Fungicide management strategies for control of strawberry fruit rot diseases in Louisiana and Mississippi

Abstract

Sixteen fungicide treatments were evaluated for control of strawberry fruit diseases in five fungicide studies conducted at Hammond, LA and Poplarville, MS during the 2002, 2003 and 2005 fruiting seasons. The most frequent fruit rots at harvest were anthracnose fruit rot caused by Colletotrichum acutatum, stem-end rot caused by Gnomonia comari, and Botrytis fruit rot caused by Botrytis cinerea. Fungicides from seven groups were shown to be effective for control of strawberry fruit rot diseases in these trials, and the commercial combination fungicides were often the most effective. In at least two trials when compared to the untreated control, total fruit rot was less on berries from the pyraclostrobin+boscalid, cyprodinil+fludioxonil, azoxystrobin, fenhexamid+captan, and captan treatments; anthracnose fruit rot was less on berries from the cyprodinil+fludioxonil and azoxystrobin treatments; and stem-end rot was less on berries from the cyprodinil+fludioxonil, pyraclostrobin+boscalid, captan, azoxystrobin, and pyraclostrobin treatments. While low in all trials, a significant reduction in Botrytis fruit rot incidence occurred in four trials. Berries from the cyprodinil+fludioxonil, fenhexamid, fenhexamid+captan, pyraclostrobin+boscalid, captan, pyrimethanil, and azoxystrobin treatments had the lowest incidence of Botrytis fruit rot. Efficacious fungicides from various FRAC groups will provide strawberry growers with more options for controlling diseases while managing fungicide resistance.