BioControl (2020) 65, 425-432

A. Honek, Z. Martinkova and S. Pekar (2020)
Threshold aphid population density for starting oviposition in Harmonia axyridis
BioControl 65 (4), 425-432
Abstract: The population density of Eucallipterus tiliae (L.) (Hemiptera: Aphididae) required for initiating oviposition in Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) was established in Tilia cordata Mill. (Dicotyledoneae: Tiliaceae) stands sampled weekly throughout the vegetative seasons of 2017–2019. The number of aphids per leaf area and oviposition in H. axyridis females were determined at each sampling session. Seasonal changes in aphid abundance and the presence of ovipositing females in natural populations varied across years but in all years H. axyridis started oviposition as soon as the aphid density increased above 10.2 aphids per ten sweeps, which equals 1.04 aphids per 100 cm² leaf area. These values exceed the threshold aphid density for starting oviposition in Coccinella septempunctata L. (Coleoptera: Coccinellidae), which is 0.40 aphids per 100 cm² leaf area. This difference is in line with H. axyridis preference for trees, host plants with complex architecture and hard to search, and preference of C. septempunctata for spatially simple herbs.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Alois Honek, Zdenka Martinkova, Stano Pekar

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.
	Eucallipterus tiliae	Lime tree/linden (Tilia)	Czech Republic
Coccinella septempunctata (predator)	Eucallipterus tiliae	Lime tree/linden (Tilia)	Czech Republic
Harmonia axyridis (predator)	Eucallipterus tiliae	Lime tree/linden (Tilia)	Czech Republic