Tan-brown rot

Tan-brown rot, caused by the fungus Discohainesia oen (teleomorph Pezizella oenotherae), is a destructive fungal disease affecting strawberry crops. This pathogen is known for causing significant decay of both vegetative tissues and fruits, leading to heavy economic losses in commercial strawberry production.

The primary host for this fungus is the cultivated strawberry. The infection can manifest on leaves, petioles, and especially on ripening fruits. When the pathogen attacks the berries, it leads to rapid softening and browning, rendering the fruits unmarketable and susceptible to further colonization by opportunistic secondary microorganisms.

Symptoms are identified by the presence of tan or brown lesions on the surface of the affected berries. As the disease progresses, small, saucer-shaped, light-colored fruiting bodies called apothecia develop on the decayed tissue. These structures produce large amounts of conidia, which serve as the primary source of inoculum for further spread throughout the plantation.

The development and dissemination of the pathogen are highly dependent on environmental conditions, particularly high humidity, moderate temperatures, and prolonged wetness. Water-splashing from rain or irrigation systems facilitates the transfer of spores from the soil and infected debris to the healthy parts of the strawberry plants.

Effective management requires an integrated approach to disease control. Key strategies include:

• sanitation by removing and destroying all infected plant materials;
• maintaining proper plant spacing to improve canopy aeration;
• using mulch to create a physical barrier between the fruit and the soil;
• applying timely fungicide treatments during periods favorable for infection.