PARENT SESSION
Poster Session #32: Plant Ecology I.
Wednesday, August 8, 2001. Presentation from 3:30 PM to 5:00 PM. Exhibition Hall
147
Effects of species, leaf position, and soil fertility on foliar disease in a tallgrass prairie.
Emry, Jason1, Moody-Weis, Jennifer1, Rabas, Alicia1, Smith, Val1, Foster, Bryan1, Petersen, Venessa1, 1
ABSTRACT- Plant pathogens are widely studied in the context of agricultural applications and forest management. Though some studies have investigated disease in natural populations, they have mostly focused on the role of disease resistance in regulating pathogen and host populations. The purpose of this study was to determine how plant species identity, soil fertility, and leaf position (position in the canopy) affect the incidence and infection levels of foliar pathogens on four species commonly found in the tallgrass prairie in northeastern Kansas. ANOVA revealed that infection level was significantly affected by leaf position, with lower leaves having up to four times more diseased tissue than upper leaves. Infection levels were similar in Andropogon gerardii, Sorghastrum nutans, and Solidago canadensis but were nearly twice as high in Setaria faberi. Fertilization rate had no effect on disease levels in any of the species studied in 2000. Future studies should address whether the influence of leaf position is the result of differences in leaf age or in microclimate within the canopy. A long-term goal is to integrate these results with those from an ongoing study of the effects of tissue nutrient status on the incidence of foliar pathogens.
KEY WORDS: disease, prairie