VOA慢速英语2019 狗狗能嗅到影响柑橘树的作物病害（在线收听）

New research suggests that dogs might be able to help save diseased citrus trees.

新的研究表明，狗狗可能是拯救患病柑橘树的好帮手。 

A group of scientists trained dogs to use their sense of smell to detect a crop disease called citrus greening.The disease has affected orange, lemon and grapefruit trees in the American states of Florida, California and Texas.

一群科学家训练狗狗利用它们的嗅觉来检测一种叫做柑橘绿病的农作物疾病。这种疾病已经影响到了美国佛罗里达州、加利福尼亚州和德克萨斯州的橘子树、柠檬树和葡萄柚树。

The dogs can detect the disease weeks to years before it appears on tree leaves and roots, the researchers report.A study on their findings was published recently in the Proceedings of the National Academy of Sciences.

研究人员报告称，在这种病害出现在树叶和树根部数周甚至数年之前，狗狗就可以探测到它。他们的研究结果最近发表在《美国国家科学院院刊》上。

The report says using dogs is also faster, less costly and more exact than having people collect hundreds of leaves for lab analysis.

报告说，这种方法比让人们收集数百片树叶拿到实验室分析更快、更便宜、更准确。 

Timothy Gottwald is a researcher with the U.S.Department of Agriculture and a co-writer of the study.He told The Associated Press,"This technology is thousands of years old – the dogs nose.Weve just trained dogs to hunt new prey:the bacteria that causes a very damaging crop disease."

蒂莫西·格特伍德是美国农业部的一名研究员，也是这项研究的作者之一。他告诉美联社，“这项技术已经有上千年历史了，那就是狗的鼻子。我们只是训练狗去捕捉新的猎物:一种会导致严重农作物病害的细菌。”

Citrus greening is caused by a bacteria that is spread by a tiny insect that feeds on the leaves and stems of citrus trees.Once a tree is infected,there is no cure.

柑橘变绿是由一种微小昆虫传播的细菌引起的，这种昆虫以柑橘树的叶子和茎为食。一旦树被感染，就没有治愈的方法。

The disease has also hurt citrus crops in Central and South America and Asia.

这种疾病还影响到了中美洲、南美洲和亚洲的柑橘类作物。 

In one experiment involving grapefruit trees in Texas,trained dogs were correct 95 percent of the time in telling the difference between newly infected trees and healthy ones.

在德克萨斯州进行的一项关于柚子树的实验中，训练有素的狗狗在分辨新感染的树和健康的树之间的区别时，正确率高达95%。

" The earlier you detect a disease,the better chance you have at stopping an epidemic"by removing infected trees, Gottwald said.

“你越早发现疾病，你就越有可能通过清除受感染的树木来阻止一场流行病。” 

Matteo Garbelotto studies plants at the University of California, Berkeley.He says the new research shows that dogs can detect an infection well before current methods.Garbelotto has been involved in similar research but had no part in the new study.

马特奥·加贝罗托是加州大学伯克利分校植物研究学者。他说，新的研究表明，狗狗可以在当前的检测手段得出结果以前就检测到这种病菌。加贝罗托也参与了类似的研究，但没有参与到该项新研究中。

Laura Sims is a plant scientist with Louisiana Tech University.She praised the steps taken to find out if the dogs were detecting the bacteria itself or a plants reaction to an infection.

劳拉·西姆斯是路易斯安那理工大学的植物科学家。她对为证明狗狗是否可以检测该种病菌以及检测植物对感染的反应所采取的步骤表示赞同。

To do that,the researchers infected different kinds of unrelated plants with the bacteria in a laboratory.The dogs were still able to pick out the infected plants.

为了做到这一点，研究人员在实验室里用细菌感染了不同种类的无关植物。这些狗仍然能够分辨出受感染的植物。

Gottwald said, " Youve seen dogs working in airports, detecting drugs and explosives.Maybe soon you will see them working on more farms."

格特伍德说:“你见过在机场工作，在探测毒品和炸药的狗狗。也许很快你就会看到他们更多的在农场工作。”