Wilt, common symptom of plant disease resulting from water loss in leaves and stems. Affected parts lose their turgidity and droop. Specific wilt diseases—caused by a variety of fungi, bacteria, and viruses—are easily confused with root and crown rots, stem cankers, insect injuries, drought or excess water, soil compaction, and other noninfectious problems.

Bacterial Wilt
Bacterial wilt, caused by numerous species of the genera Corynebacterium, Erwinia, Pseudomonas, and Xanthomonas, induces stunting, wilting, and withering, starting usually with younger leaves. Stems, which often shrivel and wither, show discoloured water-conducting tissue. A bacterial ooze is often evident when infected stems are cut and squeezed. Rapidly expanding, dark green, water-soaked areas or streaks may develop first in leaves.
Bacterial wilt may be managed by growing resistant varieties; planting disease-free materials in well-drained, fertile soil that is clean or sterilized; observing stringent sanitation including weed- and insect-control measures; and rotating susceptible crops.