Corky Root Rot
Characteristic banding pattern of corky root rot (left) and roots with severe case of corky root rot (right). Note the cracked, corky bark-like roots.
Verticillium Wilt
Characteristic v-shaped necrosis and yellowing of leaves (left) and vascular discoloration of tomato plants consistent with Fusarium wilt or Verticillium wilt (middle; right).
Fusarium Wilt
Tomato plant with Fusarium wilt (left). Note the yellow discoloration on one half of the plant (right).
Root Knot Nematode
Tomato roots with severe root knot nematode galling (left; middle; right).
Black Dot Root Rot
Roots with sclerotia of Colletotrichum coccodes, the causal agent of black dot root rot. The honey-brown discoloration is also characteristic of this disease (left; middle; right).