Quantifying the effects of insectary plants on the abundance of natural enemies : implications for controlling insect pests in an organic cabbage eco-system
Abstract
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Farmscaping is an ecological approach to pest management that involves planting non-crop plants to boost natural enemy abundance and suppress pest populations. For example, establishing flowering plants or 'insectary plants' in and around crop fields to provide resources for natural enemies is a strategy to enhance the biological control of crop pests. In addition, planting attractive 'trap crop' plants near fields can lure pests away from the crop and concentrate them in a limited area for control. The goal of this study was to contribute to the development of an effective farmscaping strategy for the management of cabbage pests in Missouri. The first objective was to compare the effectiveness of different insectary plant species by quantifying the abundance and diversity of natural enemies visiting the plants. The second objective was to assess the viability of integrating the use of insectary plants with trap cropping as a sustainable method of eliminating the pests from the trap crops. We found that among seven insectary plant species, buckwheat (Fagopyrum esculentum) and sweet alyssum (Lobularia maritima) attracted the most abundant and diverse assemblages of natural enemies. When integrated with trap crops, insectary plants increased the abundance of natural enemies on the trap crop, leading to greater pest suppression on the cash crop for specific herbivores, such as the cross-striped cabbageworm, Evergestis rimosalis. We conclude that managing the habitat and diversifying the crops to enhance the recruitment and residency of natural enemies when trap crops and insectary plants are combined can be an effective ecologically-based Integrated Pest Management approach.
Degree
M.S.
Thesis Department
Rights
Access is limited to the campuses of the University of Missouri.