树木枝干溃疡病菌致病力分化研究

应用人工接种的方法,对不同地理区域、不同寄主上的24个Botryosphaeria dothidea菌株、6个B.berengeriana菌株在不同抗性杨树上接种后的致病力分化进行了研究.结果显示:接种后是否形成愈伤组织是树木抗性的表现,也是真菌致病力大小的表现;B.dothidea菌株存在致病力分化现象,表现为强、中、弱3种类型,中等致病力的菌株是优势类群;以杨树为接种材料,24个B.dothidea菌株的致病力呈现一定的地理分化现象,致病力从强到弱依次为:华东(华南)>西北>华北(华中)>东北,即菌株致病力从我国南方向北方有逐渐变小的趋势;苹果轮纹病菌和干腐病菌的致病力也呈现出南方菌株大于北方菌株的特点.从溃疡病菌株的致病力出发分析了5种杨树的抗病性,其结果与以往的观察结果相一致.

Pathogenicity differentiation of tree stem canker pathogenic fungi

The pathogenicity differentiation of 24 Botryosphaeria dothidea strains and 6 B.berengeriana strains coming from different regions and host plants was studied after inoculation.The results showed that the forming of callus was the reflection of not only tree resistance,but also the pathogeni-city of fungi.There was the appearance of pathogenicity differentiation of B.dothidea strains and based on the degree of pathogencity the strains were divided into 3 groups,the middle group was dominant.The B.doyhidea strains showed the appearance of geographical differentiation according to their host plants locations.Strains from East(or South-east) China had the highest pathogenicity,strains from NorthEast China had the lowest pathogenicty and strains from North-west and North(central of China) were the middle.So was the pathogenicity of apple stem canker and ring-rot isolates.The resistance of 5 poplar trees was consistent with the results of the previous studies.