chlorosis: this disease will lead to the chlorosis of part of the stems and leaves or the whole leaves, which will lead to yellowing. Therefore, cultivation management can be strengthened, which can solve this problem. Leaf spot: it mainly harms the leaf parts. At first, it is light brown small spots, and later it forms irregular large spots. Sooty blotch: It mainly attacks leaves and branches, and it is covered with black pulverized coal. Scab anthracnose: this disease will harm leaves, veins, petioles and fruit stalks.