Work

Volatile-mediated interactions between cereal aphids and Fusarium graminearum shape wheat susceptibility to pest and pathogen induced biotic stress

Year: 2025

Type: article

Abstract: Aphids and Fusarium graminearum are major biotic threats to wheat, yet little is known about their interactions on their shared host. Here, we show that a deoxynivalenol (DON)-producing isolate of F. graminearum, causing Fusarium head blight (FHB), modifies wheat volatile emissions to differentially affect the behaviour, locomotion and fitness of the cereal aphids, Rhopalosiphum padi and Sitobion avenae. Using pre- and post-alighting behavioural assays, volatile profiling, olfactometry and life history trait analyses, we reveal that pathogen-induced volatile organic compounds attract winged R. padi but repel S. avenae, thereby forming a novel mutualistic-antagonistic pest-pathogen complex. Heneicosane, a key semiochemical, elevated in the infected FHB-susceptible cultivar Gallant, acted as a kairomone for R. padi and as a deterrent allomone for S. avenae, altering aphid host selection and fecundity. In direct co-localisation, F. graminearum reduced the fitness of both aphid species, but increased mycotoxin production in response to S. avenae, consistent with competitive exclusion. In contrast, distal interactions revealed that R. padi increased pathogen virulence, fungal biomass, and accumulation of DON, 15-acetyl-DON, and nivalenol while benefiting from enhanced reproduction. These synergistic interactions reduced the effectiveness of genetic FHB-resistance in Sumai3, suggesting aphid-induced systemic suppression of defence. Our findings highlight the importance of volatile-mediated co-evolution between pathogens and insect pests and reveal hidden mutualism between R. padi and F. graminearum with significant implications for Integrated Pest and Disease Management. Under climate change scenarios favouring increased aphid and Fusarium incidence, pest-pathogen cooperation may become a critical factor in crop vulnerability and disease forecasting.

Source: Plant Stress

DOI: 10.1016/j.stress.2025.101116

Authors: Samuel Asamoah, Amma L. Simon, Ilma A. Qonaah, Dong-Hyun Kim, Toby J.A. Bruce, Rumiana V. Ray

Institutions: University of Nottingham, Keele University

Language: English

Topic: Insect-Plant Interactions and Control

Subfield: Insect Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $2,310