Symptoms first appear as interveinal chlorosis, or yellowing of the younger terminal leaves.Applying fertilizer-grade manganese sulfate at 20 to 40 gm per vine, or 100 to 200 kg per acre, depending on vine size and severity of the deficiency.

Foliar application of Mn can be sprayed for immediate effect mix manganese sulfate at the rate of 160 gram plus 80 gram of hydrate lime per 200 litres of water.  Two application usually will provide season-long control of manganese symptoms.  First appln.just after bloom or when symptoms first appear and second two weeks later.