Assessment of patch quality by aphidophagous ladybirds: Laboratory study on the minimum density of aphids required for oviposition

0371949 - ÚVGZ 2012 RIV CZ eng J - Journal Article
Das, B. C. - Dixon, Anthony F. G.
Assessment of patch quality by aphidophagous ladybirds: Laboratory study on the minimum density of aphids required for oviposition.
European Journal of Environmental Sciences. Roč. 1, č. 1 (2011), s. 57-60. ISSN 1805-0174
R&D Projects: GA MŠMT LC06073; GA MŠMT(CZ) ED1.1.00/02.0073
Institutional research plan: CEZ:AV0Z60870520
Keywords : Adalia bipunctata * Aphididae * arrestant * Coccinellidae * cues for oviposition * honeydew * minimum aphid density * patch quality * predator
Subject RIV: EH - Ecology, Behaviour

Many studies indicate that there is a density of aphids below which ladybirds are unlikely to lay eggs. This is adaptive as theory indicates that a certain minimum population density of aphids is required if hatchling larvae are to survive. The responses of gravid females of the two spot ladybird, Adalia bipunctata (L.) (Coleoptera: Coccinellidae), recorded over a period of an hour, to colonies of 5 and 50 pea aphids on bean plants and similar plants each previously infested with the same number of aphids for 48 hours were determined. Proportionally more of the ladybirds on plants with 50 aphids or that were previously infested with the same number of aphids for 48 hours laid eggs and larger clusters of eggs, and were less active than those on plants that were infested with or had previously been infested with five aphids. That is, gravid females showed similar oviposition and activity responses to aphid abundance and different levels of honeydew contamination. This indicates that honeydew contamination may be an important cue used by ladybirds when locating and assessing the abundance of prey in aphid colonies.
Permanent Link: http://hdl.handle.net/11104/0205355