Safety of genetically modified glyphosate-tolerant eucalyptus designed for integrated weed management

Abstract

Background: Eucalyptus is the primary cultivated wood species in Brazil, covering 7.5 million hectares. Weed competition in eucalyptus plantations reduces yield and increases operational costs. FuturaGene/ Suzano has developed genetically modified (GM) eucalyptus varieties with glyphosate herbicide tolerance (HT) as a modern tool for improving weed management practices in plantations. The first event received regulatory approval for commercial deployment in 2021. However, the introgression of a new GM trait into eucalyptus, a non-isogenic species, cannot be achieved through selfing or backcrossing. To overcome this limitation and expedite the introgression of HT into the breeding population, multiple GM events were generated, in various genetic backgrounds and genomic locations, enabling simultaneous crossing with numerous elite parents. Objective: To characterize the newly developed HT GM eucalyptus events and assess their safety for the environment and wood production. Methods: HT GM eucalyptus events were subjected to genome sequencing and glyphosate tolerance testing. Biosafety analyses and environmental impact assessments were conducted through field trials in various eucalyptus cultivation regions, comparing the HT GM eucalyptus with conventional clones. Results: The new events proved highly tolerant to glyphosate and displayed different genomic insertion sites. No adverse effects on non-target organisms were observed, and there were no significant differences in the soil microbiota or decomposition profile. Conclusions: The HT GM events have been proven to be safe, posing a low risk to the environment, humans, and animals. Consequently, these HT GM eucalyptus varieties can be confidently utilized for wood production. Avisar D, Dias TB, Santos AA, Galan MP, Gonsalves JMW, Graça RN, Livne S, Manoeli A, Menezes TRD, Porto ACM, Rocha CS, Pinheiro A.