äppelsskabb

Apple scab is a common fungal disease that affects apple trees, caused by the pathogen Venturia inaequalis. It is prevalent in regions with cool, moist climates, as these conditions favor the spread of the fungus. The disease primarily manifests on the leaves and fruit of apple trees, though it can also impact twigs and blossoms.

Symptoms of apple scab typically appear on the leaves in the spring as small, olive-green spots. As the infection progresses, these spots enlarge and darken, often becoming velvety in appearance. Severely infected leaves may turn yellow and drop prematurely, weakening the tree. On the fruit, scab lesions begin as small, dark, irregular spots that can enlarge and develop a rough, corky texture. In severe cases, the fruit can become misshapen and unmarketable.

The fungus overwinters on fallen leaves and infected twigs. In the spring, spores are released and spread by wind and rain to infect new growth. Repeated infections throughout the growing season can lead to significant crop loss and reduced tree vigor. Management strategies include planting resistant apple varieties, practicing good sanitation by removing fallen leaves and infected debris, and applying fungicides at critical times during the growing season. Pruning to improve air circulation within the tree canopy can also help reduce disease pressure.