First, the symptoms The main damage to the leaves, the beginning of the orange red round spots on the leaves, after the expansion into a nearly round or irregular shape orange to dark brown necrotic spots, slightly concave, easy to break the perforation in the late, serious leaves full of disease Spots or multiple lesions merge, causing dry leaves. The pathogen is called Pseudomonas fluorescens Pseudomonas fluorescens biotype II bacteria, belonging to the genus Phytophthora in the bacteria kingdom. Pathogens and Pathogens The pathogens overwinter with diseased or infected seeds. When the conditions are appropriate, they invade from the leaf stomata, water holes, or wounds of the leaves and form a systemic infection. They are transmitted by the seeds of the bacteria and by rainwater, insects, and carriers. Expansion, high temperature and high humidity is favorable to the disease. The optimum temperature is 25-26°C and the highest is 38°C. The terrain is low, the soil viscosity is heavy, or the moisture retention is heavy. Second, control methods 1. 2 to 3 years of rotation with grass crops. Pre-sowing seeds are seeded with a spring weight of 0.3% of 47% Chunleiwang copper wettable powder. 3, to strengthen management, timely drainage after the rain, the protection of the area should pay special attention to ventilation and dampness, to prevent excessive humidity or long duration. 4. In the early stage of onset, spray 20% Thiobacillus copper suspension 600 times liquid or 47% Chunlei copper WP wettable powder 700 times, 20% Yeltzole 800 times. Imported Premium Coating Additive Coating auxilliaries, also known as paint accessories, the department of the preparation of coating auxiliary materials, can improve coating performance, promote the formation of coating film. There are many kinds, including drying agent, toughening agent, emulsifier, thickening agent, pigment dispersing agent, defoaming agent, levelling agent, anti-skidding agent, matting agent, light stabilizer, mildew proofing agent, antistatic agent (see plastic assistant), etc., among which the largest amount is drying agent and toughening agent. At present, the research of coating auxilaries, to be used for water emulsion paint auxilaries as the focus. Imported Premium Coating Additive,Imported Premium Thickening Agent,Imported Premium Wetting Agent,Imported Premium Antifoaming Agents Xingbang High Molecular Materials Co., Ltd. , https://www.chemicaladditive.com
2, the application of bio-organic fertilizer or compost organic compost.