Introduction to the symptoms of grape black pox

It is a fungal disease, which mainly harms the green tender parts of grapes, such as young fruits, leaves, petioles, pedicels, shoots and so on. Black pox disease can occur from sprouting to late growth. Severe infestation of young fruits in spring and summer appears dark brown halo at first, like "bird's eye". Most of the disease spots can be connected into large spots, and the disease spots are hardened or cracked in the later stage, and the disease spots are limited to the pericarp but not deep into the pulp. Leaves infected with different density of brown spots, the center of the initial spot gray-white, after the perforation showed a star-shaped crack, the periphery with purple-brown halo. New shoots, branches, petioles or tendrils are infected, showing irregular short brown spots at first, then grayish black, edges dark brown or purple, central depression cracking, and in severe cases, tender shoots stop growing, curl or atrophy and die.