Mating disruption techniques

Male attraction to the female sex pheromone has been studied for the development of environmentally safe control methods. One important drawback of the mating disruption technique is that only male behaviour is affected, so the efficacy of pheromonal methods can be greatly enhanced by compounds that affect also female behaviour [378]. 

Integrating mating disruption techniques with microbial or chemical pesticides may prove efficacious. Epidemics could be suppressed with the pesticide, with the disruption technique being aimed at preventing reproduction in peripheral areas, keeping the population at low levels. The male annihilation concept, although yet to be proven in the field, offers another approach to population control. 

Many challenges remain for improvement and better understanding of the mating disruption technique for insect control. Here we discuss several points which should rank high on any list of further research needs for development of the technique. 

The most effective application technique for lepidopteran species is to permeate the atmosphere with synthetic pheromone, and to thereby prevent olfactory communication and mate finding. The mating disruption technique has been successfully applied in Europe to three lepidopteran insects from horticultural crops codling moth Cydia pomonella, and the grape berry moths Eupoecilia ambiguella and Lobesia botrana [132, 133]. 

The chemical and behavioral aspects of the sex pheromones of several forest defoliating insects of economic importance in eastern Canada are presented, with emphasis on the spruce budworm, Choristoneura fumiferana. Studies conducted over several years in New Brunswick on the use of pheromones as potential control agents, using in particular the air permeation technique to effect mating disruption, are discussed. The identification and the behavioral effects of minor components of the spruce budworm pheromone system are presented and the potential exploitation of their behavioral roles in the mating sequence in terms of control strategies are addressed. 

The racemic form is as effective as the (+) enantiomer for disrupting mating. This technique for population suppression has been evaluated in experiments to compare the effects of formulation, dose rate and population density on its efficacy. In light infestations, gypsy moth mating is effectively suppressed. Microcapsules, laminated polymeric "flakes" and hollow fibers were compared as controlled-release formulations. 

Mating disruption is the technique by which pheromone is dispensed into a pest habitat in sufficient amounts to reduce the ability of males to find females, or vice versa. Here the searching sex is attracted toward extra-high release-rate synthetic... 

Mating disruption method This pest management technique interferes directly with the communication system between the male and female, and has demonstrated successes for more than 25 years. By means of exposure to an extensive cloud of pheromone, the male insects are confused. They can no longer locate their mate, which reduces the population of the next... 

As in most Lepidoptera, spruce budworm males locate conspecific females by flying upwind along a pheromone plume. The blends and release rates of these pheromone components form an important part of a specific communication system for the species. Once the communication system of an insect is understood, especially the pheromone chemistry as it relates to male behavior, it can be used in a variety of ways. For example, pheromones can be used to detect the presence of an insect in an area, to remove males from a population by trapping or poisoning and in air-permeation techniques in which the controlled and continuous release of pheromone components in the forest can disrupt mating. The latter use of pheromones appears to alter the normal male behavioral responses to the natural pheromone (16). 

In Table III, mating communication disruption has been used as an indicator of the success of pheromone treatment. Male moth catch in (+)-disparlure-baited traps has been normalized against the number of larvae trapped pre-season, thus introducing a measure of relative population into the calculation of comparative effectiveness. The results obtained in 1980 in Maryland illustrate not only the variation of response with dose, but also the dependence of the efficacy of the technique on population levels. 

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