Mosquito adults

Although CHC profiles tend to be species-specific (reviewed by Howard, 1993 and by Howard and Blomquist, 2005), in many species they cannot always be reliably used as phylogenetic markers - this is particularly the case in many drosophilids (Ferveur, 2005 see also Chapter 7). Examples of qualitative geographic variability in Drosophila CHCs have been given above. In Anopheles mosquitoes, adult CHCs can be used to reliably discriminate between populations in both inter- and intra-specific studies (Phillips et al., 1990 Anyanwu et al., 1993). However, this variability suggests they may not always be reliable for identifying species. 

Botanical insect repellent products, MosquitoSafe (25% geraniol oil) and SunSwart, were the most effective in causing mortality of mosquito adults. Most botanical insect repellent products tested by Xue et al. showed a different mortality of adult mosquitoes at 24 hours posttreatment. The species of mosquitoes used and the insect repellent products tested in the laboratory resulted in different mortality of Aedes, Culex, and Anopheles mosquitoes. ... 

Table III. It is obvious from the data in Table III that the housefly and the mosquito, in both the adult and larval stage, are susceptible to insecticides of the DDT type. However, the extravagant claims that DFDT is far superior to DDT as a contact insecticide against flies are not borne out by the results of controlled laboratory tests. The Peet-Grady testing technique used by Prill (92) would indicate that in the presence of added pyrethrins DDT is definitely superior to DFDT when applied as a spray. On the other hand, DFDT gave higher percentage kills than DDT when flies were placed under a Petri dish and held in contact with deposits of the compounds on glass surfaces. A comparison of the activity of these compounds against adult mosquitoes has not been reported.

It is normally found in Africa, Asia, and Australia. The natural reservoirs are mosquitoes and midges. Insects remain infected for life. It causes abortions, stillbirths, premature births, and various dysfunctions or deformities in newborns. Adult animals are not clinically affected by the virus. 

The presence of sediments in diflubenzuron marine microcosms results in rapid removal from seawater and ultimately a reduction in mortality of larval crustaceans (Table 17.2) (Cunningham et al. 1987). But marine sediments that exceed 200 pg diflubenzuron/kg — levels normally encountered at application rates for control of salt marsh mosquitoes — could be detrimental to juvenile and adult crustaceans that consume detritus and organic matter on the surface of the marsh or at the water-sediment interface (Cunningham and Myers 1986 Cunningham et al. 1987). 

The preparation of test mosquito coils complied with the method described by Yamaguchi et al. The test coil was fitted on a coil holder and placed at the center of the chamber (4.3 m x 2.65 m x 2.45 m). The coil was ignited and then 100 adult female mosquitoes were released into the chamber. The number of knocked down mosquitoes was counted at the designated intervals for 75 min. 

On the other hand, the lethal efficacy for adult house flies (Musca domestica) is about the same as D-allethrin and approximately 0.5 that of prallethrin. In addition, the efficacy for female adult German cockroaches (Blattella germanica) is approximately twice that of D-allethrin and approximately 0.5 that of prallethrin. From the results mentioned above, we can see that Metofluthrin has an extremely high lethal efficacy for mosquitoes in particular. 

Zhu J, Zeng XY, Liu T, Qian K, Han Y, Xue S, Tucker B, Schultz G, Coats J, Rotvley W, Zhang A, Adult repellency and larvicidal activity of five plant essential oils against moscgmocs, J Amer Mosquito Control Assoc 22-3 b— b22, 2006. 

Out of Doors. Control measures against adult mosquitoes out of doors have been discussed by Ginsburg ( 1), Coveil et al. (P), Russell and Knipe (45), and others. These workers used pyrethrum in oil sprays and were instrumental in reducing malaria or mosquito annoyance. 

Applications from the Ground. Early in the war the Orlando, Fla., laboratory of the Bureau of Entomology and Plant Quarantine demonstrated the effectiveness of DDT sprays and aerosols as a means of controlling adult mosquitoes under outdoor conditions (55, 55, 36). 

In Alaska, Wilson and others (57) have tested ground aerosol generators for controlling adult mosquitoes. In one test they used 25 gallons of Navy fog oil, 15 gallons of fuel oil, 8 gallons of Velsicol AR-60 (chiefly di- and trimethylnaphthalenes), and 25 pounds of DDT and in another test 5% of DDT in fuel oil. Satisfactory controls were obtained for only a few hours. 

Dicldnson and associates (1 ) reported that the Consolidated Mosquito Abatement District of Fresno County, Calif., stopped a large population of Aedea mosquitoes from biting as soon as the clouds produced by an insecticide fog applicator had passed the field. This machine was also used to treat 160 acres of irrigated pasture land that had been considered untreatable. After 24 hours no adult mosquitoes were observed. 

Thermal-aerosol applicators are employed to a considerable extent in the outdoor application of adulticides (sprays designed for killing adult mosquitoes). Well over 2,(XX),000 gallons of oil are used annually in these applicators. 

Applications from the Air. Solutions of DDT in fuel oil or other solvent applied from airplanes as fine sprays have been found to destroy a large percentage of adult mosquitoes even in dense tropical jungles. 

Davidson (10) reported on the use of petroleum oil containing benzene hexachloride as a means of malaria control by adult mosquito destruction in western Africa. He concluded that an oil solution containing 0.5% of the gamma isomer of benzene hexachloride (Gammexane) sprayed on the inside wall surfaces of all houses at the rate of 10 mg. of gamma per square foot (2 quarts of solution to 1000 square feet) practically eliminated mosquitoes in those houses for about 6 months. 

Additional research to find a suitable carrying agent having low explosive and flammability properties is urgently needed as we increase the control of adult mosquitoes by fogs and sprays dispersed by the new types of applicators. 

For control of flying insects with aerosols, research showed that there is an optimum particle size needed to obtain maximum kill. The size was determined through extensive research in wind tunnels (2) and Peet-Grady chambers in which the most nearly homogeneous sprays possible were used. For adult mosquitoes the optimum particle size was found to be between 10 and 15 microns mass median diameter and for adult houseflies between 15 and 20 microns. 

Vizioli, J., Richman, A.M., Uttenweiler-Joseph, S., Blass, C., and Bulet, P. (2001) The defensin of the malaria vector mosquito Anopheles gambiae antimicrobial activities and expression in adult mosquitoes. Insect Biochem. Mol. Biol. 31, 241-248. 

Hadaway, A.B., Barlow, F., Turner, C.R. (1970) The effect of particle size on the contact toxicity of insecticides to adult mosquitoes. Bull. Entomol. Res. 60, 17. 

Uses Pure fenthion is a colorless liquid. Technical fenthion is a yellow or brown oily liquid with a weak garlic odor. It is grouped by the USEPA under RUP and requires handling by qualified, certified, and trained workers. Fenthion is used for the control of sucking and biting pests (e.g., fruitflies, stem borers, mosquitoes, cereal bugs). In mosquitoes, it is toxic to both the adult and the immature forms (larvae). The formulations of fenthion include dust, emulsifiable concentrate, granular, liquid concentrate, spray concentrate, ultra-low volume, and wettable powder.28... 

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