Characterization of the Omnivorous Lygus lineolaris Diet in a Strawberry Field by Metataxonomy

TL;DR

This study uses DNA analysis to show that the pest Lygus lineolaris eats mostly plants but also some animals, with a new way to measure its diet.

Contribution

The paper introduces a novel coefficient of omnivory to quantify feeding behavior in omnivorous species.

Findings

Lygus lineolaris has a diet of 475 host taxa, including 441 plants and 34 prey species.

The species shows a strong herbivorous bias with a coefficient of omnivory of 0.833.

Diet varies seasonally and by sex, with females showing increased zoophagy during reproduction.

Abstract

Lygus lineolaris
is a highly polyphagous pest that impacts key crops such as strawberries, making an understanding of its feeding behavior critical for developing effective management strategies. Using metataxonomy, this study examined the dietary breadth of
L. lineolaris
in a commercial strawberry field in Quebec, revealing an extensive and diverse omnivorous diet. The multiprimer approach, combined with validation samples, ensured high taxonomic resolution and accuracy. We expanded the documented list of
L. lineolaris
host taxa to 475, including 441 plants and 34 prey species, with 51 taxa unique to this research, comprising eight new plant hosts and five prey species. Molecular evidence confirmed active ingestion, underscoring its omnivorous behavior with a predominantly herbivorous tendency. Notably, 70% of individuals fed exclusively on plants, 20% exhibited omnivory, and only 4% were strictly zoophagous. To quantify the level of phytozoophagy in omnivorous species, we propose a novel coefficient of omnivory (CO), calculated as CO = P/(P + Z), where P and Z represent the number of individuals with molecular evidence of phytophagy and zoophagy, respectively. With a CO of 0.833 (95% CI: 0.77–0.90),
L. lineolaris
demonstrates a strong bias toward plant feeding. Diet composition varied seasonally and between sexes, with females showing increased zoophagy during reproductive periods. These findings highlight
L. lineolaris
's dietary flexibility and resilience, providing critical insights into its feeding ecology and food web interactions to inform targeted integrated pest management strategies tailored to its omnivorous nature.

This study employs metataxonomy to reveal the extensive omnivorous diet of
Lygus lineolaris
in a strawberry field, identifying 475 host taxa and confirming active ingestion across plant and prey sources. We introduce a novel coefficient of omnivory, demonstrating the species' strong herbivorous bias while highlighting its dietary flexibility and seasonal, sex‐based variations. These findings enhance understanding of
L. lineolaris
's feeding ecology and inform targeted pest management strategies.

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