Leaf scorch of strawberry - occurrence, harmfulness and control possibilities.

摘要

In the last years, leaf scorch caused by Diplocarpon earlianum has become a bigger problem on dessert strawberry plantations in Poland. The increase of the disease resulted from changes in planted strawberry cultivars and favourable weather conditions. The most susceptible cultivars were Kama and Kent. The symptoms were usually observed on oldest and well developed outer leaves as brown-reddish spots. The affected leaves turned yellow and died. Strong damage of leaves caused the decrease in yield and fruit quality. Good effectiveness in controlling the disease showed that Signum 33 WG, Pomarsol F 80 WG (thiram), Euparen Multi 50 WG (tolylfluanid) and Domark 100 EC (tetraconazole) were effective when used routinely on Polish strawberry plantations against grey mould or leaf spot. Laminarin (biological product) reduced the intensity of the disease by 65 and 38%, respectively, after 6 and 3 treatments.