pnut pnut Peanut Science 0095-3679 0095-3679 American Peanut Research and Education Society 10.3146/pnut.12.2.0009 10.3146/i0095-3679-12-2-9 Articles Cercospora Leafspot Management Decisions: An Economic Analysis of a Weather-Based Strategy for Timing Fungicide Applications1,,2 C. S Johnson , P. M Phipps , and M. K Beute 3 Former Graduate Research Assistant, Department of Plant Pathology, North Carolina State University, Raleigh, N. C. 27695–7616, Associate Professor of plant pathology, Tidewater Research and Continuing Education Center, Suffolk, Va. 23437, and Professor, Department of Plant Pathology, North Carolina State University, Raleigh, N. C. 27695–7616

1Paper No. 9856 of the Journal Series of the North Carolina Agricultural Research Service, Raleigh, N. C. 27695–7601.

2The use of trade names in this publication does not imply endorsement by the North Carolina Agricutural Research Service of the products named, nor criticism of similar ones not mentioned.

 7 1985 12 2 82 85 8 10 1985 American Peanut Research and Education Society 1985 American Peanut Research and Education Society Abstract

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.

 Key Words Budget analysis; , disease forecast models; , disease management; , epidemiology