Could movement of neonates from non-host plants affect the potential of polyculture to reduce crop colonisation by pest insects?

• Published in: Crop protection 2011-08, Vol.30 (8), p.1103-1105
• Main Authors: George, D.R., Collier, R., Whitfield, C., Port, G.
• Format: Article
• Language: English
• Subjects: Benign; crops; host plants; insect control; insect pests; integrated pest management; larvae; Larval movement; neonates; Non-host oviposition; pesticides; Plutella sp; Plutella xylostella; Polyculture
• ISSN: 0261-2194; 1873-6904
• DOI: 10.1016/j.cropro.2011.04.009

Existing and impending constraints to the use of synthetic pesticides, along with changing legislation in favour of an integrated approach to pest management, are driving uptake of ‘alternative’ approaches to pest control. Polyculture is one such approach, often relying upon the presence of non-host plants within the crop to reduce colonisation by pest insects. The diamondback moth, Plutella xylostella (L.), is known to oviposit on non-host plants and the present study showed that neonates were able to move relatively large distances, enabling them to relocate from non-host natal plants to nearby hosts. Although fewer larvae were found on host plants when they hatched on non-hosts, it is concluded that even a low level of re-location of neonates could potentially reduce the potential for polyculture to control this pest. It is proposed that non-host oviposition and neonate movement could explain why polyculture sometimes fails in controlling pest insects. ► Neonate Plutella xylostella moved from non-host natal plants to nearby hosts. ► Movement potential of neonates was relatively high on a benign surface. ► Neonate movement could reduce the potential of polyculture in pest management.