1. Symptoms of Damage: The primary damage occurs on the leaves, followed by effects on fruits and shoots. Initially, the leaves show water-soaked, light brown spots surrounded by a yellow-green halo. Over time, these spots expand into nearly round reddish-brown lesions. In some cases, multiple lesions merge to form larger patches. If the humidity in the greenhouse is high, yellow, sticky bacterial exudate may appear on the back of the infected leaves. Eventually, the lesions dry out, and cracks form along the edges. As the damaged tissue falls off, holes (perforations) are left in the leaves. These perforations often have irregular, ragged edges, and sometimes necrotic tissue remains around the hole. When the infection is severe, the affected leaves drop prematurely. On the fruit, the disease starts as small, water-soaked, brownish spots that gradually turn dark purple and become slightly sunken as the lesion expands. High humidity can cause yellow, sticky bacterial ooze to emerge from the infected areas. Later, the lesions dry and crack, and if the cracks are deep, the fruit may rot or become unmarketable. New shoots can develop two types of lesions. The first is the spring ulcer spot, which appears on branches that grew during the previous summer (infected the year before). As the new leaves begin to grow, small, round, dark brown sores form and gradually enlarge into oval-shaped lesions. The affected area becomes sunken, and the bark cracks. Severe infections can lead to dieback of the new shoots. The second type is the summer ulcer spot, which appears at the end of summer on the current year’s shoots, resulting in water-soaked, dark purple spots that do not spread much and dry up quickly. 2. Prevention of Perforation: (1) Apply organic fertilizers to strengthen the tree's health and improve its resistance to disease. Especially in heavy soils, adding manure or other organic materials can help improve soil structure and drainage. (2) Before heating the greenhouse, perform proper pruning to ensure good air circulation and light penetration. Remove all dry branches, diseased leaves, and fallen fruits, and burn or bury them deeply to eliminate overwintering bacterial sources. (3) After the greenhouse is warmed, strictly control temperature—especially during flowering—and manage irrigation carefully to avoid excess moisture. Ensure timely ventilation. After removing the plastic cover, pay attention to drainage during the rainy season to prevent waterlogging. (4) For chemical control, before the temperature rises in the greenhouse, spray with 5° Brix lime sulfur. If the perforation was severe the previous year, after the peach leaves have fully expanded, apply 45% Dendron at 800 times dilution, or 72% streptomycin at 2500 times, or 3500 times for streptomycin or neomycin, or 50% thiram at 500 times, or 65% zincosate at 500 times, or 70% mancozeb at 500 times. Typically, spray every 10 to 15 days for 3 to 4 applications. Additionally, a zinc sulfate lime solution (1:4:240 ratio of zinc sulfate:slaked lime:water) has shown good results in controlling bacterial perforation. However, it may cause phytotoxicity, so a small test should be conducted before full application. Sour And Spicy Flavored Kimchi Sour And Spicy Flavored Kimchi,Spicy Cabbage,Spicy Cabbage Korean,Sour And Spicy Sauce Kimchi Yanbian Jingangshan Food Co., Ltd , https://www.ybjgsfood.com