The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader).

If you would like more information about how to print, save, and work with PDFs, Highwire Press provides a helpful Frequently Asked Questions about PDFs.

Alternatively, you can download the PDF file directly to your computer, from where it can be opened using a PDF reader. To download the PDF, click the Download link above.

Fullscreen Fullscreen Off


A study was conducted to assess the functional response of different life stages of the predacious coccinellid, Adalia tetraspilota (Hope) feeding on various densities of cabbage aphid, Brevicoryne brassicae (L.) under controlled conditions. It revealed that all stages of A. tetraspilota exhibit Type II functional response curve (a curvilinear rise to plateau) as B. brassicae densities increase and the curve predicted by Holling's disk equation did not differ significantly from the observed functional response curve. The fourth instar larva consumed more aphids (28.40 aphids / day) followed by adult female (25.06 aphids / day), third instar larva (24.06 aphids / day), second instar larva (21.73 aphids/ day), adult male (20.06 aphids/day) and first instar (13.06 aphid /day). The maximum search rate with shortest handling time was recorded for fourth instar larva (0.6383) followed by adult female (0.6264). The results suggest that the fourth instar larva are best suited for field releases for the management of B. brassicae. However, further field experiments are needed for confirming its potential.

Keywords

Adalia tetraspilota, Aphididae, Brevicoryne brassicae, Coccinellidae, Functional Response, Handling Time, Predation and Search Rates.
User
Notifications