Work

Characterizing fungal community shifts associated with Amauromyza karli Hendel (Diptera: Agromyzidae) infestation in quinoa

Year: 2026

Type: article

Abstract: Introduction Fungal communities are central elements of phytobiomes, yet their roles in mediating plant-insect interactions remain poorly understood. Here, we addressed this knowledge gap in quinoa, which has recently suffered significant losses due to a stem-boring pest. Methods We used culture-based isolation from stems and amplicon-based profiling of rhizosphere soils to characterize quinoa-associated fungi across six site-year combinations in Colorado and to relate community patterns to abundance of stem-boring fly Amauromyza karli Hendel (Diptera: Agromyzidae). Results Eighteen stem endophytes dominated by Ascomycota were isolated. Soil sequencing resolved 23 core amplicon sequence variants detected across all site-years; the core was primarily Ascomycota, with Fusarium spp., Alternaria spp., and Plectosphaerella spp. comprising over half of relative abundance of the entire community. Alpha diversity (richness, Shannon, inverse Simpson) differed significantly among site-years, and beta-diversity analyses revealed clustering by site and year. Abundance of adult A. karli was correlated positively with soil fungal richness and Shannon diversity and was also significantly associated with differences in community composition. Indicator and differential-abundance analyses identified taxa linked to low fly abundance (e.g., Cladosporium herbarum , Alternaria spp.) versus high abundance (e.g., Fusarium solani, Microdochium spp.). Fusarium spp., and Alternaria spp. were more prevalent in fields with high larval abundance, whereas antagonistic endophytes such as Gibellulopsis piscis and Heydenia spp. dominated in low-abundance fields. Discussion These results indicated that community composition impacted pest pressure, with pathogenic fungi coinciding with higher fly abundance and entomopathogenic fungi enriched where larval pressure was lower. These findings identify candidate taxa for microbiome-informed integrated pest management and underscore the potential of site-specific practices (e.g., intercrops, organic amendments) to foster fungal communities that enhance quinoa resilience.

Source: Frontiers in Plant Science

DOI: 10.3389/fpls.2026.1741091

Authors: Neha Panwar, Jane E. Stewart, Jorge R. Ibarra Caballero, Adrianna Szczepaniec

Institution: Colorado State University

Language: English

Topic: Plant and fungal interactions

Subfield: Ecology, Evolution, Behavior and Systematics

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Zero hunger, Life on land

Open Access status: gold

Estimated APC paid: $3,801