Scab

Scab Common name Scab Causal agent Scab is a fungal disease caused by several fungi from the genus Fusicladium and venturia. They form crustaceous spots on the leaves, stems, and fruits. Scientific name Venturia spp. Spilocaea oleaginea Fusicladium Symptoms & Signs The infection starts as pale yellow spots on the leaves, which eventually turn into dark, olive-green spots and spread to stems and fruits. The fungal growth is usually visible on the underside of the foliage. Infected leaves twist, wilt, and fall off prematurely. Similarly, the infected stems show flower drops. The fruits display black spots with red margins, which may transform into sunken lesions with spores on their margins. Severely infected fruits crack and drop early. Transmission As a fungal disease, it spreads through spores that travel by means of air, water, insects, or contact with infected tools. Cool, wet weather conditions favor the spread of this disease. Time of concern Spring Common hosts Apples Olives Loquat Pear Willow Potatoes Peaches