The silver whitefly is the main pest of agricultural crops in the tropics and subtropics, as well as in protected ground everywhere. After studying its genome, the researchers identified 49 plant genes transferred into the insect's own genome. Phys.org portal.
Such a large number of genes passed between plants and insects have never been found before. This data can help develop innovative pest management practices and reduce the use of pesticides.
The war between plants and herbivorous insects goes back millions of years. As plants transmit signals and erect physical and chemical barriers, insects develop ingenious strategies to bypass these barriers. The genes involved in insect adaptations sometimes have surprising origins.
Recent studies in 2020 and 2021 have shown the transfer of two plant genes into the silver whitefly (Bemisia tabaci) genome, with one gene giving the whitefly the ability to neutralize plant-produced toxins as a defense mechanism. Intrigued by the discovery, scientists at the National Research Institute for Agriculture, Food and the Environment tried to find out how many plant-derived genes were found in the whitefly genome, which was fully sequenced in 2016. Their current research is published in the journal Genome Biology and Evolution
Through bioinformatics analysis, the researchers identified 49 plant genes in genome whiteflies derived from 24 independent horizontal gene transfer events. Most of these genes show features of functionality, which means that they are expressed in insects and have evolutionary pressure sequences and therefore have a potential role in insects.
The researchers' results also show that most of the identified genes, such as those involved in the production of enzymes that break down plant cell walls, play a role in the relationship between plants and their parasites. This probably reflects the result of a natural selection process. plant genes in insects, which may have allowed the whitefly to adapt to a wide range of plant species. The origin and mechanism of these transfers are still unknown, but they all date back several million years.
This is the first time that so many gene transfers between plants and insects have been identified. This research opens the door to new research into plant-pest relationships and crop pest management practices. Understanding the role of the transferred genes for plants and insects can lead to the development of innovative pest control methods based on varietal breeding that can reduce the use of pesticides.