Disease - Pierce's Disease
Causal Organism - Xylella fastidiosa
Symptoms & Damages - In this disease, the symptoms of burning like dryness are seen on the green leaves of grapes. The scorched areas develop more in the center of the leaves and later turn brown. Eventually the leaves fall.
Stunted growth of bunches with leaves symptoms. Diseased stems mature irregularly.
Diseased plants have late spring growth in the coming season.
Initial leaves of the plant are found bent & dwarf. The leaves and fruits show earlier symptoms in later seasons.
Disease control - It is very difficult to control this disease in grapes on a commercial scale.
The base of the infected plant should be given drench treatment i.e. treatment of grape vines once or twice a week with 4 liters of 50 to 100% tetracycline solution and copper oxychloride, cupric hydrotoxide should be sprayed.
Spraying of Benomyl 50% should be done at an interval of 10 to 14 days.
Disease Management - Only disease resistant varieties should be sown.