October 2024
This article is the second in a series providing case studies of biocontrol products that are on the market or under development in Europe.
Biocontrol uses substances, technologies or mechanisms derived from nature to control insect pests, diseases and weeds in agriculture and forestry. Biocontrol products generally fall into the following categories, depending on the “active ingredient” of each:
The European grapevine moth (Lobesia botrana) is a major pest of grapes, berries and similar fruits throughout much of the world. Its larvae feed on the flowers or fruit of host plants, most often grapes, increasing their susceptibility to fungal infections. This makes the moth one of the most economically damaging pests in wine and table grape-exporting countries. In Europe, the pest principally affects France, Spain, Portugal, Greece, Italy and Mediterranean islands.
Traditionally treated with conventional synthetic pesticides, the moth can now be controlled with a semiochemical, several microbials and many macrobial natural enemies, according to a 2021 study. For example, the use of a female pheromone helps control moth populations via mating disruption. It interferes with the moth’s olfactory chemical communication, which disorients males and keeps them from finding females. The pheromone is targeted and “ecologically clean” with no residues, however, it is not very effective against high levels of infestation.
In the latter case, there are microbial solutions such as biopesticides based on Bacillus thuringiensis (Bt) bacteria – the most widely used biocontrol products worldwide due to their toxicity to a wide range of insect pests but harmlessness to humans. Bt microbials – particularly sub-species Bt kurstaki and aizawai – are effective against European grapevine moth larvae.
In addition, around 21 insect species are predators of the moth and 97 other insect species can parasitise it. Campoplex capitator, a type of fly, is one of the most effective parasites due to its natural efficiency, density and wide geographic distribution. It has been regularly found in most European vineyards. Mass-releasing these insects at the start of the season can reduce later generations of the moth. Also effective are Trichogramma insect species, which attack moth eggs, controlling the pest before it can cause harm.