CHEMICAL CONTROL OF BACTERIAL BLIGHT OF WALNUT
The disease intensity was measured by counting spots on leaf samples collected in July, by recording external damage to fruits on July and September, and damage to seeds after the fruits were harvested and dried. Dimensions of dried fruits were also taken. Treatments were compared using the pathometric variables incidence and severity.
On all treatments, no correlation was found between levels of external damage to fruits and of damaged seed tissues. Significant differences in dried fruit volume were observed among treatments. Copper compounds, especially Kocide, were the most effective, although none of the treatments could provide an adequate control of the disease.
Differences among treatments apparently result from their action on the process of infection, the development of the disease after penetration of the pathogen being unchecked in all instances.
A simple key for recording disease intensity on fruits is proposed and discussed.