新疆天山中部河谷林杨树黑斑病发生动态及影响因子

Occurrence Dynamics and Influencing Factors of Black Spot Disease on Poplar Trees in the Valley Forest of the Central Tianshan Mountains in Xinjiang

为掌握新疆天山中部河谷林地区杨树黑斑病的发生动态以及相关影响因子,明确新疆河谷林杨树黑斑病病原菌种类,对天山中部河谷林地区进行调查。以中高海拔河谷林和低海拔河谷林的有林地(郁闭度>0.3)为研究对象,采用踏察法与样带法调查杨树黑斑病周年发生消长规律,环境温度、湿度、海拔、方位等因素对杨树黑斑病的影响。并采用科赫法则确定杨树黑斑病病原菌类别。结果表明,病原菌于每年的6月下旬至7月上旬开始侵害,直至8月下旬至9月中旬为发病高峰期;海拔、温湿度对病害发生有显著影响(P<0.01)。杨树黑斑病在日均相对湿度60%~70%和日平均温度14~18℃时有明显的上升波动。新疆天山中部河谷林杨树黑斑病的病原菌为杨生褐盘二孢菌(Marssonina brunnea)。

In order to get the occurrence dynamics and related influencing factors of poplar black spot disease in the Tianshan River Valley forest in Xinjiang and to clarify the pathogenic bacteria species of the disease on trees here,an investigation was conducted.The forested land in the middle-high altitude valley forest and low-altitude valley forest(canopy density>0.3)was taken as the research object,and the observation and transect method was used to investigate the effects of annual growth and decline law of poplar black spot disease and other factors such as environmental temperature,humidity,altitude,orientation on poplar black spot disease incidence.In addition,Koch’s law was used to determine the pathogenic of poplar black spot disease.The results showed that the pathogenic invaded the host from late June to early July every year,and the peak period of incidence was from late August to mid-September.Altitude,temperature and humidity had a significant impact on the occurrence of the disease(P<0.01).Poplar black spot disease showed obvious rising fluctuations when the daily average relative humidity was between 60%and 70%and the daily average temperature was between 14℃and 18℃,which resulted in the fact that the pathogen causing black spot disease on poplar trees in the valley forests in Xinjiang was Marssonina brunnea.