Please use this identifier to cite or link to this item:
Title: Effects of carbon dioxide on the searching behaviour of the root-feeding clover weevil 'Sitona lepidus': (Coleoptera: Curculionidae)
Contributor(s): Johnson, S N (author); Zhang, X X (author); Crawford, J W (author); Gregory, P J (author); Hix, N J (author); Jarvis, S C (author); Murray, P J (author); Young, Iain (author)
Publication Date: 2006
Handle Link:
Abstract: The respiratory emission of CO₂ from roots is frequently proposed as an attractant that allows soil-dwelling insects to locate host plant roots, but this role has recently become less certain. CO₂ is emitted from many sources other than roots, so does not necessarily indicate the presence of host plants, and because of the high density of roots in the upper soil layers, spatial gradients may not always be perceptible by soil-dwelling insects. The role of CO₂ in host location was investigated using the clover root weevil 'Sitona lepidus' Gyllenhall and its host plant white clover ('Trifolium repens' L.) as a model system. Rhizochamber experiments showed that CO₂ concentrations were approximately 1000ppm around the roots of white clover, but significantly decreased with increasing distance from roots. In behavioural experiments, no evidence was found for any attraction by 'S. lepidus' larvae to point emissions of CO₂, regardless of emission rates. Fewer than 15% of larvae were attracted to point emissions of CO₂, compared with a control response of 17%. However, fractal analysis of movement paths in constant CO₂ concentrations demonstrated that searching by 'S. lepidus' larvae significantly intensified when they experienced CO₂ concentrations similar to those found around the roots of white clover (i.e. 1000 ppm). It is suggested that respiratory emissions of CO₂ may act as a ‘search trigger’ for 'S. lepidus', whereby it induces larvae to search a smaller area more intensively, in order to detect location cues that are more specific to their host plant.
Publication Type: Journal Article
Source of Publication: Bulletin of Entomological Research, v.96, p. 361-366
Publisher: Cambridge University Press
Place of Publication: United Kingdom
ISSN: 1475-2670
Field of Research (FOR): 050303 Soil Biology
050305 Soil Physics
050399 Soil Sciences not elsewhere classified
060208 Terrestrial Ecology
Peer Reviewed: Yes
HERDC Category Description: C1 Refereed Article in a Scholarly Journal
Other Links:
Statistics to Oct 2018: Visitors: 611
Views: 820
Downloads: 0
Appears in Collections:Journal Article

Files in This Item:
2 files
File Description SizeFormat 
Show full item record

Page view(s)

checked on Mar 1, 2019
Google Media

Google ScholarTM






Items in Research UNE are protected by copyright, with all rights reserved, unless otherwise indicated.