经济学人137:烟草提取物可用于植物病虫害

 　　Science and technology

　　科学和技术

　　Pesticides¹

　　农药

　　Smoking them out

　　把它们熏死

　　Tobacco extracts protect plants from pests and pathogens

　　烟草提取物可用于植物病虫害

　　THERE are, as Paracelsus put it, no poisons—only poisonous doses.

　　巴拉赛尔士曾说：世上其实没有毒药，所谓的毒性只是剂量变化引起的而已。

　　That is certainly true of nicotine².

　　对于尼古丁，这当然是确切无疑的。

　　The amount in a puff³ from a cigarette acts as a pleasant stimulus⁴.

　　吸一口烟你可能会觉得神清气爽，

　　The amount in a packet of 20, injected in one go, would kill you.

　　但是如果一次性注射一包20支烟的尼古丁剂量，可是会要了你的命的。

　　The Victorians understood this and regularly used nicotine as a lethal⁵ poison—not for people except in the minds of a few crime novelists but for insects.

　　维多利亚时代的人明白这一点，并且已经把尼古丁作为一种常见的致命毒药来使用—不是用来杀人除了在一些犯罪小说家的构思中，而是用来杀虫。

　　The invention of modern, synthetic⁶ insecticides has more or less killed that practice off.

　　而现代合成杀虫剂的发明在一定程度上结束了尼古丁的使命。

　　But Cedric Briens of the University of Western Ontario is thinking of reviving it, and is also asking whether tobacco has any other pesticidal⁷ properties that might be exploited by the hard-pressed horticulturalist.

　　现在，西安大略大学的塞德里克?布里安则又在考虑重新启用尼古丁，同时在设法验证烟草是否还有其他杀虫功能，期望可为饱受病虫害之苦的园艺家所利用。

　　To find out, Dr Briens and his colleagues at Canada's agriculture ministry⁸ ground up dried tobacco leaves using a blender and a sieve⁹.

　　为此，布里安博士和他在加拿大农业部的同事们用搅拌机和筛子将烟叶碾碎，

　　They then heated the result in a pressurised, oxygen-free environment to distil¹⁰ out what they could in the form of a treacly oil.

　　然后将碾碎后的烟叶在高压、无氧环境下加热，提取出一种以粘稠油状存在的物质。

　　They tested this oil on 11 species of fungus¹¹ and four types of bacterium¹² that are common agricultural problems.

　　他们用这种油对农业中常见的11种真菌和4种杆菌，

　　They also tried it on the larvae¹³ of Colorado beetles¹⁵, a notorious pest of potatoes.

　　以及一种常见的令人闻之生厌的马铃薯害虫—科罗拉多甲虫进行了试验。

　　As they report in Industrial and Engineering Chemistry Research,

　　他们的研究结果发表在《工业化学与工程化学研究》上。

　　the researchers found that several pestilential organisms were affected¹⁶ by the oil.

　　研究报告显示这种油对好几种有害的有机生物有作用。

　　Specifically they discovered that Pythium ultimum, a fungus that attacks aubergines, peppers, lettuces¹⁷, tomatoes and cucumbers as seedlings¹⁸,

　　研究明确地发现，在这种油的作用下，危害幼苗期茄子、青椒、莴苣、番茄、黄瓜的真菌，

　　Clavibacter michiganensis, a bacterium that kills young plants and deforms¹⁹ fruits, and Streptomyces scabies,

　　腐霉病菌，可使幼苗致死、果实畸形的杆菌—马铃薯环腐病菌，以及另一种导致马铃薯烂痂病，

　　a second bacterium, which causes potatoes to develop revolting scabs and for which no treatment currently exists, all stopped growing in the presence of the oil.

　　且目前没有有效防治方法的杆菌—疥链霉菌，均被抑制生长。

　　The beetle¹⁴ larvae, too, were killed—though that was no surprise, since the oil contained a lot of nicotine.

　　此外，甲虫幼虫也可被杀死—这其实是意料之中的，因为这种油里含有大量的尼古丁。

　　What was a surprise was that removing this nicotine did not diminish the oil's effectiveness against bacteria and fungi²⁰, and made it only marginally less effective against beetle larvae.

　　但意料之外的是，将这种油去除后，对细菌和真菌的影响作用却并没有降低，只是对甲虫幼虫的作用在一定程度上减轻了。

　　The crude oil killed all of the larvae whereas the nicotine-free stuff left a fifth of them alive after two days.

　　布满这种油的环境中，所有的甲虫幼虫都被杀死，散乱分布的情况下，两天后也只有五分之一存活。

　　Clearly, there are other pesticides at work, and finding what they are is the next task.

　　显然，其它具有杀虫作用的物质在起作用，下一步任务就是找出这些物质。

　　Meanwhile tobacco has proved itself a more useful substance than even the Victorians realised. Can its rehabilitation²¹ be far off?

