With mealybugs contributing to notable virus spread – particularly grapevine leafroll viruses – in some Australian vineyards, we share some pilot research being undertaken by Washington State University, attempting to use pheromones to disrupt mealybug mating to reduce damage in vineyards.
The mealybug crawler stage is predominantly attributed to spreading grapevine viruses. After hatching, crawlers feed on one vine and move to the next, either by walking or through wind dispersal, and this can spread virus between vines.
A PhD study being undertaken at Washington State University is assessing the efficacy of mating disruption using pheromone-coated twist ties attached to grapevines, to reduce crawler populations.
The premise is that these ties are placed in a confined area and emit synthetic female sex pheromones, confusing male mealybugs who won’t then be able to communicate with females. This will in turn prevent mating, reducing the next generation of crawlers. Results from initial studies are expected in Australian spring 2021.
Read the full article ‘Disrupting mealybug mating may help protect vineyards’ run by the Western Farmer-Stockman on 22 June 2021.
Background
Insect pheromones are viewed as positive forms of pest control as they are species-specific, active in very small concentrations and the vast majority are non-toxic to animals, humans, beneficials and the environment.
In European vineyards, pheromone-mediated mating disruption was reported to have been implemented on approximately 140,000 hectares 10 years ago. Where it was successfully applied as an areawide strategy, reduction in insecticide use was reported to have improved the quality of life for growers, consumers, as well as the public living near wine-growing areas, reducing the conflict between agricultural and urban communities (Ioriatti et al., 2011).
Increased food security for a growing population in a changing climate with higher growing season temperatures and altered rainfall patterns has also been reported as a positive from the use of mating disruption, unlike intensified insecticide use, to control native and invasive insects by Witzgall et al. (2010).
References
Ioriatti, C., Anfora, G., Tasin, M., De Cristofaro, A., Witzgall, P. and Lucchi, A. (2011). Chemical Ecology and Management of Lobesia botrana (Lepidoptera: Tortricidae), J Econ Entomol, 104 (4), 1125–1137. https://doi.org/10.1603/EC10443.
Witzgall, P., Kirsch, P. and Cork, A. (2010). Sex Pheromones and Their Impact on Pest Management. J Chem Ecol 36, 80–100. https://doi.org/10.1007/s10886-009-9737-y.