Transient loss of olfactory recognition and innate olfactory behaviour preference in the aphid parasitoid Aphidius cole

MARTINEZ ANDRES; HARDIE JIM

Atenas, Grecia

Congreso; Entomophaga X; 2007

The affect of cold temperatures on the olfactory behaviour of the aphid parasitoid, Aphidius colemani is studied through a set of olfactometer bioassays to establish whether innate and learnt preferences can be distinguished in a plant-aphid-parasitoid system. Female parasitoids, reared on aphid hosts feeding on winter harvest a variety of Brussels sprout, underwent various short-term (< 24 h) temperature treatments (20, 5 and 0 °C) and their olfactory behaviour towards plant-leaf volatiles assessed. The results indicate that females exposed for 24 h to 5 °C are able to differentiate between the leaves of two Brassica varieties, but less consistently than in control treatments at 20 °C. On the other hand, 24 h at 0 °C does not affect preference for leaves of unencountered Brassica varieties or even wheat when contrasted with clean air, but wasps treated longer than 0.5 h at 0 °C were unable to distinguish between Brussels sprouts varieties. This change in behaviour correlates with the duration of the treatment and is only registered within 1 h of the cold treatment. When assays are completed after holding the insect at 20 °C for acclimation, odour discrimination is again evident. The present study suggests that cold temperature has affects on olfactory responses derived from learning processes leaving evidence underlying innate behaviours.mp;lt;!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-GB; mso-fareast-language:EN-GB;} @page Section1 {size:595.3pt 841.9pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --&amp;amp;amp;amp;gt;