DoomsdaysCWHybrid #megapests evolving in #Brazil are a threat to #crops worldwide
Two extremely damaging crop pests have interbred to create hybrids resistant to more than one #pesticide that could cause serious problems in many countries
By Michael Le Page
23 January 2026
"It was thought that H. armigera and H. zea couldn’t interbreed, but in 2018 genetic analysis revealed a few hybrids between the species. Jiggins and his colleagues have now analysed the genome of nearly 1000 moths collected in Brazil over the past decade.
"They found that a third of H. armigera now carry genes providing resistance to the Bt toxin – and they got these genes from H. zea. Bt maize was first introduced in North America in the 1990s, where some H. zea strains evolved resistance. These resistance genes seem to have spread to South America and now crossed species. As yet, the hybrid H. armigera haven’t been a major problem, says Jiggins, but that could change as resistance spreads.
"The transfer has gone both ways – nearly all H. zea in Brazil now have a gene conferring resistance to a class of insecticides called pyrethroids that was acquired from H. armigera. 'We’re just sort of blown away by how rapidly it’s happened,' says Jiggins.
" 'With global connectivity and climate change together lowering barriers to species’ range expansions, such megapests are likely to be an increasing global problem, as is the escalating rate of biological invasions more generally,' says Angela McGaughran at the University of Waikato in New Zealand."
Archived version:
https://archive.ph/cgped
#Soybeans #PesticideResistance #SoybeanCrops #CottonBollworm #CornEarworm #HybridInsects #GMOs #InvasiveSpecies
Matt Osmond
Dr. Traci Birge, 🌻agroecology