Fusarium is a genus of common soilborne fungi. Most live as saprophytes on decaying plant matter while a few are also important plant pathogens.

While there are many different pathogenic Fusarium species, some of the most damaging diseases are caused by strains of one species complex, Fusarium oxysporum. They cause vascular wilt diseases by entering the roots and colonising the water-conducting tissue (xylem). This causes older leaves to yellow and plants eventually wilt and die.

For more information read this practical fact sheet on fusarium wilt diseases, factors that favour fusarium diseases, and management strategies.