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期 刊 ：植物保护学报 2011年

关键词：澳洲坚果；叶斑病；异色拟盘多毛孢；生物学特性；

Keywords:macadamia, leaf spot, Pestalotiopsis versicolor, biological characteristics,

摘 要 ：通过症状观察、致病性测定、形态和培养性状观察、rDNA-ITS序列分析及生物学活性测定将分离到的病原菌鉴定为异色拟盘多毛孢Pestalotiopsis versicolor (Speg.) Steyaert。菌株JG01在PDA培养基上菌落白色、背面呈橘黄色花瓣状,分生孢子盘墨汁状散生在菌丝上,分生孢子长梭形,大小为18.3~27.4 μm×5.6~7.7 μm,4隔,中间3个细胞着色,分隔处颜色很深,顶端附属丝一 般2~3根。ITS序列分析, 菌株JG01与P.versicolor(AF405298)亲缘关系最近,同源性达到99.60%。在PDMA培养基上,25~28 ℃、pH 4.0~6.0、碳氮源分别为葡萄糖和酵母提取物的条件下菌丝生长最快,培养条件对菌株产孢的影响不明显。

Abstract:In order to elucidate the causal agent of macadamia leaf spot and its taxonomic status, the causal bacterium was isolated and characterized with the pathogenicity test, morphology, culture feature observation, rDNA-ITS sequences assay and biological characteristics test. The results indicated that the causal agent belong to Pestalotiopsis versicolor. The colony of strain JG01 on PDA was white and orange ring in the rear, acervuli ink-like scattered on the mycelia, fibroblast-like conidia, 18.3-27.4μm×5.6-7.7μm, 4 septiferous 5 cells, the middle three cells colored, 2-3 top appendage, the rDNA-ITS sequence of strain JG01 shares 99.60% identity with that of P.versicolor (AF405298). Optimum conditions for mycelial growth was PDMA medial, 25-28℃, pH 4.0-6.0, D-glucose and yeast extraction. Effects of culture conditions on sporulation of strain are not obvious.

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