一、分布这是一种世界性的传染病害,从1929年以来,有五大洲27个国家先后报道了本病在本国的危害,其中澳大利亚,新西兰、美国、南非等国家报道的材料较多,对病害的症状、病原菌、侵染机制、发病规律及防治措施都做了许多研究工作。该病能引起松树枯芽、枯叶、枯梢,还能引起根茎腐烂,边材兰变,严重时大面积松林枯死。近年来我国也流行了这种病害,受害很重,现已开始注意观察研究,由于本病是人工林的大害,所以应值得注意。 First, the distribution This is a worldwide infectious disease, since 1929, 27 countries on five continents have reported the disease in the country’s harm, including Australia, New Zealand, the United States, South Africa and other countries reported more material, The disease symptoms, pathogens, infection mechanisms, incidence and prevention and control measures have done a lot of research work. The disease can cause pine shoots, dead leaves, dead shoots, but also cause root rot, sapwood blue, severe pine forests withered large area dead. In recent years, the disease has also been prevalent in our country. The victims are very heavy. Now we have begun to pay attention to observational studies. Since this disease is a major detriment of plantations, it should be noted.