Cercospora Leafspot Management Decisions: An Economic Analysis of a Weather-Based Strategy for Timing Fungicide Applications^1,,2

The average savings in peanut leafspot control costs from use of the Virginia leafspot advisory program versus the conventional 14-day application schedule ranged from $70.95/ha for cupric hydroxide plus sulfur to $97.39/ha for benomyl plus sulfur in 1980–1983. Increases in net returns from use of benomyl plus sulfur, chlorothalonil, or cupric hydroxide plus sulfur with the leafspot advisory were attributed to increases in yield as well as decreased control costs. Average annual increases in net return from use of the advisory in comparison to standard 14-day programs of the same fungicides were $259.99, $200.21, $192.55, and $220.57/ha for 1980, 1981, 1982, and 1983, respectively. Annual variation in economic returns was similar for all fungicides and for both application schedules tested.