　　这些发现证明了烟草不止可以用来做香烟，它甚至具有比维多利亚时代的发现更大的作用。如此，烟草的这种“复兴”还会远吗？

1 pesticides   

n.杀虫剂( pesticide的名词复数 )；除害药物

参考例句：

• vegetables grown without the use of pesticides 未用杀虫剂种植的蔬菜
• There is a lot of concern over the amount of herbicides and pesticides used in farming. 人们对农业上灭草剂和杀虫剂的用量非常担忧。 来自《简明英汉词典》

2 nicotine   

n.(化)尼古丁，烟碱

参考例句：

• Many smokers who are chemically addicted to nicotine cannot cut down easily.许多有尼古丁瘾的抽烟人不容易把烟戒掉。
• Many smokers who are chemically addicted to nicotine cannot cut down easily.许多有尼古丁瘾的抽烟人不容易把烟戒掉。

3 puff   

n.一口(气)；一阵(风)；v.喷气，喘气

参考例句：

• He took a puff at his cigarette.他吸了一口香烟。
• They tried their best to puff the book they published.他们尽力吹捧他们出版的书。

4 stimulus   

n.刺激，刺激物，促进因素，引起兴奋的事物

参考例句：

• Regard each failure as a stimulus to further efforts.把每次失利看成对进一步努力的激励。
• Light is a stimulus to growth in plants.光是促进植物生长的一个因素。

5 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

6 synthetic   

adj.合成的，人工的；综合的；n.人工制品

参考例句：

• We felt the salesman's synthetic friendliness.我们感觉到那位销售员的虚情假意。
• It's a synthetic diamond.这是人造钻石。

7 pesticidal   

adj.杀虫的

参考例句：

• Patent technology, Pesticidal, Sterilization Antipruritic, Deodorization, Hair protecting and rehabilitation. 修复损伤皮毛等多种功效。 来自互联网
• The pesticidal effect on aphid of the anaerobic fermentation liquid is studied by field experiment. 利用蚜虫作为试验对象，通过田间试验的方法，对厌氧发酵液的杀虫效果和杀虫机理进行了研究。 来自互联网

8 ministry   

n.(政府的)部；牧师

参考例句：

• They sent a deputation to the ministry to complain.他们派了一个代表团到部里投诉。
• We probed the Air Ministry statements.我们调查了空军部的记录。

9 sieve   

n.筛，滤器，漏勺

参考例句：

• We often shake flour through a sieve.我们经常用筛子筛面粉。
• Finally,it is like drawing water with a sieve.到头来，竹篮打水一场空。

10 distil   

vt.蒸馏；提取…的精华，精选出

参考例句：

• You can distil fresh water from the sea.你可以用蒸馏法从海水中提取淡水。
• The writer managed to distil his ideas into one succinct article.作家努力把他的想法浓缩成一篇简练的文章。

11 fungus   

n.真菌，真菌类植物

参考例句：

• Mushrooms are a type of fungus.蘑菇是一种真菌。
• This fungus can just be detected by the unaided eye.这种真菌只用肉眼就能检查出。

12 bacterium   

n.(pl.)bacteria 细菌

参考例句：

• The bacterium possibly goes in the human body by the mouth.细菌可能通过口进入人体。
• A bacterium is identified as the cause for his duodenal ulcer.一种细菌被断定为造成他十二指肠溃疡的根源。

13 larvae   

n.幼虫

参考例句：

• Larvae are parasitic on sheep.幼虫寄生在绵羊的身上。
• The larvae prey upon small aphids.这种幼虫以小蚜虫为食。

14 beetle   

n.甲虫，近视眼的人

参考例句：

• A firefly is a type of beetle.萤火虫是一种甲虫。
• He saw a shiny green beetle on a leaf.我看见树叶上有一只闪闪发光的绿色甲虫。

15 beetles   

n.甲虫( beetle的名词复数 )

参考例句：

• Beetles bury pellets of dung and lay their eggs within them. 甲壳虫把粪粒埋起来，然后在里面产卵。 来自《简明英汉词典》
• This kind of beetles have hard shell. 这类甲虫有坚硬的外壳。 来自《现代汉英综合大词典》

16 affected   

adj.不自然的，假装的

参考例句：

• She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
• His manners are affected.他的态度不自然。

17 lettuces   

n.莴苣，生菜（ lettuce的名词复数 ）；生菜叶

参考例句：

• My lettuces have gone to seed. 我种的莴苣已结子。 来自《现代汉英综合大词典》
• Are these lettuces home-grown or did you buy them in the market? 这些生菜是自家种的呢，还是你在市场上买的？ 来自辞典例句

18 seedlings   

n.刚出芽的幼苗( seedling的名词复数 )

参考例句：

• Ninety-five per cent of the new seedlings have survived. 新栽的树苗95%都已成活。 来自《现代汉英综合大词典》
• In such wet weather we must prevent the seedlings from rotting. 这样的阴雨天要防止烂秧。 来自《现代汉英综合大词典》

19 deforms   

使变形，使残废，丑化( deform的第三人称单数 )

参考例句：

• Bad rheumatoid arthritis deforms limbs. 严重的类风湿性关节炎会造成四肢变形。
• The specimen deforms under a tensile stress applied parallel to the fibres. 试样在平行于纤维的张应力作用下发生变形。

20 fungi   

n.真菌，霉菌

参考例句：

• Students practice to apply the study of genetics to multicellular plants and fungi.学生们练习把基因学应用到多细胞植物和真菌中。
• The lawn was covered with fungi.草地上到处都是蘑菇。

21 rehabilitation   

n.康复，悔过自新，修复，复兴，复职，复位

参考例句：

• He's booked himself into a rehabilitation clinic.他自己联系了一家康复诊所。
• No one can really make me rehabilitation of injuries.已经没有人可以真正令我的伤康复了。