Field Responses of Tsetse Flies (Glossinidae) and Other Diptera to Oils in Formulations of Deltamethrin

Abstract

Investigations were conducted to establish field responses of Glossina pallidipes, G. m. morsitans, muscoids and tabanids to castor, raw linseed, paraffin and chlorinated paraffin oils in deltamethrin suspension concentrate (sc) formulation, through randomised Latin square experiments. Tsetse landing responses on targets treated with 400 ml/m 2 of any of the oils in 2 g/ m 2 deltamethrin formulation were significantly lower than on non-oil-containing deltamethrin formulations, for both G. pallidipes (F (4 , 32) = 4.855, P = 0.00357) and G. m. morsitans (F (4/32 )=2.421, P = 0.06862).The landing response indices, relative to the control formulation without oil, were 0.60, 0.70, 0.61 and 0.41 in G. pallidipes and 0.92,0.82,0.75 and 0.42 in G. m. morsitans and for paraffin, chlorinated paraffin, castor and raw linseed oils respectively. Glossina pallidipes and G. m. morsitans landing responses were inversely proportional to raw linseed oil concentrations. None of the oils significantly affected muscoid (F (4/32) = 1.6959, P = 0.1753) or tabanid (F (4<32) = 1.7546, P = 0.1624) landing response, or tsetse fly resting persistence (F( 4 32 ) = 0.9641, P = 0.4406) on the targets.The reduced tsetse fly response to targets treated with any of the oils can be attributed to adverse effect of the oil treatments on the tsetse fly olfactory responses to the targets. Since the oil formulations reduce target efficiency by reducing tsetse responses to the targets, application of the oil formulations on targets deployed in G. pallidipes and G. m. morsitans control programmes is not recommended. 317 318 P. O. MIREJI et al. 1.7546, P = 0.1624), ou le temps de repos des mouches tse-tse (F (432 )= 0.9641, P = 0.4406) sur les pieges.La diminution de la reponse des mouches tse-tse sur les pieges traites avec n'importe quelle huile peut etre attribute a un effet negatif de l'huile sur la reponse olfactive des mouches tse-tse sur les pieges. Puisque les formulations a base d'huile reduisent l'efficacite des pieges en reduisant la reponse des mouches tse-tse aux pieges, I'application de formulations a base d'huile sur les pieges utilises dans les programmes de lutte contre G. pallidipes et G. m. morsitans est deconseillee.

Genome-Wide Comparative Analysis of Chemosensory Gene Families in Five Tsetse Fly Species

“…Efforts to suppress tsetse populations include trapping, which rely on traps baited with various host derived odours [ 8 – 10 ]. Differences in response to the available baits have been observed among tsetse species and/or between males and female flies [ 11 , 12 ]. For example the palpalis/riverine species are thought to be attracted to kairomones released by monitor lizards, but unresponsive to odours that are highly attractive to Savannah species [ 13 ].…”

Responses of Glossina pallidipes and Glossina morsitans morsitans tsetse flies to analogues of δ-octalactone and selected blends

“…The effects of δ-octalactone and δ-nonalactone with/without 4-methylguaiacol on G. pallidipes catches in NG2G traps baited with acetone (~500mg/h) and fermented cow urine (1000mg/h) (Brightwell et al, 1991) were evaluated in the field in randomized Latin squares design (5 targets × 5 sites × 5 days) arrangement (Mireji et al, 2003; Bett et al, 2015). The traps were deployed in clearings about 300m apart.…”

Odorant and Gustatory Receptors in the Tsetse Fly Glossina morsitans morsitans

“…The repellents include guaiacol (methylphenols), δ-octalactone and methylketones [16] – [18] and 2-methoxy-4-methylphenol [14] . Natural differential responses among tsetse species and even between sexes and allopatric populations of the same species have been observed [18] – [22] , which have stimulated research and design to enhance the efficiencies of the existing attractant-based bait technologies, to develop new ones based on repellent blends (‘push’ tactics) from refractory animals, and to integrate these into ‘push-pull’ strategies. Different Glossina species exhibit different olfactory uniqueness' and this may partly account for the observed graduation of preferences for particular hosts.…”