Determining Fungicide Degradation On Golf Course Turfgrass Under Winter Conditions Using Commercially Available ELISA Kits.

Microdochium nivale is an important winter pathogen of turfgrass in temperate climates. Traditionally, a single fungicide application made in the fall is expected to control winter turfgrass pathogens until the spring. In the absence of snow cover, fungicides applied in the fall can break down and fail to provide protection to the plant. Measuring the fungicide concentration on the leaf blade allows turfgrass managers to determine if adequate disease protection remains and if another fungicide application is required. In the past, accurate fungicide concentration analysis has been obtained through methods such as high performance light chromatography. These methods are effective but not conducive to analyzing large numbers of samples due to the time and cost required. Commercially available enzyme-linked immunosorbent assay (ELISA) kits produced by Horiba Ltd can determine fungicide concentrations on fruits and grains quickly and accurately for a large number of samples. Significant changes to the method had to be made for use on turfgrass. Preliminary testing on turfgrass has shown that it can effectively determine differences in the degradation rate of the fungicides iprodione and chlorothalonil under snow cover and in the absence of snow. Continued study of ELISA kits on turfgrass can help determine the rate of fungicide breakdown under winter conditions with the goal of making more accurate and effective fungicide applications in the future.