Inability of the lone star tick, Amblyomma Americanum (L.), to resist desiccation and maintain water balance following application of the entomopathogenic fungus Metarhizium anisopliae var. anisopliae (Deuteromycota)
Inability of the lone star tick, Amblyomma Americanum (L.), to resist desiccation and maintain water balance following application of the entomopathogenic fungus Metarhizium anisopliae var. anisopliae (Deuteromycota)
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孤星蜱 Amblyomma Americanum (L.) 在施用昆虫病原真菌 Metarhizium anisopliae var. 后无法抵抗干燥并维持水平衡。
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发表时间：
2006
期刊：
影响因子：
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通讯作者：
Justin L. Tank
中科院分区：
文献类型：
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作者：
J. Yoder;J. Ark;J. Benoit;Eric J. Rellinger;Justin L. Tank
摘要我们报道了用昆虫病原真菌金龟子绿僵菌处理雌性孤星星蜱（Amblyomma americanum）时，其透水性发生迅速变化。失水量几乎是未暴露于这种真菌的对照蜱的两倍。因此，在大于0.85a v-0.93av（a v = % RH/100）的临界平衡活性（CEA）的水合气氛下，防止蜱稳定身体水分水平（水分增加/水分损失），并在更短的时间内达到其脱水耐受极限。因此，水平衡的破坏是真菌感染的致病后果。这作为评价自然界中常见的土壤霉菌（野生蜱分离株）、尼日尔、枝孢霉、光滑青霉和短帚霉对蜱的影响的基准。与M.绿僵菌处理，局部应用绿僵菌对蜱水平衡无影响。Cladosporioides处理后，蜱的失水率下降，而S. brevicaulis介于两个极端之间。失水率表明光滑拟单胞菌可能是蜱类病原体，而光滑拟单胞菌可能是蜱类病原体。尼日尔显然不能利用蜱虫作为底物。这些常见霉菌引起的干燥增强表明当地真菌区系作为蜱虫种群的天然调节剂的重要性。失水率也提供了一种工具，以评估不同的真菌菌株的致病性，在生物防治蜱的应用目标。
Abstract We report that female lone star ticks (Amblyomma americanum) experience a rapid change in water permeability when treated with the entomopathogenic fungus Metarhizium anisopliae. The amount of water loss is nearly double the rate of control ticks not exposed to this fungus. As a result, ticks are prevented from stabilizing body water levels (water gain ≠ water loss) at hydrating atmospheres greater than the critical equilibrium activity (CEA) of 0.85a v-0.93av (a v = % RH/100) and reach their dehydration tolerance limit in less time. Thus, disruption of water balance is a pathogenic consequence of fungus infection. This served as a benchmark for evaluating effects on ticks of frequently encountered soil molds in nature (wild tick isolates), Aspergillus niger, Cladosporium cladosporioides, Penicillium glabrum and Scopulariopsis brevicaulis. In contrast to M. anisopliae treatment, no effect on tick water balance was noted with topical application of C. cladosporioides, but water loss rates of ticks following treatment with S. brevicaulis fell between both extremes. Water loss rates imply that P. glabrum may be a tick pathogen, whereas A. niger is apparently not able to use ticks as a substrate. Enhanced desiccation arising from these common molds shows the importance of local mycoflora as natural regulators of tick populations. Water loss rates also provide a tool to assess the pathogenicity of different fungal strains targeted for application in the biological control of ticks.