Uncinula necator

Grape powdery mildew

Symptoms

Whitish powdery patches on the affected plant parts. All the above ground plant parts are susceptible to infection. Powdery growth on both the surface of the leaves. Affected leaves becomes malformed and discoloured. The powdery pustules subsequently become grey and finally dark coloured. Shredding of flowers and poor fruit set due to floral infections. Early infected berries become malformed, cracking of skin of berries, shred and rarely ripe. No fruit formation if the infection occurs early.

Disease cycle

Powdery growth of the fungus consists of mycelium, conidiophores and conidia. Dormant mycelium and conidia in infected shoots and buds spread through air from plant to plant. Warm temperature with enough humidity and cloudy weather are favourable conditions for the pathogen severity.

Management

Sanitation and proper pruning after shedding of leaves.

Spray Veni GoKlean at the rate 1.25 to 1.5 ml per litre of water at 12-15 days intervals as preventative spray and or after recognition of the disease symptoms.