Diagnosis
Bacterial Wilt of Tomato
wilting of young leaves The initial symptoms of the disease on tomato are wilting of the youngest leaves with slight yellowing of older leaves.
As the disease progresses, the wilting causes the plant leaves to dry and wither.
browning of vascular tissue To diagnose the disease, pull plants suspected of having the disease out of the ground and look for browning of the water-conducting vascular system which is directly under the outer tissue. This browning is easy to see on the lower stem and is characteristic of the bacterial invasion. Often times in severe cases, the browning of the vascular system will extend far up into the stem of the plant.
wilting plant When the disease has progressed, the amount of wilting and internal discoloration will be greater. Susceptible plants wilt, become dry looking and often die very quickly.
healthy and infected stems Because vascular browning can be caused by other pathogens, another method, an ooze test, can be used to confirm the diagnosis. Cut a piece of lower stem. Place in clear containers with water. Stand undisturbed for few minutes. Whitish streams of bacteria mass will ooze out from diseased tissues (right stem), while no stream can be observed from healthy tissues (left stem).
 

 
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