Eb. Mondor et Jl. Warren, Unconditioned and conditioned responses to colour in the predatory coccinellid, Harmonia axyridis (Coleoptera : Coccinellidae), EUR J ENTOM, 97(4), 2000, pp. 463-467
We determined if mature ladybirds use colour to initially find suitable hos
t plants. We also determined whether ladybird beetles are capable of associ
ating characteristics such as colour with the presence of prey. Here, we sh
ow that the multicoloured Asian ladybird beetle, Harmonia axyridis, has a d
ifferential response to yellow compared to green colours. Naive ladybirds,
of both sexes, make significantly more visits and spend more time on yellow
vs, green coloured pillars. After pairing yellow and green colours with th
e presence or absence of aphid prey, ladybirds alter their foraging behavio
ur. Beetles conditioned to having food on both pillar colours exhibited the
same responses as naive beetles, while beetles conditioned to only yellow
or green pillars did not exhibit a preference for visiting or spending time
on different colours. However, there was a trend towards females spending
more time on pillar colours on which they received reinforcement, and males
spending more time foraging on colours opposite to that which they were re
inforced. Thus, H. axyridis is capable of responding to cues such as colour
, and its foraging behaviour can be altered as a result of prior experience
.