【作者】 范永强；

【导师】 栾雨时；

【作者基本信息】 大连理工大学 ， 作物遗传育种， 2008， 硕士

【摘要】 本研究分别从土壤和杜鹃花根部分离了丛枝菌根真菌(AMF)和杜鹃类菌根真菌(EMF)。通过接种草莓和越橘两种小浆果植物宿主,分别筛选到了一株极易人工培养的丛枝菌根真菌和5株杜鹃类菌根真菌。利用简单的形态学观察和分子生物学手段,对分离的菌根真菌做了初步的鉴定分析。并且,通过接种草莓宿主,对分离得到的丛枝菌根真菌的促生作用进行了研究。本研究从土壤里分离出一株易人工培养的丛枝菌根真菌,经形态学和ITS序列分析鉴定为Penicillium pinophilum,并基于其ITS序列构建了系统发育树。使用该菌在‘章姬’草莓上做了接种实验研究其促生作用。实验中,比较了两种类型接种物—土根类型接种物和鲜菌丝类型接种物的作用效果,同时以未接种的植株作为空白对照。接种60天后,检测了草莓植株的光合作用及菌根侵染率。对于每个处理,分别在接种60,80,100天后调查了其根、茎、叶以及全株的鲜重、干重和氮、磷、钾的含量情况。结果表明,丛枝菌根(AM)的形成明显改善了草莓的生长及光合作用,促进了宿主植物对氮、磷元素的吸收,但对于钾元素的吸收影响不大。同时,由于鲜菌丝接种物的侵染率更高,故其作用效果要好于土根类型接种物。这是在中国首次报道了接种P.pinophilum在草莓上形成丛枝菌根,并且由此明显改善了宿主植物的生理特性。另一方面,本研究从映山红和金达莱两个多年野生杜鹃花品种中分离得到了25株内生真菌。用它们侵染“北丰”和“北蓝”两个越橘品种。一个月后,经显微观察发现有5株内生真菌能够在宿主植物根表皮细胞内形成典型的杜鹃类菌根结构。采用形态学观察和ITS序列分析的方法对此5株真菌经进行了的鉴定,并构建了系统发育树。通过“十字格线交叉法”测定了这5株杜鹃类菌根真菌的侵染率为3.8%-51.3%不等。更多还原

【Abstract】 Arbuscular mycorrhizal fungi (AMF) from the soil and ericoid mycorrhizal fungi (EMF) from Rhododendron were isolated in the study. One species of easily-cultured species AMF and five species of EMF were screened by inoculating two types of berries, strawberry and blueberry, respectively. The isolated funus were identified with the morphology and molecular biology methods. Futhermore, the effect of the AMF on the nutrient uptake and photosynthesis of strawberry was tested.One easily cultured new strain of AMF was isolated from the soil, which was identified as Penicillium pinophilum with the morphology and molecular biology methods, and a polygenetic tree was constructed based on its ITS sequences. A synthesis experiment was conducted with the isolated fungus and the strawberry Fragaria x ananassa Duch. CV. ’Zoji’. Two types of inocula, soil-root and fresh-hyphae types, were compared to uninoculated controls. The rate of arbuscular mycorrhiza (AM) photosynthesis activities and colonization were determined 60 days post inoculation. The fresh and dry weights, and phosphorus, nitrogen and potassium contents of the roots, stems, leaves and whole plants were measured 60, 80, 100 days post inoculation, respectively. The results showed that AM colonization improved the growth and photosynthesis characters of strawberry, and enhanced uptake of phosphorus and nitrogen, with little effect on the potassium. As fresh-hyphae inoculum resulted in higher inoculation rates than the root-soil inoculum, better results were received when the previous one was used as the inoculum. This was the first time to use P. pinophilum strain to synthesize mycorrhiza within the strawberry in China, and the physiology of the host plant was improved by the AM formation.On the other hand, twenty-five strains of root endophytic fungus were isolated from the Rhododendron simsii and R. dauricum L., which were used to inoculate two blueberry cultivars , ’Bluecrop’ and ’Northblue’. One month post inoculatin, five strains were obseved to form the ericoid mycorrhize within the root epidermal cells of host plants. The EMF were identified by morphological characterizations and the ITS sequence analysis, and a polygenetic tree was constructed based on their ITS sequences. The infection frequencies of the host epidermal cells were calculated to range from 3.8% to 51.3% by the grid-line intersect method.更多还原