Home About us MoEF Contact us Sitemap Tamil Website  
About Envis
Whats New
Research on Microbes
Microbiology Experts
Online Submission

Site Visitors

blog tracking

Agriculture, Ecosystems & Environment
Vol. 164,
2013; Page: 183 - 189

Natural regulation of Delia radicum in organic cabbage production

Nicolai V. Meyling, Søren Navntoft, Holger Philipsen, Kristian Thorup-Kristensen, Jørgen Eilenberg

Department of Agriculture and Ecology, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.


In a field experiment, we evaluated effects of three different organic white cabbage-cropping systems (O1, O2, O3) on the cabbage root fly, Delia radicum, and its egg predators and pupal parasitoids over 3 years. The three systems all complied with regulations for organic production, but varied in external nutrient input and N-recycling, and were compared to a conventionally farmed control. One organic system (O3) included an intercropped strip of green manure between crop rows. Oviposition by D. radicum was generally not reduced in organic cropping systems. However, higher pupae/egg ratios were observed in the conventional compared to all organic systems, indicating that immature survival from oviposition to pupation was reduced under all the three organic farming practices. In organic system O2 most small coleopteran predators were recorded, but predation on fly eggs was not significantly higher in organic treatments. Pupal parasitization rates ranged from 26.5% to 59.5%, but no significant differences among farming systems were found. Although reduced D. radicum survival could not be attributed solely to natural enemies, the results indicated that organic farming practices in general contribute to the suppression of belowground pests in cabbage production.

Keywords: Pest management; Organic fertilizer; Trybliographa rapae; Staphylinidae; Carabidae



Copyright © 2005 ENVIS Centre ! All rights reserved
This site is optimized for 1024 x 768 screen resolution