沈阳市城区油松枝枯病病情及分析

采用随机抽样和定点观察的方法对沈阳城区油松发生枯枝病的病情进行调查,并对病害发生规律进行分析。结果显示:该病害在沈阳城区发生普遍,其平均发病率为47.23%,病情指数为14.88。病害发生与立地条件及林分因子关系紧密。阳坡发病轻,平均发病率为79.38%,病情指数为31.41;20～30年生油松发病重,平均发病率为80.02%,病情指数为40.94;林分密度越高,发病越重,林分密度>750株.hm-2的样地的平均发病率为93.04%,病情指数为47.22;树高15m以上的油松发病重,平均发病率为97.28%,病情指数为46.21;油松和红松混交林发病最重,发病率为100%,病情指数为68.59。

Analysis on the Occurrence and of Pinus tobulaeformis Die-back in Shenyang

The occurrence of Pinus tobulaeformis die-back in Shenyang was investigated by random sampling and on-the-spot field observation,and the occurrence regularity was also analyzed.The results showed that the disease was common in Shenyang.The average disease rate and index were 47.23% and 14.88 respectively.The occurrence of the disease was correlated with forest site and stand factors.Adretto is light,in which the average rate of disease occurrence and index were 79.38% and 31.41 respectively.P.tabulaeformis with ages of 20 to 30 years old took a serious disease,in which the average disease rate and index were 80.02% and 40.94,respectively.The higher of stand density,the disease was more serious.In the sampling areas,in which the stand density was over 750 plants per hm2,the average disease rate and index were 93.04% and 47.22,respectively,Trees with a height of over 15 meters took a serious disease,the average disease rate and index were 97.28% and 46.21,respectively.In the mixed forests of P.tabulaeformis and Korean pine,the disease was more serious,the average incidence and index were 100% and 68.59,respectively.