blight

Blight is a term used to describe rapid deterioration and destruction affecting living organisms or environments. In plant pathology, blight refers to diseases that produce sudden, extensive damage to foliage, stems, or fruit, often caused by fungal or oomycete pathogens. The term is also used in urban and social contexts to describe areas of severe decay and neglect.

Plant blights are typically characterized by rapid lesion development, wilting, and browning of infected tissues. Many blights are caused by water molds (oomycetes) such as Phytophthora and by fungi such as Alternaria. A well-known example is potato late blight (Phytophthora infestans), which infects potato and tomato leaves and tubers and can spread quickly in cool, wet conditions.

No matter the organism, management emphasizes prevention and containment: use resistant cultivars when available; rotate crops and remove infected plant material; improve air circulation and reduce humidity; and apply appropriate fungicides or bactericides as recommended locally by agricultural authorities.

Urban blight describes declining urban districts marked by vacancy, abandoned buildings, crime, and shrinking tax bases. Contributing factors include deindustrialization, population loss, and insufficient investment in housing and services. Responses typically involve redevelopment, housing rehabilitation, improved policing, and incentive programs intended to attract investment and residents, though outcomes vary and some approaches raise concerns about displacement and equity.