Entomologia Experimentalis et Applicata (1998) 86, 109-118

Christine A. Armer, Robert N. Wiedenmann and Daniel R. Bush (1998)
Plant feeding site selection on soybean by the facultatively phytophagous predator Orius insidiosus
Entomologia Experimentalis et Applicata 86 (2), 109-118
Abstract: Experiments were conducted to test whether the facultatively phytophagous predator Orius insidiosus (Say) (Heteroptera: Anthocoridae) ingested phloem, xylem or mesophyll contents from soybean plants (Glycine max L.). Potential uptake of phloem sap was examined by radiolabeling photosynthate with ¹⁴CO₂ and then measuring the accumulation of radiolabeled metabolites in feeding animals. Most O. insidiosus feeding on radiolabeled plants ingested no or very low levels of label; only 3% ingested small amounts of label, indicating the experimental insects fed very little, if at all, on the phloem. In contrast, well known phloem feeding insects used as positive controls accumulated substantial levels of labeled metabolites after feeding on known host plants. O. insidiosus did feed on xylem contents, as shown by ingestion of safranin-labeled xylem fluid. A few of the insects showed signs of feeding on the mesophyll, as indicated by the presence of chloroplasts in the gut. However, the small diameter of the food canal may cause limited passage of chloroplasts, which would contribute to an underestimation of the frequency of mesophyll feeding. Some radiolabeled metabolites remain in the mesophyll so those insects that ingested low levels of radiolabel probably ingested label from the mesophyll, which supports the notion that some level of mesophyll feeding occurred. Feeding site determines the nutrients ingested during phytophagy. These insects obtain water from the xylem, and may ingest small amounts of starches, sugars, and amino acids from the mesophyll. The results suggest that facultative phytophagy by this heteropteran predator primarily provides the insect with water, but also may provide some nutrients that supplement a prey diet and help the predator survive periods when prey are scarce.
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Link to article at publishers website
Database assignments for author(s): Christine A. Armer

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
Orius insidiosus (predator)