BSP - Black Speck (Pepper Spot)
Type: Physiological Disorder
Black Speck, also known as Pepper Spot, is a physiological disorder that affects cabbage, especially Chinese Napa Cabbage in the United States and Europe. The disease affects the outer leaves of the cabbage, but often can seen deep in the center of the head. Individual brown and black spots develops on the wrapper leaves, and then spread to the inner leaves. Dark lesions spots appear on the cabbage ribs. It appears as if black pepper was sprinkled on the midrib section of the leaves, hence the name "pepper spot". The cause is unknown, but high rates of fertilizers and fluctuations of temperatures have been reported to increase the susceptibility. Symptoms occur in the fields during growth and during cold storage. The best option is to use disease resistant varieties.