New insect research shows that caterpillars (Spodoptera litura) can eat anything thanks to the expansion of genes involved in taste and detoxification

An international team, including Prof. Guy Smagghe (Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University), has discovered using modern molecular techniques, that the Spodoptera litura caterpillars have developed a huge arsenal of gene families, which allows them to eat almost anything.

The Spodoptera litura is a butterfly that is a threat to many crops. He feeds with more than one hundred different plant species, including rice, corn, cotton, many vegetables, (sweet) potatoes, cabbage and soybeans. Crops that are crucial to food security.

Toxic insecticides digestion

This project has shown that the genome of S. litura has a size of 438.32 Mb and that remarkable expansions have occurred, for example of taste receptors and detoxification enzymes. These adjustments allow the caterpillars to eat and detoxify, for example, bitter or toxic substances.

This ability, along with an enormous rapid spreading mobility throughout Southeast Asia, made it possible for these caterpillars to adapt to different ecosystems. This way they can even eat more different plant species and even digest the most toxic insecticides.

Genetic resilience

These caterpillars are among the most widespread and destructive pests in agriculture. They can destroy complete crops. Research on harmful insects in agriculture is therefore extremely important.

"With caterpillars like Spodoptera as a research model, we have already made several important contributions to unraveling the growth process and the development of insects. The new insights of this study demonstrate their enormous genetic resilience," explains Professor Smagghe. "The results should help us to control harmful insects in an efficient and environment friendly way. This type of caterpillars now causes very significant damage to Southeast Asia, but it can spread rapidly, also towards Europe. Food security and agriculture are at risk."