During 1985, a sudden decline was detected in sweet orange trees on Volkamer lemon rootstock in northwestern Venezuela. Symptoms in the affected plants were flaccid leaves, loss of brightness, defoliation, dry shoots, zinc deficiency symptoms in the new leaves, water sprouts on the trunk and in some cases death of the tree. These symptoms are very similar to those of blight in USA, declinio in Brazil and marchitamiento repentino in Uruguay. Preliminary results showed a relationship among the

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... ual symptoms of disease, the lack of water uptake by the trees and the presence of amorphous plugs in the trunk wood of affected plants. However, there were no differences in the zinc content of leaves, trunk wood and soil between healthy and diseased plants. Fusarium sp. and Colletotrichum sp. were isolated from root and shoot samples. Pathogenicity tests are underway to determine any relationship to the disease. No tristeza stem pitting or honey-combing were seen at the budunion of the trees. No plant parasitic nematodes were detected in the soil or roots of healthy and diseased plants.