Possible Causes of Disease Symptoms Resulting from the Feeding of Phytophagous Heteroptera
Symptoms of disease that develop on host plants under the influence of heteropterans have stimulated many entomologists to conduct investigations into the causes of deformation. In relation to plant-sucking insects, the following categories of phytotoxemias have been proposed by Carter (1962), based on external symptoms:
1. Local lesion at the insects feeding point, 2. Local lesions with development of secondary symptoms, 3. Tissue malformation, and 4. Symptoms indicating translocation of the causal entity.