For the long-term goal of improving planting success and reforestation of floodplain forests, an underbark inoculation test was performed using one-year-old seedlings from ten different half-sib lines of narrow-leaved ash (Fraxinus angustifolia) to examine the variability of host susceptibility to the ash dieback pathogen Hymenoscyphus fraxineus. Sizes of necrotic lesions, production of epicormic shoots and mortality was recorded in all inoculated seedlings 76 days after inoculation. Mortality of different half-sib lines ranged between 13.3% and 80%. Only one of the tested half-sib lines showed necrotic lesion sizes, production of epicormic sprouts and percentage of mortality substantially lower than all the other nine half-sib-lines of the respective symptom traits. About 20% of half-sib lines had reduced only one of these three symptoms. The other 70% of tested half-sib lines had large necrotic lesions, abundant occurrence of epicormic sprouts and high percentage of mortality. Mortality was also significantly influenced by seedling height at the time of inoculation with taller seedlings developing mortality more slowly than smaller seedlings. This study demonstrates significant differences in the susceptibility to H. fraxineus between different half-sib lines of F. angustifolia and the influence of seedling height on the development of ash dieback.

中文翻译：

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Hymenoscyphus fraxineus 在塞尔维亚白蜡不同半同胞系幼苗上的发育

为了提高洪泛区森林的种植成功率和重新造林的长期目标，使用来自十个不同半同胞窄叶灰 ( Fraxinus angustifolia ) 的一岁幼苗进行了树皮接种试验，以检查其变异性。宿主对灰枯萎病病原体Hymenoscyphus fraxineus 的易感性. 接种后 76 天，在所有接种的幼苗中记录坏死病灶的大小、表皮枝条的产生和死亡率。不同半同胞系的死亡率介于 13.3% 和 80% 之间。只有一个测试的半同胞系显示出坏死病灶大小、产生表皮芽和死亡率百分比显着低于各自症状特征的所有其他九个半同胞系。大约 20% 的半同胞系仅减轻了这三种症状中的一种。其他 70% 的测试半同胞系具有大的坏死病灶、大量出现的表皮芽和高死亡率百分比。死亡率也受到接种时苗高的显着影响，较高的苗与较小的苗相比，死亡率发展得更慢。H . fraxineus的不同半同胞线之间˚F。狭叶和苗高对灰枯萎病发育的影响。