Tick pheromones

This section will review selected field tests that have been carried out to establish monitoring or control systems with behavior modifying chemicals. Actually, four orders of insects, Lepidoptera, Coleoptera, Hymenoptera, and Diptera, contain most pests for which manipulation by behavior modifying chemicals has been attempted. (A few studies of tick pheromones have been reported.) It is convenient to divide them into pests of forest and shade trees, orchard trees and vines, field crops, stored products, and those that directly afflict humans or animals. 

The previously reported 2,6-dichlorophenol, which is a sex pheromone of several species of tick (1), is also produced by the African tick Amblyomma hebraeum (1662, 1663). This pheromone has been used to control the African bont tick on... 

Lusby WR, Sonenshine DE, Yunker CE, Norval RA, Burridge MJ (1991) Comparison of Known and Suspected Pheromonal Constituents in Males of the African Ticks, Amblyomma hebraeum Koch and Amblyomma variegatum (Fabricius). Exp Appl Acarol 13 143... 

Norval RAI, Sonenshine DE, Allan SA, Burridge MJ (1996) Efficacy of Pheromone-Acaricide-Impregnated Tail-Tag Decoys for Controlling the Bont Tick, Amblyomma hebraeum (Acari Ixodidae), on Cattle in Zimbabwe. Exp Appl Acarol 20 31... 

Sonenshine DE, Taylor D, Corrigan G (1985) Studies to Evaluate the Effectiveness of Sex Pheromone-Impregnated Formulations for Control of Populations of the American Dog Tick, Dermacentor variabilis (Say) (Acari Ixodidae). Exp Appl Acarol 1 23... 

Guanine (Ar54) and xanthine (Ar55) are components of the arrestment pheromone of the tick Ixodes scapularis264... 

The Cyphophthalmi of the genera Cyphophthalmus and Siro revealed more than 20 compounds including saturated and unsaturated Cn-C15-methyl ketones, for example, tridecan-2-one (67), four naphthoquinones (especially 1,4-naphthoquinone (53), 6-methyl-1,4-naphthoquinone (52), 4-chloro-1,2-naphthoquinone (51) and its 6-methyl analogue), and acetophenone (50).133 Chlorinated exocrine compounds of arthropods seem to be particularly unusual, apart from chlorophenol, a sex pheromone of ticks.133 As a whole, Cyphophthalmi are chemically more similar to Palpatores than to Laniatores. 

Ectoparasites such as ticks, mites and haematophagous flies together with certain endoparasites may be "managed" by use of avermectins (macrocyclic lactones) or hormone analogues and by Immunization of the hosts with antigens derived from the vectors or parasites themselves. Recently this combined approach has been used most effectively against helminth infestations as well as against ticks and flies. Use of components of host odors and pheromones to trap, sterilize or kill tsetse flies is described as well as inexpensive methods of crop and livestock protection, such as oils and plant extracts, used traditionally in less developed countries. 

Organohalogens also serve as hormones. Vegetables such as lentils, beans, and peas synthesize the growth hormone 4-chloro-3-indoleacetic acid. A cockroach produces two chlorine-containing steroids as aggregation pheromones. Female ticks use 2,6-dichlorophenol as a sex attractant. Thyroid hormones (see Figure 1) contain iodine, and an organobromine is involved in the mammalian sleep phenomenon. 

Halogenated phenols are also known as bactericidal and fungicidal substances they also occur in nature. It is interesting that 2,6-dichlorophenol has effects as a sexual pheromone on the female ticks of Amblyomma amer-icanum. 

By use of myo-inositol and turanose as internal standards, mannitol and lactulose were determined in the present of glucose as their pertrimethylsilylated derivatives during an intestinal permeability test. Purine and pyrimidine nucleosides and bases, and uric acid, all parts of the assembly pheromone of ticks, were detected by g.c.-m.s. analysis of pertrimethylsilylated derivatives using an ion-trap detector. ... 

Figure 8.10 Phenols and resorcinols from metapleural glands of an ant andfrom defensive glands of millipedes and opilionids. Their function is undetermined but is probably antibiotic and defensive. 2,6-Dichlorophenol is the sexual pheromone of a number of species of ticks...

The sex attractant of several tick species have been identified, but only three examples of attempts to apply the attractant have come to our attention. Sonenshine has demonstrated (620) mating disruption by dusting a tick-infested dog with a microencapsulated formulation of the pheromone, 2,6-dichlorophenol the ticks used were the dog tick, Dermacentor variabilis, and the Rocky Mountain wood tick, Dermacentor andersoni. Gladney (621) applied a mixture of pesticide and male extract to a shaved area on the shoulders of cattle and found that the Gulf Coast tick (Amblyoma maculatwn) could be attracted to the spots and killed... 

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