Exploring maize genotypes for chemical attributes that promote the effectiveness of biological control agents (1997-2000)

Ms. Mary Fritsche, Université de Neuchâtel, Institut de Zoologie, 2007 Neuchâtel
Dr. D. Bergvinson, CIMMYT, Lisboa 27, Colonia Juarez, 06600 Mexico, D.F.

Goal / Objectives
The model plant is maize. It is an important crop worldwide, especially in developing countries, and it is ideal for laboratory as well as field studies. Much is known about this plant’s ability to initiate the release of parasitoid attractants after herbivore attack. One important new aspect of this project is that it will study the interactions between ancestral maize varieties and insects, and relate that to the interactions observed in cultivated maize.

The project will evaluate the extent to which parasitic insects are able to protect the plants from herbivore damage, and study the importance of volatiles released by various maize genotypes in determining this protection. The studies of maize will take place in its place of origin, Mexico, and three main questions are addressed:

• To what extent do maize plants benefit from the action of parasitoids.
• Under natural field conditions, do induced volatile emission indeed increase the likelyhood that herbivores get parasitized.
• Do maize genotypes that release more of the parasitoid attractands benefit more from the action of parasitoids.

These studies will contribute to a better understanding of the exploitability of naturally occuring tri-tophic level interactions between maize, herbivores, and the natrual enemies of herbivores. The ultimate objective is to use our results for safe and sustainable plant protection strategies, whereby pest insects are controlled in small farmer agriculture with the use of plants that are highly attractive to biological control agents.