经济学人下载:根瘤蚜虫(2)

If correct, says Francois Delmotte, who works at INRAE's campus in Bordeaux
Francois Delmotte在INRAE位于波尔多的营地工作，也是该项目的领导之一，

and is one of the project's leaders, the finding fits with certain historical facts.
他表示，如果是这样，那么该发现和某些历史事实相吻合。

Though the Mississippi valley was annexed from France by Britain and Spain in the mid-18th century, and passed eventually to the United States,
虽然，在18世纪中期，英国和西班牙从法国那里吞并了密西西比河谷，并最终转让给了美国，

many French settlers remained in the area and France retained trading links, particularly with New Orleans, for a long time.
但很多法国移民仍留在这个地区，法国在很长一段时间内保持着贸易联系，尤其是与新奥尔良的贸易。

Dr Delmotte says it would not be surprising if, in the 19th-century age of steamships and naturalists,
Delmotte博士表示，如果是在19世纪蒸汽船和自然法学派时代，河岸葡萄被保存在凉爽干燥的容器中，

phylloxera survived on cuttings of V. riparia stored in a cool, dry hold to be brought to a botanical garden in France.
然后被带到法国的植物园中，根瘤蚜虫能够在这些河岸葡萄的切口处存活下来，这并不奇怪。

Or, even more ironically, that it was imported with vines destined to cure their French cousins of an earlier imported blight—powdery mildew.
更具讽刺的是，它是与葡萄藤一起进口的，这些葡萄藤是要用来治疗它们法国表亲的白粉病。

The genetic diversity of European phylloxera is limited compared with that of its North American counterpart, says Dr Rispe.
和北美同类相比，欧洲根瘤蚜虫基因的多样性是有限的，Rispe博士说到。

That points to there having been only one or two introductions, with subsequent diffusion of the pest by people and their agricultural machines.
这表明，这种害虫只被引入一次或两次，随后由于人类和他们的农业机械而扩散开来。

However, another of the paper's authors, Astrid Forneck of the University of Natural Resources and Life Sciences in Vienna,
但该论文的另一位作者，维也纳自然资源和生命科学大学的Astrid Forneck表示，

says it remains a possibility that a separate introduction infested eastern Europe,
仍有可能是另一次引入让这种害虫在东欧大量滋生，

perhaps via the Austro-Hungarian empire's experimental vineyards at Klosterneuburg.
或许是通过奥匈帝国在克洛斯特新堡的试验性葡萄园。

In America phylloxera attacks wild vines' leaves. It stimulates them to create galls in which it can live and feed,
在美国，根瘤蚜虫袭击葡萄藤的叶子。它刺激叶子产生虫瘿，以便它们生存和进食，

but which, from the plant's point of view, serve to isolate the problem. When it attacks cultivated vines, though, it goes for the roots.
但从植物的角度来看，这有助于区分看待这个问题。虽然当它攻击种植葡萄藤时，它会攻击根部。

These root galls open a plant to infection by bacteria and fungi, leading to its death.
这些根部的虫瘿让植物遭受细菌和真菌的感染，导致它的死亡。

For a long time, researchers hunted for a single molecule, produced by the insect, that stimulated the growth of galls.
很长一段时间以来，研究人员都在寻找昆虫产生的一种刺激虫瘿增长的单分子。

Blocking the action of this, they hoped, would phylloxera-proof all vines. But here the sequencing project produced a disappointment.
他们希望，阻止这一行为可以防止所有的葡萄藤出现根瘤蚜虫。但基因排序项目的结果令人失望。

There is no such molecule. The researchers identified many genes—2,300 of them, more than a tenth of the insect's genome—
不存在这种分子。研究人员发现了很多基因——2300个，超过这种昆虫基因组的十分之一——

that encode proteins which it secretes while feeding on the vine. These enable it to evade the plant's immune system while diverting resources from its host.
基因编码蛋白质，这些蛋白质是它以藤本植物为食时分泌的。这使它能够避开植物的免疫系统，同时从它的宿主转移资源。

The work now begins of teasing out what each of those genes does, and, ultimately, how phylloxera manipulates a plant and adapts to a new host.
现在的工作是弄清楚每个基因的作用是什么，以及根瘤蚜虫最终如何操控植物并适应新的宿主。

This information may in turn generate new weapons against the creature.
这些信息可能反过来会生成对付该生物的新武器。

That could be valuable in parts of viticulture's New World, such as Australia, where vines remain ungrafted and phylloxera is still a problem.
这在葡萄栽植新世界的部分地区可能很有价值，比如澳大利亚，在这些地方，葡萄藤仍是非嫁接的，并且根瘤蚜虫仍是一个问题。

It might also help if the insect ever evolves the ability to evade the natural resistance of American vine roots
如果这种昆虫进化出了避开美国藤本植物根系的自然抗性的能力，这也可能会有所帮助。

that currently stands between European growers and disaster. For Dr Forneck, this prospect is not outlandish.
目前这种自然抗性时欧洲种植者和灾难之间的屏障。对于Forneck博士，这种预期并不奇怪。

The insect is already adapting to a warmer world, and shifting its range. Further shifts in its physiology are perfectly possible.
这种昆虫已经适应了更温暖的环境，并改变了它的活动范围。进一步的生理变化是完全可能的。