ruskotautit

Ruskotautit is a term used in Finnish plant pathology to describe a group of diseases that cause russeting or brown, corky patches on plant tissues, most commonly on fruit skins and leaves. The term does not denote a single pathogen; rather, it refers to several fungal and fungal-like pathogens whose activity leads to surface browning and textural changes. The concept is used in Finnish agricultural extension materials and among farmers and plant pathologists in Finland and surrounding Nordic countries.

Symptoms typically include coppery to brown patches on fruit skins, leaves with corky, roughened areas, and sometimes widespread russeting on stems. Severity ranges from cosmetic blemishes to lesions that reduce photosynthesis or fruit quality.

Causes are diverse, often involving environmental conditions that promote infection such as high humidity and leaf wetness, and susceptible host species that include various fruit crops and ornamentals. Because ruskotautit encompass multiple diseases, accurate diagnosis requires laboratory confirmation, including microscopy, culture, or molecular methods.

Management focuses on cultural practices to reduce leaf wetness and inoculum, the use of resistant or less susceptible cultivars when available, proper pruning and sanitation, and appropriately timed fungicide programs following local extension guidance. Regional occurrence is greatest in humid temperate climates, with Finland being a primary reference region for the term.

See also: russeting, plant pathology, crop protection.