Fungicide Dip Treatments for Management ofBotrytis cinereaInfection on Strawberry Transplants

Abstract

Botrytis cinerea, the causal agent of Botrytis fruit rot, is annually introduced into Florida strawberry fields by infected transplants. The disease can be managed by fungicide sprays throughout the season; however, previous studies have demonstrated that several chemical classes are no longer effective owing to B. cinerea resistance. The objectives of this study were to evaluate the effectiveness of preplant fungicide-dip treatments of strawberry transplants on reducing B. cinerea colonization and to evaluate fungicide sensitivity of surviving B. cinerea isolates. Transplants of two strawberry cultivars, Winterstar ‘FL 05-107’ and ‘Florida Radiance’, were dipped in 11 different fungicides. After the plant establishment period, eight leaves per plot were collected before and 14 days after treatment to evaluate B. cinerea incidence. Isolates (n = 139) obtained from the transplants were tested for fungicide sensitivity. Plant diameter was measured 47 days after planting. All treatments, including the controls, reduced B. cinerea incidence by at least 77% compared with predip incidence. However, fungicide-resistant isolates were recovered from all treatments tested.