An economic analysis of preharvest fungicide applications to control Botrytis fruit rot in annual strawberries in Florida

The control of postharvest Botrytis fruit rot was evaluated during 1995-96, 1996-97, and 1997-98. Weekly applications of captan and thiram were examined at two or three different rates, respectively. Iprodione applications were combined with the captan and thiram treatments and applied alone for two peak bloom periods. Strawberry fruit were harvested and graded twice weekly for marketable yield and preharvest incidence of Botrytis fruit rot. For postharvest evaluations, fruit from four harvests were selected and stored at 4degreesC, and Botrytis fruit rot incidence was recorded over 14 days of storage. Fungicide treatments reduced the incidence of preharvest Botrytis fruit rot and increased marketable yield. Marketable yield data were then used to extrapolate production into net economic returns per hectare. In 1995-96, net returns per hectare ranged from a low of $16,008 in the control treatment to a high of $20,728 for captan. In 1996-97, net returns ranged from a low of $3,655 per hectare for the control to a high of $17,985 for captan + iprodione. In 1997-98, net returns varied from -$641 per hectare for iprodione to a high of $24,215 for captan.. Over the experiment's 3-year period, net returns averaged a low of $4,172 for iprodione alone to $19,074 for captan. The study concluded that, at roughly $1,000 per season, fungicide treatments represent a minor proportion of total costs, yet have large impacts on strawberry production profits.