Local adaptation of a parasite to solar radiation impacts disease transmission potential, spore yield, and host fecundity*
Local adaptation of a parasite to solar radiation impacts disease transmission potential, spore yield, and host fecundity*
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寄生虫对太阳辐射的局部适应会影响疾病传播潜力、孢子产量和宿主繁殖力*
DOI：
10.1111/evo.13940
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发表时间：
2020
期刊：
影响因子：
3.3
通讯作者：
Duffy, Meghan A.
中科院分区：
文献类型：
--
作者：
Rogalski, Mary Alta;Duffy, Meghan A.
环境传播的寄生虫在非生物环境中度过一段时间，在那里它们受到各种应激源的影响。如果我们想要了解宿主-寄生虫的相互作用如何在环境梯度上发生变化，了解它们如何面对这一挑战是至关重要的。我们使用了浮游动物-细菌宿主-寄生虫系统，其中阳光的可用性(太阳辐射)影响疾病动态，以寻找寄生虫对阳光暴露的局部适应的证据。我们还研究了寄生虫菌株之间对阳光耐受性的差异如何影响宿主的繁殖。从更清澈的湖泊(阳光穿透力更强)收集的寄生虫菌株对阳光暴露的负面影响最耐受，这表明当地对阳光条件的适应。这种适应对寄生虫既有代价，也有好处：来自更清澈湖泊的寄生虫菌株产生的传播阶段(孢子)相对较少，但这些菌株更具感染力。在试验性的阳光暴露后，最耐受阳光的寄生虫菌株对寄主繁殖力的影响与从未暴露在阳光下的孢子一样少。世界各地湖泊的阳光可获得性差异很大。我们的结果表明，日光照射对寄生虫施加的选择性压力可能会影响寄生虫和宿主的适合度，潜在地推动疾病流行和宿主种群动态在阳光可用性梯度上的变化。
Environmentally transmitted parasites spend time in the abiotic environment, where they are subjected to a variety of stressors. Learning how they face this challenge is essential if we are to understand how host–parasite interactions may vary across environmental gradients. We used a zooplankton–bacteria host–parasite system where availability of sunlight (solar radiation) influences disease dynamics to look for evidence of parasite local adaptation to sunlight exposure. We also examined how variation in sunlight tolerance among parasite strains impacted host reproduction. Parasite strains collected from clearer lakes (with greater sunlight penetration) were most tolerant of the negative impacts of sunlight exposure, suggesting local adaptation to sunlight conditions. This adaptation came with both a cost and a benefit for parasites: parasite strains from clearer lakes produced relatively fewer transmission stages (spores) but these strains were more infective. After experimental sunlight exposure, the most sunlight-tolerant parasite strains reduced host fecundity just as much as spores that were never exposed to sunlight. Sunlight availability varies greatly among lakes around the world. Our results suggest that the selective pressure sunlight exposure exerts on parasites may impact both parasite and host fitness, potentially driving variation in disease epidemics and host population dynamics across sunlight availability gradients.