Skip to main content
ARS Home » Research » Publications at this Location » Publication #76962
Title: UNDERSTANDING HOW PARASITOIDS BALANCE FOOD AND HOST NEEDS: IMPORTANCE FOR SUCCESSFUL BIOLOGICAL CONTROL

Author
item Lewis, Wallace
item STAPEL, J. - UNIV. OF GA, ENTOMOLOGY
item CORTESERO, ANNE - UNIV. OF GA, ENTOMOLOGY
item TAKASU, KEIJI - KOBE UNIVERSITY, JAPAN

Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/1/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: Plant feeding insects are costly pests of agricultural crops. Resistance and residue problems with conventional pesticides have caused scientists to seek better ways to use natural enemies for the control of insect pests. Understanding natural enemies and how they interact with crops and crop pests is essential for their dependable use in pest control. ARS scientists at Tifton, Georgia are seeking to better understand the foraging behavior of parasitic wasps, which attack the caterpillar stage of the bollworm, armyworm and other pests. The adult stage of these wasps are free living and require nectar and/or pollen for food. Greenhouse and field studies showed that the availability of proper quality, quantity and distribution of adult food is crucial for effective performance by wasps as biological control agents. This information can be used to design ways for manipulating the retention and efficiency of beneficial wasps in target locations.

Technical Abstract: Adult parasitoids must not only find hosts for reproductive purposes but also locate food to meet their short-term nutritional needs. A knowledge of how females deal with the often competing needs for these two vital resources is essential for understanding parasitoid foraging strategies. Studies show that availability and accessibility of food sources such as nectar or honeydew in a target area strongly affect their retention and host-finding efficacy. For parasitoids to maintain high reproductive success it is important that disruption of their host foraging process is minimal so that most of their time and energy can be allocated to finding hosts. The use of olfactory and visual cues from plants, usually enhanced by learning, helps minimize this disruption and plays important and sometimes interacting roles in their searching for food and hosts. Thus, the provision of food sources such as floral and extrafloral nectar by plants along with associated foraging signals plays a crucial role in the tritrophic interplay among plants, herbivores and parasitoids. A broader understanding of tritrophic level interactions that encompasses parasitoid food considerations can enhance our ability to design effective biological control strategies.