This is Scientific American — 60-Second Science. I'm Christopher Intagliata.
When wildfires rip through a landscape, firefighters have the first — and most immediate — job. But then, that burned moonscape often passes into the hands of restoration ecologists, who yank out invasive species, and plant native seedlings in their place.
"We try to artificially give a start to these communities that should resemble the communities that were there prior to a disturbance." Matteo Garbelotto, a plant pathologist at U.C. Berkeley. The problem, he says, is that microscopic killers sometimes hitchhike on native seedlings grown in nurseries. As happened at one restoration site in the San Francisco Bay area, where restorers hoped that nursery-grown natives called toyons and sticky monkey flowers could be reintroduced.
"Plant ecologists were looking at them and thinking oh why are these toyons dying here, or why are these sticky monkey flowers dying in large numbers in this restoration site? And so it happens that each one of those plant species was reintroduced in a restoration effort and had one or sometimes multiple of these pathogens that belonged to the genus Phytophthora, which incidentally is the same genus of the pathogen that causes sudden oak death, and it's also the same genus of the pathogen that caused the Irish potato famine."
Garbelotto and his colleagues surveyed five native plant nurseries for the Phytophthora pathogen. And found that more than a quarter of the plants sampled were infected. They also discovered, in separate work, that a common chemical used to suppress the pathogen in nurseries can actually breed resistance. "The passage of these strains through these production facilities, sometimes it can make them more aggressive."
They reported their work in the journals PLOS ONE and Plant Pathology.
But there is a solution to root out these invisible killers. A yearlong regimen of stricter sanitation at native plant nurseries — like pasteurizing pots and soil — appeared to eliminate the pathogen. And disease-free seedlings means damaged landscapes have a better chance at bouncing back.
Thanks for listening for Scientific American — 60-Second Science. I'm Christopher Intagliata.
当森林大火肆虐时，消防员就有了他们首个也是最迫切的任务 。但之后，那些被烧毁的如月球表面的景观通常会交给修复生态学家，他们要剔除入侵物种，然后在原地种植本地幼苗 。
“我们试图人为启动这些植物群的建立，让其与火灾前的样子相似 。”加州大学伯克利分校的植物病理学家马特奥·加贝罗托说到 。他表示，问题是那些微型杀手有时会在苗圃中生长的本地幼苗身上搭便车 。就像旧金山湾区恢复点发生的情况一样，修复人员原本希望能重新引入苗圃培育的“柳叶石楠”和“粘猴面花”这两种本地植物 。
加贝罗托和同事调查了5个本地植物苗圃来研究疫霉属病原体 。他们发现，超过四分之一的植物样本被感染 。在另一项独立研究中，他们还发现一种用来抑制苗圃病原体的常见化学物质确实能导致耐药性 。“当这些菌株穿过这些生产设施时，有时会使病原体更具侵略性 。”
但有一种方法可以根除这些隐形杀手 。在本地植物苗圃实行长达一年的严格卫生制度，比如对盆栽和土壤进行巴氏杀菌，似乎可以消除病原体 。无病害幼苗意味着受损自然环境恢复原貌的几率更大 。
谢谢大家收听科学美国人——60秒科学 。我是克里斯托弗·因塔利亚塔 。
1. prior to 在…之前；先于；
It is important to enrich the soil prior to planting.
2. belong to 属于（某个类别、类型或群体）；
Lions and tigers be long to the cat family.
3. root out 铲除；清除；
The generals have to root out traitors.
4. bounce back 恢复；复原；重整旗鼓；
We lost two or three early games in the World Cup, but we bounced back.