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西北林学院经过3年多研究表明,土壤缺磷多钾是导致泡桐丛枝病发生的主因。在缺磷地区栽种泡桐,栽种前每株一般施1斤磷肥即可有效控制此病的发生。西北林学院1982年开始调查研究如何防治丛枝病,他们在河南、陕西、甘肃、四川等省的18个县,取样土80份,进行测定分析,发现磷含量高,发病率低;钾含量高,发病率高;
Northwest Forestry College after three years of research shows that soil phosphorus-deficient potassium is the leading cause of Paulownia witches broom disease. In the phosphorus-deficient areas planted Paulownia, plant per kilogram of general facilities before 1 kg of phosphate fertilizer can effectively control the occurrence of the disease. In 1982, Northwest Forestry College began to investigate how to prevent and cure the broom disease. In 18 counties of Henan, Shaanxi, Gansu and Sichuan provinces, 80 samples of soil samples were taken for analysis. The results showed that the phosphorus content was high and the incidence rate was low. High, high incidence;