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近年山东省有上万亩油松、黑松、赤松因发生烂皮病被毁,直接经济指失达千万元。根据调查,松烂皮病严重发生与以下几方面因素有关。
In recent years, there are 10,000 mu of Chinese pine, black pine and red pine in Shandong Province. According to the survey, a serious occurrence of loose stubble with the following factors.