Submitted to: Crop Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/28/2010
Publication Date: 9/28/2010
Citation: Peres, N., Seijo, T., Turechek, W. 2010. Pre- and post-inoculation activity of protectant and systemic fungicides for control of anthracnose fruit rot of strawberry under different wetness durations. Crop Protection. 1105-1110. Interpretive Summary: Anthracnose is one of the most important fungal diseases in commercial strawberry production. Growers rely on fungicides to control this disease to produce marketable fruit. We looked at the efficacy of pre- and post-infection-period applications of the protectant fungicide Captan and the systemic fungicide Switch on the development of anthracnose fruit rot in field studies in Maryland and Florida. Our study indicated that for short wetting events, such as those associated with seasonal thunderstorms, growers can apply Captan up to 8 hours after the wetting event and achieve control similar to that of a protective spray. For longer wetting events, Switch provides superior post-infection activity. Over the course of a season this approach would likely lead to fewer, better timed fungicide applications and may delay the onset of resistance to certian classes of fugicides. The results reported in this paper will be useful to growers interested in controlling anthracnose.
Technical Abstract: A protectant fungicide (Captan) and a systemic fungicide (Switch – fludioxonil + cyprodinil) were evaluated as pre- and post-inoculation applications for control of anthracnose fruit rot (AFR), caused by Colletotrichum acutatum, under a short (6 or 8 h) or long (18 or 24 h) wetting period. Evaluations were conducted for two seasons in Maryland and for two seasons in Florida. Both Captan and Switch were highly effective for control of AFR when applied prior to inoculation, but control was more effective under the shorter wetting period. Switch was as effective when applied 4, 8, or 24 h post inoculation as when applied before inoculation, but control was better under the short wetting period. Captan was effective when applied 4 or 8 h after inoculation under the short wetting period, but was ineffective at 24 h post-inoculation and at any time under the long wetting period. The post-infection activity of Switch allows greater flexibility for managing AFR when fungicide applications are scheduled based on weather-based decision-support systems.