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科学美国人60秒 SSS 从空气中获取肥料的玉米品种

时间:2019-09-29 06:40:27

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(单词翻译)

This is Scientific American — 60-Second Science. I'm Christopher Intagliata.

这里是科学美国人——60秒科学。我是克里斯托弗·因塔利亚塔。

Plants need three things to grow: air, water and nutrients1. Farmers usually take care of the last bit by fertilizing2 their fields. But now scientists have found a type of corn that seems to thrive on air and water alone.

植物生长需要三种东西:空气、水和养分。农民一般通过给田地施肥来提供养分。但是现在科学家发现,有种玉米似乎只靠空气和水就能生长。

"This has been sort of the holy grail, you know, if only I could grow corn and not put 200 pounds of nitrogen on it." Allen Van Deynze is a plant breeder at the University of California, Davis, and part of a team that analyzed3 this one corn's unusual ability.

“如果能不用施200磅氮肥就能让玉米生长,那就像是圣杯一样。”艾·范·德恩兹是加州大学戴维斯分校的植物育种专家,他所在的团队对这种玉米不同寻常的能力进行了分析。

The corn variety hails from Oaxaca, Mexico, where it typically grows in nitrogen-poor soils. Nitrogen is needed for proteins, DNA4 and the chlorophyll that let plants perform photosynthesis5. But the Oaxacan corn does well despite the bad soil, and with little or no fertilization.

这种玉米源自墨西哥瓦哈卡州,通常在该州贫瘠的土壤中生长。氮是蛋白质、DNA和让植物进行光合作用的叶绿素所必需的。但是,尽管生长在极少甚至没有肥料的贫瘠土壤中,瓦哈卡州玉米依旧长得很好。

The plants pull off this trick via thick, red, aerial roots that protrude6 from its stem—above the ground—that ooze7 out a clear goo packed with sugars. That slime is the perfect habitat for nitrogen-fixing bacteria: a sugar-rich, oxygen-poor environment where the microbes transform nitrogen gas into a soluble8 form the corn plant can use. It's an above-ground version of the nitrogen-fixation you might usually think of as happening in the underground roots of legumes, like peas and beans.

玉米通过其粗壮且呈红色的气生根来实现这一良好态势,这种气生根从玉米茎地表部分伸出,分泌出富含糖分的透明黏液。这种黏液是固氮细菌的完美栖息地:这是一种多糖且缺氧的环境,细菌在此将氮气转化为玉米植株可以利用的可溶性形式。这是一种发生在地表的固氮形式,可能你通常认为它发生在豌豆和蚕豆等豆类的地下根部。

The researchers demonstrated the corn plants' talent by exposing them to labeled isotopes9 of nitrogen. And they were able to track the movement of the distinctly identifiable nitrogen atoms from the air, to the root, and into the plant. This pathway allows the corn to obtain up to 80 percent of its nitrogen straight out of the air. The details are in the journal PLOS Biology.

研究人员让玉米接触带标记的氮同位素,以此来证明其才能。他们能追踪到有明显不同的氮元子的运动轨迹,从空气到根部最后进入玉米植株。这一路径使玉米中多达80%的氮可以直接从空气中获得。该研究具体内容刊登在《美国公共科学图书馆·生物学》期刊上。

Van Deynze says early plant breeders may have inadvertently got rid of corn's nitrogen-fixing proficiency10 long ago. "When early man made some selections for, probably, you know, bigger ears, higher yield, perhaps they lost this ability along the way. And we have the opportunity perhaps to bring it back."

范·德恩兹表示,早期植物育种家可能很早之前就在无意中去除了玉米的固氮能力。“当早期人类选择谷穗更大、产量更高的玉米时,也许就在这个过程中使玉米失去了固氮能力。而我们也因此得到了可以恢复这种能力的机会。”

Thanks for listening for Scientific American — 60-Second Science. I'm Christopher Intagliata.

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。


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点击收听单词发音收听单词发音  

1 nutrients 6a1e1ed248a3ac49744c39cc962fb607     
n.(食品或化学品)营养物,营养品( nutrient的名词复数 )
参考例句:
  • a lack of essential nutrients 基本营养的缺乏
  • Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
2 fertilizing 79a37a7878a3e9b841687c9b9748dd60     
v.施肥( fertilize的现在分词 )
参考例句:
  • Sometimes the preliminary step must be taken of reducing weed population before fertilizing. 有时候,在施肥之前,必须采取减少杂草密度的预备性步骤。 来自辞典例句
  • The self fertilizing garden can also be planted in raised beds. 自我施肥的菜园也可以在苗圃床中种植。 来自互联网
3 analyzed 483f1acae53789fbee273a644fdcda80     
v.分析( analyze的过去式和过去分词 );分解;解释;对…进行心理分析
参考例句:
  • The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
  • The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程,因为对他来说,爱是个不可分析的迷。 来自《简明英汉词典》
4 DNA 4u3z1l     
(缩)deoxyribonucleic acid 脱氧核糖核酸
参考例句:
  • DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
  • Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。
5 photosynthesis A2Czp     
n.光合作用
参考例句:
  • In apple trees photosynthesis occurs almost exclusively in the leaves.苹果树的光合作用几乎只发生在叶内。
  • Chloroplasts are the structures in which photosynthesis happens.叶绿体就是光合作用发生的地方。
6 protrude V0mzm     
v.使突出,伸出,突出
参考例句:
  • The tip of her tongue was protruding slightly.她的舌尖微微伸出。
  • A huge round mass of smooth rock protruding from the water.一块光滑的巨型圆石露出水面。
7 ooze 7v2y3     
n.软泥,渗出物;vi.渗出,泄漏;vt.慢慢渗出,流露
参考例句:
  • Soon layer of oceanic ooze began to accumulate above the old hard layer.不久后海洋软泥层开始在老的硬地层上堆积。
  • Drip or ooze systems are common for pot watering.滴灌和渗灌系统一般也用于盆栽灌水。
8 soluble LrMya     
adj.可溶的;可以解决的
参考例句:
  • These tablets are soluble in water.这些药片可在水中溶解。
  • Camphor is soluble in alcohol.樟脑在酒精中可以溶化。
9 isotopes 92848c3160703e48dc3b552ac6f54115     
n.同位素;同位素( isotope的名词复数 )
参考例句:
  • the many isotopes of carbon 碳的诸多同位素
  • Tritium is one of the mildest radioactive isotopes. 氚是最和缓的放射性同位素之一。 来自《简明英汉词典》
10 proficiency m1LzU     
n.精通,熟练,精练
参考例句:
  • He plied his trade and gained proficiency in it.他勤习手艺,技术渐渐达到了十分娴熟的地步。
  • How do you think of your proficiency in written and spoken English?你认为你的书面英语和口语熟练程度如何?

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