Comparison of Meteorological and Standardized Timings of Fungicide Applications for Soybean Disease Control. P. A. Backman, Department of Botany, Plant Pathology, and Microbiology, Auburn University Agricultural Experiment Station, Auburn University, AL 36849. M. A. Crawford, and J. M. Hammond, Department of Botany, Plant Pathology, and Microbiology, Auburn University Agricultural Experiment Station, Auburn University, AL 36849. Plant Dis. 68:44-46. Accepted for publication 25 July 1983. Copyright 1984 The American Phytopathological Society. DOI: 10.1094/PD-68-44.

Results from soybean foliar disease-control tests conducted over 4 yr indicate that the standard two-spray program required 33% more fungicide applications than an application-timing system based on rainfall frequency. Fungicide applications for the meteorological system were made to more appropriately coincide with infection periods; numbers of fungicide applications ranged from zero to three. The standard program did not return the cost of treatment 50% of the time, whereas the meteorological system always resulted in a positive dollar return over the cost of control.