【作者】 姜自如；

【导师】 曹支敏；

【作者基本信息】 西北农林科技大学 ， 森林保护学， 2011， 硕士

【摘要】 杨树溃疡病是杨树重要枝干病害,世界上报道的树木溃疡病病原菌有10余种。在我国,引起杨树溃疡病的真菌以茶藨子葡萄座腔菌(Botryosphaeria ribis Grossenb. et Duggar)和污黒腐皮壳菌(Valsa sordida Nit.)为常见。为深入了解陕西省杨树溃疡病病原真菌地理分布和寄主抗病性,笔者对陕西省不同地区的杨树溃疡病进行了调查,并对不同种群病原菌进行了初步研究,得出的结果如下:(1)对陕西省不同地区杨树溃疡病病原菌进行调查、分离鉴定结果显示杨树溃疡病的症状主要有三种表现:水泡型、圆斑型和烂皮型。杨树溃疡病菌包括聚生小穴壳(Dothiorella gregaria Sacc.)、金黄壳囊孢(Cytospora chrysosperma Fr.)、杨细盾霉(Coniothyrium populinum Schulz. et Sacc.)和镰刀菌(Fusarium sp.)四种病原真菌。四种病原真菌在关中平原均有分布,并以D. gregaria为优势种;陕北地区杨树溃疡病主要由Coniothyrium populinum及Cytospora chrysosperma Fr.所致;陕南地区杨树溃疡病发生少。(2)培养性状表明,不同种溃疡病菌、同一种群不同菌系间菌落生长速度存在差异。D. gregaria菌落的平均生长速度最快。接种试验表明D. gregaria致病性最强,C. populinum致病性最弱。聚生小穴壳(D. gregaria Sacc.)和杨细盾霉(C. populinum Schulz. et Sacc.)在陕西省存在着培养性状与致病性分化。同时,除Coniothyrium populinum外,D. gregaria、C. chrysosperma及Fusarium sp.三个种群中同一菌系的菌落生长速度与其致病力之间呈显著相关性。(3)调查结果显示同一地区不同杨树品种之间抗病性呈显著性差异,关中地区杨树溃疡病抗病性大小顺序为:中林美荷杨>84K杨>107杨>毛白杨。同一品种在不同地区杨树溃疡病感病指数也呈显著性差异。毛白杨溃疡病总体上在关中地区发病较重,在铜川以北地区较轻。84K杨在宝鸡眉县发病情况较轻,而在铜川耀州发病较严重。杨树溃疡病的病情指数与杨树胸径(树龄)及其所处的立地条件之间呈不显著相关性,而与杨树品种及其所处生态地理之间有显著相关性或呈极显著相关性。(4)对所有供试的13个菌系D. gregaria进行ITS-rDNA-PCR扩增,结果产生单一带谱,约300bp,具有高度保守性。证明了基于培养性状和形态特征对种的分类是基本正确的。更多还原

【Abstract】 Poplar canker is an important branch diseases of poplar, which has been reported more than 10 species of pathogenic bacteria in the world.? In China, poplar canker is caused frequently by Botryosphaeria ribis Grossenb. et Duggar and Valsa sordida Nit.. In order to better understand the geographical distribution of pathogenic and host resistance in Shaanxi province, the author investigated poplar canker in different regions of Shaanxi province, and did a preliminary study on different species of pathogen.The main conclusions are as following:(1) The study on the investigation and isolation of poplar canker’pathogen in different regions of Shaanxi Province showed that poplar canker had three main symptoms: blisters type, circinal spot type and bark rot type, including Dothiorella gregaria Sacc., Coniothyrium populinum Schulz. et Sacc., Cytospora chrysosperma Fr. and a few Fusarium sp.. Four kinds of poplar canker’pathogen were widely distributed in the middle of Shaanxi, and D. gregaria was the dominant species; poplar canker was mainly caused by Coniothyrium populinum Schulz. et Sacc. and Cytospora chrysosperma Fr. in northern Shaanxi; and few poplar canker was caused by D. gregaria Sacc. in southern Shaanxi.(2) Cultural characteristics showed that different kinds of poplar canker’pathogens or different strains of the same group of colony growth vary was different, of which the fastest was D. gregaria. Inoculating tests proved that D. gregaria showed more intense pathogenicity, C. populinum showed weaker pathogenicity, and both of them showed differentiation of culture character and pathogenic in Shaanxi province. Furthermore, D. gregaria, C. chrysosperma and Fusarium sp. showed significantly correlation between its growth rate and its pathogenic at the 0.05 level in the same strains, while C. populinum was not.(3) The survey data showed that the resistance varied significantly in different poplar species at the 0.05 level in the same area, the order of resistance in middle Shaanxi was: Populus deltoides×P. nigra > Populus alba×P. glandulosa > Populus×euramericana cv.‘74/76’> Populus tomentosa, and the disease index of the same species varied significantly at the 0.05 level among different regions. The disease index of Populus tomentosa in middle Shaanxi was more serious than that in the north from Tongchuan. The disease index of Populus alba×Populus glandulosa was less serious in Mei County of Baoji than in Yaozhou of Tongchuan. There was not significant correlation between poplar canker disease index and poplar diameter (age of the trees) or the site conditions, however, there was significant correlation between poplar canker disease index and the poplar species or ecogeography at the 0.05 level.(4) The ITS-rDNA-PCR amplification of the 13 D. gregaria tested strains produced a single band spectrum, about 300bp, which was highly conservative, and thus proved the classification of species which based on colonial and anamorph morphological characters was almost correct.更多还原