CAA: Domestication and Agronomic Selection Influences on Maize Defense Against a Specialist Herbivore

Texas A&M Agrilife Research, College Station TX

Investigators

Abstract

This project addresses the ecological and evolutionary bases for the acquisition by corn, Zea mays ssp. Mays, of the herbivore, Dalbulus maidis (aka corn leafhopper), as a specialist pest. Specifically, the project will examine how domestication and agronomic selection for high yield and other traits of human interest may have weakened corn's defenses against the corn leafhopper, through comparative studies of corn's perennial ancestor Z. diploperennis, its annual ancestor Z. mays ssp. parviglumis, a corn landrace, and modern (hybrid) corn. The research will integrate laboratory and field research, taking advantage of study sites in central Mexico where the ancestral species of domestic corn occur. The research will elaborate the relationships between yield and herbivore defenses in the complex of corn and its less domesticated relatives and will explore the specific anatomical, morphological, and chemical defenses of each. The project will contribute to our understanding of the susceptibility of agricultural plants to pests and of the mechanisms by which herbivores become pests of agricultural crops. An improved understanding of these processes will contribute to developing pest management strategies with greater ecological and evolutionary sustainability than those currently available. The project will contribute to increasing traditionally under-represented groups in science careers through training and mentoring of two MS students from minority groups.