Strawberry Diseases: Part One

Everyone knows that strawberries are one of the most popular fruits. Fortunately, they are also easily grown in your backyard, to provide your family with sweet delicious fruits. However, there are also a number of diseases that can affect strawberries, so it is important to educate yourself about them in order to ensure that your strawberries remain healthy and sound throughout the growing season.

Botrytis Fruit Rot

This disease, also known as gray mold, typically appears as a greyish film on the fruit of the strawberry. Although often the disease causes the fruit to become mushy, in areas with less humidity it also results in in the fruit becoming dry and leathery. Prevention is crucial to this disease, and often involves removing dead leaves and other detritus from the field, as the disease is spread easily. Other preventative measures including regularly treating your plants with fungicide, to ensure that the fungus does not have a chance to grow and ultimately cause the disease.

Mucor Fruit Rot

This strawberry disease, like other varieties of rot, can enter the fruit through even the tiniest wound, so it is important to ensure that your plants remain as solid and unspoiled as possible. It usually manifests itself as a coat of tough, wiry mycelium and spheroidal spore-bearing structures. Keeping your field sanitary is an essential part of preventing infection, so be sure to remove the entire fruit from the stem, as any remainders can serve as a site of future infection. You should also focus on cultivars with thicker skins, as these are better able to resist fungal infections.

Rhizopus Fruit Rot

Rhizopus fruit rot manifests as water-soaked, discolored spots on the fruit, and these will rapidly grow, often leaving the fruit itself brown and leaky. The spores of this fungal disease are airborne, and it can often survive colder periods (it lasts throughout the year in California). However, it does not survive at temperatures below 42 degrees, so cooling of fruit after harvest is an excellent means of control. Like other types of rot, field sanitation is important, and cultivars with harder flesh are often more resistant.

Strawberry Leaf Blotch

This strawberry disease typically occurs in the early parts of the season, particularly after heavy periods of rain. You can identify the disease by the presence of tan or grey lesions on the leaves of the plant, which can sometimes cover up to half of the surface. Fortunately, strawberry plants usually grow out of the disease after the rains stop.

Sources

University of California Statewide Integrated Pest Management Program