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作 者 ：郑武;冯明光

期 刊 ：应用生态学报 2007年 18卷 07期 页码：1573-1577

摘 要 ：

在15 ℃～35 ℃的温度范围内比较测定了玫烟色拟青霉(Paecilomyces fumosoroseus) 6株野生菌的菌落生长、产孢量及孢子活力.结果显示，3个指标均以25 ℃左右最好，但同一温度下菌株间或同一菌株在不同温度下的差异显著， 菌株Pfr116和Pfr6206具有相对稳定优良的生长、产孢及活孢率性状.对不同浓度多菌灵对6株野生菌的菌落生长和单孢菌落形成的影响测定表明，菌株间存在较大差异.不同多菌灵浓度对单孢菌落形成的抑制率观察值可用逻辑斯蒂模型较好地拟合(r²≥0.90).用所获参数估计的最低禁菌浓度MIC值显示，Pfr4205和Pfr116对多菌灵表现为低抗性（MIC≤20.0 μg·ml^-1）；Pfr153、Pfr612和Pfr2175属于低水平中抗，MIC值仅略大于20 μg·ml^-1；而Pfr6206的MIC值高达93.5 μg·ml^-1，接近MIC>100 μg·ml^-1的高抗标准.因此，Pfr6206为适温性和抗多菌灵特性俱佳的菌株，可作为抗多菌灵和适应不同季节或地区的害虫生防菌剂的候选菌株.

Abstract:A total of six wild strains of fungal biocontrol agent Paecilomyces fumosoroseus were grown at 15 ℃-35 ℃ to reveal their variations in colony growth, conidiation, and conidial viability. The results showed that the test three indices were the best at 25 ℃, but differed significantly at different temperatures for a given strain or at a given temperature among test strains. The strains Pfr116 and Pfr6206 behaved better or more stably than other strains at 15 ℃-35 ℃. The sensitivities of the fungal strains to gradient concentrations of fungicide carbendazim were assayed at the optimal temperature, based on their colony growth diameters and the counts of colony forming units (CFU). The inhibitory effect of carbendazim concentration on CFU counts fitted well to a Logistic model, with high coefficients of determination being achieved for all the strains (r²≥0.90). The fitted minimal inhibitory concentration (MIC) values showed a low carbendazim resistance of strains Pfr4205 and Pfr116 (MIC≤20.0 μg·ml^-1), whereas the other four strains fell within medium resistance to the fungicide (20≤MIC≤100). The MIC of strain Pfr6206 (93.5 μg·ml^-1) was very close to the high resistance level of MIC>100 μg·ml^-1. Therefore, strain Pfr6206 was satisfactory with both the temperature fitness and the carbendazim resistance, and could be considered as a candidate strain for a fungal formulation adapting to more variable crop systems against insect pests.

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