Brazil’s Embrapa develops bioinsecticide against fruit flies with fungus from Amazon soil

The Brazilian Agricultural Research Corporation (Embrapa) has developed a microbiological insecticide based on the fungus, Metarhizium anisopliae, which was isolated in soil from the Amazon region of Macapá. According to researchers, the bioinsecticide targets various species of fruit flies, including the quarantined pest, Bactrocera carambolae.

Because it was obtained from the Amazon environment, scientists stressed that the microorganism is ideal for controlling fruit flies that occur in tropical environments. This technological asset has also proven effective in controlling Anastrepha fraterculus, Ceratitis capitata and Bactrocera dorsalis, which are all economically-significant pests in fruit cultivation.

According to Embrapa, the bioinsecticide is the first product formulated with the fungus, Metarhizium anisopliae, for controlling Bactrocera carambolae. It eliminates the insect through direct application in the soil. Results have shown that, under field conditions, the control percentage achieved with the technology was high, reaching up to 87%. In addition to not being toxic, it is a residue-free product that poses no risk to the environment and acts against the pest’s larvae, pupae and adults that are still in the soil.

In terms of adults originating from treated soil, a significant portion will emerge infected and will die before completing their pre-oviposition period, so they will not produce descendants. Regarding the current status of the product formulation, it is awaiting private sector partners interested in producing and commercializing it.

Embrapa offers opportunities for further studies to extend the product's shelf life and additional tests against other species of economically-significant insects. "The use of this microorganism formulation for controlling Bactrocera carambolae is a real possibility, since it demonstrates significant control effectiveness and ease of commercial-scale production," said Embrapa researcher Adilson Lopes Lima.

The phylogenetic similarities and life cycles of target pests can also promote expansion to other potential markets. "Bactrocera carambolae is a species that is part of the Bactrocera dorsalis complex, with some 85 species being genetically very close," Lima said. 

As B. dorsalis is one of the world's most destructive agricultural pests and a major limiting factor for international trade in fresh fruits, the use of this Embrapa asset has the potential for significant economic, social and environmental benefits, he added.

(Editing by Leonardo Gottems, reporter for AgroPages)