Postharvest dipping of kiwifruit in iprodione to control stem-end rot caused by botrytis cinerea

Abstract

Kiwifruit (Actinidia deliciosa (A. Chev.) C.F.Liang et A.R.Ferguson) cv. Hay ward from four orchards were treated with the dicarboximide fungicide, iprodione, applied as a preharvest spray or a postharvest dip to control stem-end rot caused by Botrytis cinerea (Persoon: Fries). Differences in the incidence of stem-end rot existed between orchards but in each orchard only low levels of infection were found. The incidence of stem-end rot was lower in the fungicide dipped fruit than in fruit from the control or preharvest sprayed treatments. The proportion of dicarboximide resistance in B. cinerea isolates from fruit rots was highest in the fruit that were dipped. There were no consistent differences between orchards in the proportions of dicarboximide resistance. Iprodione residue levels were higher on the dipped than on the sprayed fruit. © 1994 The Royal Society of New Zealand.