Trap Cropping for Sustainable Crop Production Dr. Ayanava Majumdar Extension Entomologist Alabama Cooperative Extension System Gulf Coast Research & Extension Center 8300 State Hwy 104, Fairhope, Alabama 36532 Cell phone: 251-331-8416 PART 3A (discussion on key insect behavioral concepts)
Premise for using cultural pest control strategies
Set action thresholds: “Sighting a single pest does not always mean control is needed.” Think in economic terms!
Monitor and Identify Pests: “… monitoring and identification removes the possibility that pesticides will be used when they are not really needed...”
Prevention: “…using cultural methods…that can be very effective and cost-efficient and present little to no risk to people or the environment.”
Control: “Effective, less risky pest controls are chosen first, including highly targeted chemicals, such as pheromones to disrupt pest mating, or mechanical control, such as trapping or weeding.”
Source: USEPA http://www.epa.gov/pesticides/factsheets/ipm.htm USEPA’s Four-tiered Model of IPM
Multiple cropping for Diverse Habitat
Host plant quality hypo.: plant species can interact in a way to reduce attractiveness to pest (Theunissen 1994)
IPM Era (1970-1990s) Natural enemies hypo. (Root 1973): cultural control tactics can conserve or increase natural enemies (Hummel et al. 2002, Peachey et al. 2002, Schmidt et al. 2004, Carmona & Landis 2003) Diverse background moderates insect behavior (1960 – 1985): insects get confused or separated! Post-IPM Era (1990-) Pre-IPM Era (-1970s) Resource concentration hypo.: herbivores (=pests) remain in an area where essential resources are concentrated (Root 1973)
What is a trap cropping?
Trap cropping is the planting of an attractive trap crop to protect the main crop (PAN Germany, 2009). Trap crop may or may not be harvestable.
Trap cropping is a production system that exploits insect behavior by continuously providing food plants in the preferred stage (Grossman 2008)
“ Trap cropping is a special case of multiple cropping.” “ Presence of second crop in the vicinity of principal crop diverts a pest, which would otherwise attack the principal crop” (Van der meer 1981)
Why should you use trap crops? Combined use of cultural control + Insecticides = IPM approach Trap crop New insecticide Corn earworm devastated sunflower (trap crop) but stayed away from peanuts Image source: ICRISAT, India
Host finding & oviposition behavior
Plant color, odor, shape (acts at a distance)
Texture, phytochemicals, treatments (acts after landing)
Note: Adult females make the decision to oviposit & starts a primary infestation!
How trap cropping works? Various behavioral theories that could explain success of trap crops.
Visual camouflage (Smith 1969)
Masking of host plant odor (Tahvanainen & Root 1972)