经济学人下载:农业--不在灰尘中成长,就在灰尘中灭亡(1)

Evolution and agriculture 

进化和农业

Good catch 

丰收

Some crops can absorb phosphorus from dust 

有些作物能从尘土中吸收磷 

Wheat was among the first plants to be domesticated and is now the most widespread crop in the world. It thus sounds unlikely there would be much left to learn about what makes it thrive. Yet, some 12,000 years after relations between people and wheat began, a wheat plant has been caught doing something unexpected. It helped itself to a dose of much-needed phosphorus when its leaves received a coating of desert dust. 

小麦是最早被驯化的植物之一，现在已经是非常普遍的农作物。所以，小麦还有很大的发展空间这种事情听起来似乎不太可能。然而，在人类和小麦建立联系的大概12000年之后，人们发现小麦做了一些不可思议的事情：当它的叶子被覆盖上一层沙尘时，它竟帮自己获得了所需的磷。

The plant(or, rather, plants)in question were in the care of Avner Gross of the Ben Gurion University of the Negev, in Israel. As Dr Gross told this year's meeting of the American Geophysical Union, which took place online during the first half of December, his study was prompted by hikes he had taken near Neve Shalom, his home village in the Judean Hills. On these, he often noticed plant leaves completely covered in dust that had been carried there by sand storms from the Sahara desert. 

我们所说的这株植物(或者更确切地说，多株植物)由以色列内盖夫本古里安大学的阿夫纳·格罗斯照料。格罗斯博士在今年12月上半月在线举行的美国地球物理联盟会议上说，他的研究受自己在犹太山的家乡尼夫沙洛姆附近徒步旅行时所启发。那会儿他经常注意到，植物的叶子被撒哈拉沙漠的沙尘暴带到那里的灰尘完全覆盖。

It occurred to him that this dust might not be the light-blocking nuisance it appeared at first sight. It could, on the contrary, be beneficial because of the growth-enhancing elements such as phosphorus which it contained. Until then, botanists had assumed that phosphorus in dust landing on a plant was of little value, because it is locked up in an insoluble mineral called apatite. This makes it unavailable for absorption. Dr Gross, however, reasoned that plants which had evolved near deserts, the source of almost all naturally occurring dust in the atmosphere, might well have evolved a way to exploitit. 

之后他想到，那些灰尘可能并不是一眼望去的那种阻挡光线的令人生厌的东西。相反，它们可能是有益的，因为灰尘里含有某些能够促进生长的元素，比方说磷。在此之前，植物学家一直认为落在植物上的灰尘中的磷并没有什么价值，因为它被锁在一种叫做磷灰石的不溶矿物中，无法被吸收。然而格罗斯博士推断，沙漠是大气中几乎所有自然产生的灰尘的来源，而那些生长在沙漠附近的植物很可能已经进化出了一种利用沙漠的方式，

He and two colleagues, Sudeep Tiwari, also at Ben Gurion, and Ran Erel of the Gilat Research Centre, therefore started experimenting with a pair of species, wheat and chickpeas (the world's 17th most planted crop), that both came originally from the Middle East. As a control, they also raised some maize, a plant from the Americas that evolved in farless dusty surroundings. 

因此，他和他的两个同事，即同样在本古里安工作的苏迪普·蒂瓦里和吉莱特研究中心的拉恩·艾勒伊，开始用来自中东的农作物小麦和鹰嘴豆(世界上种植最多的农作物里排行17)这两个物种进行实验。此外，他们还种植了玉米作为对照，玉米是一种来自美洲的植物，在尘土较少的环境中进化而来。