PARENT SESSION
Thursday, August 10, 5:00-6:30 pm
Poster Session 24 - Modeling, statistics, and spatial analysis
Exhibit Hall, Ballroom Level, Cook Convention Center

Spatial patterns of infection of two plant pathogens with different transmission modes.

Finch, Debra^*,1, Alexander, Helen ¹, ¹ University of Kansas, Lawrence, KS

ABSTRACT- Different pathogens vary greatly in their mode of transmission, which would be predicted to affect their spatial distribution, and thus potentially their impact on the ecology and evolution of plant populations. The woodland sedge, Carex blanda, is infected by two fungi, both by a floral smut pathogen, Anthracoidea blanda, and a foliar rust, Puccinia sp. The smut can only infect plants during a narrow period of time in the spring when flowers are at an early stage of development; in contrast, the rust can infect plants for a much longer time when leaves are available. Using 31 sites sampled across Kansas, we found that the smut is absent from many western isolated plant populations, consistent with its more limited mode of transmission, while the rust is found in nearly all populations. Within these sites, areas with higher plant densities were more likely to have both rust and smut infection. At both large and small spatial scales, infection of the rust and smut appear independent of each other. Patterns of infection are important to quantify because of their likely effect on subsequent spread of disease within and between populations and plant competitive interactions.

Key words: plant disease ecology, smut and rust fungi, spatial patterns at different scales