Blight
Blight is a rapid and complete chlorosis, browning, then death of plant tissues such as leaves, branches, twigs, or floral organs. Accordingly, many diseases that primarily exhibit this symptom are called blights. Several notable examples are:
Typhula blight
Typhula blight (commonly called gray snow mold or speckled snow mold) is most commonly known as a turf disease, but can also be a problem with wheat. Typhula blight is caused by a "Typhula" fungus, either "Typhula incarnata" or "T. ishikariensis". "Typhula incarnata" is the causal agent for gray snow mold and "T. ishikariensis" causes speckled snow mold. Snow molds are caused by cold tolerant fungi that require snow cover or prolonged periods of cold, wet conditions. Typhula blight is most notably found in the turf industry, affecting a wide range of turfgrasses. Upon the snow melt, gray circular patches of mycelium are found. These mycelia produce a survival structure called a sclerotia that survives the warm summer months. Typhula blight is commonly controlled with fungicide applications in the late fall and by other cultural practices. If unchecked, snow molds can cause severe turf loss.