Author
Alejandro J Sosa
alejsosa@fuedei.org
Fundación para el Estudio de Especies Invasivas (FuEDEI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)
Hurlingham
Coauthors
Melissa Smith, USDA-ARS Invasive plant research, Fort Lauderdale, USA
Julie A Coetzee, CBC-Rhodes University, Makanda, South Africa
Ana C Faltlhauser, FUEDEI-CONICET, Hurlingham, Argentina
Nicolás A Salinas, FUEDEI-CONICET, Hurlingham, Argentina
Megan Reid UF, Fort Lauderdale, USA
Laura Varone FUEDEI-CONICET, Hurlingham, Argentina
Andrés F Sánchez Restrepo, FUEDEI, Hurlingham, Argentina
Abstract
Classical biological control of invasive plants has traditionally focused on selecting natural enemies from the weed’s native range, prioritising host specificity and expected impact. While often effective, this approach may overlook the ecological, genetic, and microbial complexity shaping insect–plant interactions. Here, we examine Megamelus scutellaris, a South American planthopper released against water hyacinth (Pontederia crassipes) in the USA and South Africa. Although encouraging results were reported in South Africa, success elsewhere has been variable. We hypothesise that this variability reflects interacting factors such as local adaptation, genetic traits of both insect and plant, microbial symbiont composition, natural enemies (parasitoids), and differences in field deployment strategies. Our integrative framework combines SNP-based population genomics, symbiont profiling, morphometric comparisons between native and introduced populations, demographic performance, and parasitoid diversity and attack rates. We also compare biocontrol implementation strategies, from classical to augmentative. This study emphasises the need to integrate ecological, genetic, and microbial dimensions into biological control frameworks and shows how international collaboration and interregional comparisons can improve the effectiveness and resilience of weed biological control programs.
keywords
Biocontrol improvement
Integrative approach
Water hyacinth
Symbionts
Population genomics
Highlights
Beyond host specificity: embracing ecological and genetic complexity in biocontrol.
Megamelus scutellaris–water hyacinth: variable outcomes across regions, multiple drivers.
Integrative, collaborative approaches enhance weed biocontrol effectiveness worldwide.