.