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湿地松(Pinus elliottii)幼林中松针褐斑病菌(Lecanosticta acicola)分生孢子借雨水溅落而释放和传播。当风速在1m/s左右的情况下,分生孢子从一株1.7m高的病树上被雨水溅散,约有80％降落在病树周围3.4m范围内,最远不超过8.5m,即树高的5倍。病害在林分中最初常形成发病中心,自1982年11月至1985年4月,固定观察一个标准地,发现病害自中心病株向外扩展的平均距离为8m,感病株率增长50％,感病指数增长23。病害在湿地松林中终年都有发展,以4月下旬至6月下旬发展最快,9至10月次之,这些时候的旬平均气温大约是20～25℃,旬降雨量也是一年中最多和较多的。
Conidiospores of Lecanosticta acicola in young Pinus elliottii forest splashed by rain and released. When the wind speed is about 1m / s, the conidia splashed from a 1.7m high diseased tree and about 80% landed within 3.4m around the diseased tree, the furthest no more than 8.5m, That is 5 times the height of the tree. The disease often first formed the center of disease in the forest. From November 1982 to April 1985, a standard observation was observed fixedly. The average distance from the central diseased plant was 8m and the susceptible plant rate increased by 50% , The index of illness increased 23. The disease develops throughout the year in the wetland pine forest and develops fastest from late April to late June, followed by September to October. The average temperature at these times is about 20-25 ℃, and the maximum rainfall in one year And more.