时差N小时 树根及其真菌好友

If I told you there was a large mass of fungus¹ infecting the roots of that lovely pine tree which shades your front lawn, would you be worried? Would you buy a strong fungicide if I said that this fungus survived by sucking valuable sugars, vitamins, and other nutrients³ out of your tree's roots?

可爱的松树在前院的草丛上投下了阴凉。如果这时我告诉你这颗松树的根部感染了大量的真菌，你会感到担心吗？如果我告诉你这种真菌是靠吸收根部的糖、维他命以及其它营养物质来生存，你会买来强力除菌剂除掉它们吗？

Actually, most species of tree and plant are routinely infected by what's known as “mycorrhizal fungi²,” but this is no cause for alarm. We'll learn how trees can actually benefit from their fungal friends on today's moment of science.

事实上，大多种类的树木和植物的根部都会感染菌根真菌，但你没有理由惊慌。在今天的科学时刻我们会一同学习树木如何与它们的真菌朋友相互依存，互惠互利。

Many trees and plants not only host mycorrhizal fungi–they have actually come to depend on them. As the fungi grow, they send fine tentacles⁴ streaming into the soil. These tentacles help channel large amounts of water and nutrients back to the host tree, far more water than the tree would be able to trap with its roots alone.

许多树木和植物不仅仅是菌根真菌的宿主——它们实际上是在依靠这些真菌。随着真菌不断的繁衍，大量细长的触须涌向土壤。这些触须会将大量的水分和营养物质引回宿主树木的身边，这远比树木的根部自身所捕获的水分要多。

One study found that conifers with the fungus are twice as likely to survive a drought as those without. Some mycorrhizal fungi help their host tree in other ways too, secreting⁵ a tree hormone⁶ that causes the roots to grow new root tips, and a hormone that increases the longevity⁷ of these new roots.

一个研究发现有真菌的针叶树比没有真菌的针叶树在干旱中幸存的几率高两倍。有些菌根真菌还能在其他方面帮助宿主树木。它们刺激树木的根部分泌激素，以长出新的根须，这种激素也能延长新树根的寿命。

Other fungi release natural antibiotics⁸ into the soil, further protecting the tree. In fact, the seedlings⁹ of many tree species will die if fungus does not develop around their roots during their first year of growth.

还有一些真菌会在土壤中释放天然的抗生素，进一步保护树木。实际上，如果幼树在第一年的生长期中没有真菌寄生在其根部，那么大量的幼树都会死亡。

This is a striking example of the biological concept of symbiosis¹⁰, in which two or more unrelated species have co-evolved and now depend on each other for survival. It shows us just how interconnected the delicate web of life is. Which covers our planting earth.

生物概念下的共生现象是指两种或者多种不相关联的物种共同进化，互相依存，而树木与真菌就是一个显著的例子。它向我们展示了生命之网的内在联系。生命之网虽然脆弱，但却蕴育了繁茂的地球。

1 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。

2 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。

3 nutrients   

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》

4 tentacles   

n.触手( tentacle的名词复数 )；触角；触须；触毛

参考例句：

• Tentacles of fear closed around her body. 恐惧的阴影笼罩着她。
• Many molluscs have tentacles. 很多软体动物有触角。 来自《简明英汉词典》

5 secreting   

v.（尤指动物或植物器官）分泌( secrete的现在分词 )；隐匿，隐藏

参考例句：

• It is also an endocrine gland secreting at least two important hormones. 它也是一种内分泌腺，至少分泌二种重要的激素。 来自辞典例句
• And some calcite-secreting organisms also add magnesium to the mix. 有些分泌方解石的生物，会在分泌物中加入镁。 来自互联网

6 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

7 longevity   

n.长命；长寿

参考例句：

• Good habits promote longevity.良好的习惯能增长寿命。
• Human longevity runs in families.人类的长寿具有家族遗传性。

8 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

9 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》

10 symbiosis   

n.共生（关系），共栖

参考例句：

• They live in a symbiosis with governments that they are financing.他们与他们服务的政府互利共存。
• The symbiosis between social values and political structure has produced extraordinary achievement.社会价值观念和政治结构的共生现象带来了非凡的成就。