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SYMPTOMS OF FUNGAL DISEASES

If you suspect that a plant has a vascular wilt, then another symptom you can look for is VASCULAR DISCOLORATION or BROWNING. As a reaction to the infection, the xylem changes from its normal whitish color to a brown, green or gray color (see arrow). Not all vascular wilts lead to vascular discoloration, but when it does occur, vascular discoloration can be an important clue as to the cause of a wilt problem.

In this photo, vascular browning induced by the fungus Verticillium (cause of Verticillium wilt) is shown on one of this pathogen's major hosts, maple.