Fermer

Mickaël Gaillard

Research interests

Maize (Zea mays subsp. mays) is one of the most important crop in the world. It has been domesticated in modern day Mexico about 9,000 years ago from a plant called teosinte (Zea mays subsp. parviglumis). Artificial selection changed a lot of genetic, chemical and morphological characteristics of maize to enhance its seed quality and its production. However, like many other plants, it appears that maize domestication weakened its natural defenses against pest insects. Amongst many other traits, plants can produce secondary metabolites to defend against herbivores. But some commercial maize lines lost the ability to produce some key defensive compounds such as ß-caryophyllene, an important compound used to attract natural enemies of the pests.

The aim of my project is to get an overview of the consequences of maize domestication for various insects regarding the weakened defenses, using several commercial maize lines and natural populations of teosinte. This part of the project involves different insect feeding guilds as well as different degrees of host specialization from the insects.

In a second time the aim is also to find out what are the major changes in maize secondary metabolites compared to its ancestor to explain the observed results in the first part of the project. To tackle this issue I’m using general metabolomics analysis in parallel with targeted analysis on benzoxazinoid compounds that are well known to play a role in maize defenses.

Finally I am am also interested in finding what are the key parts of teosinte genome for natural defenses that could have been lost during the process of domestication. For this I am working with maize lines (B73 background) that are including an introgressed part of teosinte genome. I’m trying to observe differential effects of this lines on insect’s larval growth to spot the important portion of teosinte genome in terms of defense.

This project is bringing biological, chemical and genetic tools together in an attempt to understand better how artificial selection affected maize and how it also affected insects feeding on it.

Publications

Mickaël Gaillard

Assistant doctorant

 

mickael.gaillard@unine.ch

+41 32 718 31 62

Bureau D123