Print PageCrop diversification and habitat manipulation can be effective and sustainable strategies for pest control in agricultural systems. Trap cropping, the use of attractive host plants to pull pests off a cash crop, is one such strategy. While simulation models have been used to determine the characteristics of insects and plants important for maximizing the efficacy of trap cropping, their complexity makes it difficult to tease apart complex relationships and provide general conclusions. Therefore, we developed a simpler model in order to understand how a trap crop’s spatial configuration within a field, its attractiveness, and its ability to retain insects affects pest density on a cash crop.
Results/Conclusions
The model predicts that the relationship between these parameters and pest density is nonlinear. When the attractiveness of a trap crop is low, small gains in attraction greatly decrease cash crop pest density. When attractiveness is high, increases in attractiveness have little effect. The opposite is true for trap crop retention. When retention is low, changes in retention have little effect on pest density, but when retention is high, changes in retention have a large effect. Clumping trap crops close together can lessen this nonlinear relationship, and also reduce equilibrium pest densities. However, this depends on the amount of movement in the system. These results suggest that several pest management practices that are effective on their own might undermine the efficacy of a functioning trap crop, while other management practices may work synergistically with trap cropping.
