Regular disease surveys have highlighted the changing status of cotton diseases over time and

provided valuable insights into the factors affecting their distribution and severity.

Verticillium wilt of cotton is caused by a fungus (Verticillium dahliae) that infects the host plant via the roots and colonises the vascular system.

A disease can only occur when a virulent pathogen contacts a susceptible host under favourable environmental conditions. The incidence and severity of a disease reflects the occurence of these three factors.