Strawberry Leaf Scorch


Leaf scorch is caused by the fungus Diplocarpon earliana. Symptoms of leaf scorch consist of numerous small, irregular, purplish spots or “blotches” that develop on the upper surface of leaves. The centers of the blotches become brownish. Blotches may coalesce until they nearly cover the leaflet, which then appears purplish to reddish to brown.

The fungus overwinters on infected leaves. The fungus produces spore forming structures in the spring on both surfaces of dead leaves. These structures produce spores abundantly in midsummer. In the presence of free water, these spores can germinate and infect the plant within 24 hours. Older and middle-aged leaves are infected more easily than young ones.


Scorched strawberry leaves are caused by a fungal infection which affects the foliage of strawberry plantings. The fungus responsible is called Diplocarpon earliana. Strawberries with leaf scorch may first show signs of issue with the development of small purplish blemishes that occur on the topside of leaves. Over time, the spots will continue to grow larger and darken. In severe cases, dark spots may even cover entire portions of strawberry plant leaves and cause them to completely dry and fall from the plant. Though the foliage of the infected plants is not aesthetically pleasing, it is seldom that the presence of this fungus impacts the quality of the strawberry crop itself.

Management

While leaf scorch on strawberry plants can be frustrating, there are some strategies which home gardeners may employ to help prevent its spread in the garden. The primary means of strawberry leaf scorch control should always be prevention. Since this fungal pathogen over winters on the fallen leaves of infect plants, proper garden sanitation is key. This includes the removal of infected garden debris from the strawberry patch, as well as the frequent establishment of new strawberry transplants. The creation of new plantings and strawberry patches is key to maintaining a consistent strawberry harvest, as older plants are more likely to show signs of severe infection. When making new plantings, always ensure that good planting practices are implemented. These practices include the use of proper plant spacing to provide adequate air circulation, and the use of drip irrigation. The avoidance of waterlogged soil and frequent garden cleanup will help to reduce the likelihood of spread of this fungus.




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