Biological control of ticks

Abstract

Ticks have numerous natural enemies, but only a few species have been evaluated as tick biocontrol agents (BCAs). Some laboratory results suggest that several bacteria are pathogenic to ticks, but their mode of action and their potential value as biocontrol agents remain to be determined. The most promising entomopathogenic fungi appear to be Metarhizium anisopliae and Beauveria bassiana, strains of which are already commercially available for the control of some pests. Development of effective formulations is critical for tick management. Entomopathogenic nematodes that are pathogenic to ticks can potentially control ticks, but improved formulations and selection of novel nematode strains are needed. Parasitoid wasps of the genus Ixodiphagus do not typically control ticks under natural conditions, but inundative releases show potential value. Most predators of ticks are generalists, with a limited potential for tick management (one possible exception is oxpeckers in Africa). Biological control is likely to play a substantial role in future IPM programmes for ticks because of the diversity of taxa that show high potential as tick BCAs. Considerable research is required to select appropriate strains, develop them as BCAs, establish their effectiveness, and devise production strategies to bring them to practical use.

Microorganisms contaminating ticks collected at natural reserves or wild animals

“…Biological control of tick vectors is an alternative to currently used acaricides that pollute and their efficacy is decreasing with the selection of resistant parasite populations (SAMISH et al, 2004). Actually, several fungi such as Metarhizium anisopliae and Beauveria bassiana are pathogenic to ticks.…”

Studies on the application of the sterile-male technique on the tick Hyalomma excavatum

“…The increasing resistance of ticks to pesticides is another adverse effect (5,18). A well established, successfull approach to this problem should be the use of biological agents or methods (11,17).…”

DeterminaÇão da CL90 e TL90 do isolado IBCB66 de Beauveria bassiana (Ascomycetes: Clavicipitaceae) para o controle de Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

“…Presentemente, a maioria das pesquisas produzidas, com o objetivo de empregar agentes microbianos no controle de carrapatos, concentra-se na utilização de fungos entomopatogênicos (SAMISH et al, 2004) Os fungos apresentam vários fatores altamente vantajosos que os tornam uma excelente opção para o controle de ectoparasitas. São patógenos de largo espectro, capazes de atacar insetos e ácaros, promovendo epizootias naturais; infectam diferentes estágios de desenvolvimento dos hospedeiros, como ovos, larvas, pupas, ninfas e adultos, característica desejável e particularmente observada nos diferentes grupos de artropodos.…”

“…Nesse grupo de micro-organismos, as espécies Metarhizium anisopliae e Beauveria bassiana são apontadas pela literatura como as mais promissoras para utilização como agentes microbianos (SAMISH, et al, 2004).…”