Dispersal and spatial distribution of western corn rootworm larvae in relation to root phenology
Article first published online: 8 MAY 2012
© 2012 The Authors. Agricultural and Forest Entomology © 2012 The Royal Entomological Society
Agricultural and Forest Entomology
Volume 14, Issue 4, pages 331–339, November 2012
How to Cite
Schumann, M. and Vidal, S. (2012), Dispersal and spatial distribution of western corn rootworm larvae in relation to root phenology. Agricultural and Forest Entomology, 14: 331–339. doi: 10.1111/j.1461-9563.2012.00573.x
- Issue published online: 15 OCT 2012
- Article first published online: 8 MAY 2012
- Accepted 25 February 2012
- Below ground distribution;
- Diabrotica virgifera virgifera;
- root herbivore;
- soil stratification;
- Zea mays
- 1Despite the increasing economic importance of root feeding pests such as the western corn rootworm (WCR) Diabrotica virgifera virgifera, basic parameters about their below ground biology are only partly understood. The present study investigated the dispersal and distribution of WCR larvae in the maize root system during their development at two growth stages of maize (BBCH 13–14 and BBCH 17–18).
- 2Dispersal of the WCR larvae increased as they developed; the larvae moved off their original place of emergence and into deeper soil layers. Overall, changes in the horizontal distribution of the larvae were more extensive than changes in the vertical distribution.
- 3The spatial analysis of distance indices revealed that the larvae had an aggregative distribution throughout their development. The feeding site of larvae in the root system was determined by the stage of larval development. Initially, WCR larvae started feeding in close proximity to their emergence location and moved to more developed root tissue towards the end of their development.
- 4Differences in root phenology mainly influenced the distribution of the larvae at the end of their development, when larvae exhibited increased vertical movement at a later growth stage of maize.
- 5The mechanisms of these distributional changes and the implications for the management of WCR larvae are discussed, especially with regard to chemical control, because fewer larvae are expected to be targeted at a later growth stage of maize.