There are over 100 varieties of Fusarium spp. with symptoms varying greatly according to host and pathogen species. Some symptoms commonly seen include yellowing of lower leaves, wilting, leaf chlorosis and vein clearing, stunted growth and red to brown discolouration of vascular tissue. Stem or cutting rot (but not always) appear as a soft, mushy rot at the base of a cutting or rooted plant, frequently with a purplish-reddish margin.
Sometimes bright red, globular fruiting bodies may form on stem bases in the case of advanced infection. Leaf spots often appear on immature leaves, are irregularly-shaped and tan-reddish brown in colour, sometimes surrounded by a chlorotic halo. Under wet conditions, creamy orange spore masses may be produced in lesions. Bulb rots often start at wounds or through cuts formed at harvest. The basal plate, scales and roots become brown-black, and the rot is generally dry and firm. Foliage turns yellow or brown and dies prematurely.
Many Fusarium spp. are host specific so check symptoms to the host to determine infection.