The cool temperatures of fall are approaching, but it is springtime for Jorge Mena-Alí.
The visiting assistant professor of biology recently embarked on a research project examining the evolution and ecology of host-pathogen interactions, using the spring beauty family (Portulacaceae) as a vehicle of study. Funded by a $173,000 grant from the National Science Foundation, the project is titled "Disease as a Driver of Diversification in Life History, Pathogenicity and Reproductive Stages."
"The plant system provides us an opportunity to understand what happens in a broad sense across species," says Mena-Alí, whose project aims to identify factors driving the evolution of contrasting disease strategies among closely related pathogens. "The same concept applies to humans, crops, insects and animals. But the nice thing about plants is that they are easy to grow, and we can do inoculations without ethical concerns."
Mena-Alí's project stems from an increasing interest in understanding the dynamics of disease transmission across species, particularly as recent infections such as HIV, avian influenza and H1N1 have directly affected human populations. Although the interactions between pathogens and hosts are usually treated as static, Mena-Alí says that closely related pathogens often show striking differences in virulence and transmission between hosts.
In nature, the pathogen that causes smut disease (Microbotryum spp) moves from plant to plant by hitching rides on pollinators such as bees and butterflies. In a previous study looking at smut disease in the closely related carnation family, Mena-AlÃ found that the disease affects perennials to the greatest degree, halting the plants' ability to produce seeds in the years after infection. Annuals, which complete their life cycle in one year, are safe from the disease.
"With maximum virulence, the plant is attacked and is finished," says Mena-Alí. "With muted virulence, the plant becomes infected but still has some reproductive capability. It might still produce seeds, but they will be infected. It's like the plague versus the normal flu." Mena-Alí will use the grant to analyze this variability in virulence.
Mena-Alí, who serves as the point person on the project, will also collaborate with Jamie Blair, assistant professor of biology at the College; Michael Hood, assistant professor of biology at Amherst College; Christopher Hardy, assistant professor of biology at Millersville University; and Matthew Ferrari, biology research associate at Penn State University.
"The project borrows from a variety of fields, including population genetics, informatics and ecology," says Mena-Alí. "We want to convey to students that you don't get training in one area. You have to have a multidisciplinary approach. The complexity of problems forces you to have a broad viewpoint. It's what makes this project interesting to a lot of people."