时间:2018-12-15 作者:英语课 分类:VOA慢速英语2009年(十)月


英语课

This is the VOA Special English Agriculture Report.


Plant breeders and genetic 2 engineers keep working to give crops the strength to resist threats like insects, diseases, droughts or floods.


But before you can resist a threat, you need to understand it.


We told you last week about a newly completed genetic map of the organism that causes late blight 3. That disease led to starvation in Ireland from potato shortages in the middle of the eighteen hundreds. The new genome could lead to better ways to protect potatoes, tomatoes and other crops.


Science may supply a stronger crop. Yet that does not always guarantee demand.


Nik Grunwald from the United States Agriculture Department worked on the international team that completed the genome. He says it is possible to grow potatoes that resist late blight. But these may not look like Russet potatoes. And most American farmers grow Russets because, as Nik Grunwald puts it, "that is where the demand is."


Another example of scientific progress involves a natural bacterium 4 known as Bt. Bt is used as a pesticide 5 to fight cotton bollworms, corn borers and other pests. Scientists have found a way to grow cotton plants that contain a Bt gene 1, reducing the need for pesticides 6. But sometimes, when one problem gets solved, another one appears.


In China, some farmers and researchers blame a decrease in pesticide use for an increase in pests unaffected by Bt. Also, there are concerns that some organisms could begin to resist the plants designed to resist them.


And scientists are reporting this week on what they call the "indirect costs" of a virus-resistance gene in Cucurbita. This is the species of squash that includes pumpkins 7 and gourds 8. The scientists say virus-resistant transgenic squash are grown throughout the United States and much of Mexico.


The genetically 9 engineered squash are usually larger and healthier than wild squash. But a three-year study showed that beetles 10 like to feed more on the transgenic plants, increasing cases of wilt 11 disease. The report by a team from the United States and China appears in the Proceedings 12 of the National Academy of Sciences.


The researchers point out that gene flow between crops and their wild relatives is common and difficult to contain. They note concerns that wild plants could, as a result, gain genetically engineered resistances. And these could affect the natural balance in their environment.


And that's the VOA Special English Agriculture Report, written by Jerilyn Watson. I'm Bob Doughty 13.



1 gene
n.遗传因子,基因
  • A single gene may have many effects.单一基因可能具有很多种效应。
  • The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
2 genetic
adj.遗传的,遗传学的
  • It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
  • Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。
3 blight
n.枯萎病;造成破坏的因素;vt.破坏,摧残
  • The apple crop was wiped out by blight.枯萎病使苹果全无收成。
  • There is a blight on all his efforts.他的一切努力都遭到挫折。
4 bacterium
n.(pl.)bacteria 细菌
  • 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。
5 pesticide
n.杀虫剂,农药
  • The pesticide was spread over the vegetable plot.菜田里撒上了农药。
  • This pesticide is diluted with water and applied directly to the fields.这种杀虫剂用水稀释后直接施用在田里。
6 pesticides
n.杀虫剂( pesticide的名词复数 );除害药物
  • 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》
7 pumpkins
n.南瓜( pumpkin的名词复数 );南瓜的果肉,南瓜囊
  • I like white gourds, but not pumpkins. 我喜欢吃冬瓜,但不喜欢吃南瓜。 来自《简明英汉词典》
  • Then they cut faces in the pumpkins and put lights inside. 然后在南瓜上刻出一张脸,并把瓜挖空。 来自英语晨读30分(高三)
8 gourds
n.葫芦( gourd的名词复数 )
  • Dried gourds are sometimes used as ornaments. 干葫芦有时用作饰品。 来自《简明英汉词典》
  • The villagers use gourds for holding water. 村民们用葫芦盛水。 来自《简明英汉词典》
9 genetically
adv.遗传上
  • All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
  • Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物
10 beetles
n.甲虫( beetle的名词复数 )
  • 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》
11 wilt
v.(使)植物凋谢或枯萎;(指人)疲倦,衰弱
  • Golden roses do not wilt and will never need to be watered.金色的玫瑰不枯萎绝也不需要浇水。
  • Several sleepless nights made him wilt.数个不眠之夜使他憔悴。
12 proceedings
n.进程,过程,议程;诉讼(程序);公报
  • He was released on bail pending committal proceedings. 他交保获释正在候审。
  • to initiate legal proceedings against sb 对某人提起诉讼
13 doughty
adj.勇猛的,坚强的
  • Most of successful men have the characteristics of contumacy and doughty.绝大多数成功人士都有共同的特质:脾气倔强,性格刚强。
  • The doughty old man battled his illness with fierce determination.坚强的老人用巨大毅力与疾病作斗争。
学英语单词
abrupt deceleration vehicle
achromachia
apacked
Auricularia auricula
australian pitcher plants
Avast hauling!
bepuff
beslabbered
buffered filter paper
Bulgarevo
buoyancy curve
cadmium sulphide
Catalpa L.
chrysandiol
Congo floor maggot
DC electric propulsion plant
defilippis
ecomil
eelworms
egg-white protein
engineering geological classification of rock mass
engraftment
eusebia
Evangelista Torricelli
evasion error
exponential expansion
fallopiuss
field-sequential system
fight up to the last ditch
final-year
fotp
geard
get a cold reception
guide block
hangava
hansler
harbo(u)r operational zone
Hemitrichia
heteragraft
high velocity liquid jet machining
high-voltage glow tube
hormone culture-medium
hydnocarpus wightiana bl.
hytners
I fear
illtempered
Indosasa patens
information given in a questionnaire
information retrieval system evaluation
initial steam admission
insoluble solides
irrigated soil
Kinnitty
Kolomonyi
lactic-acid
Lithocarpus
LVTR
magnetohydrodynamic propulsion plant
manganese(iv) silicide
marmalade trees
mattings
mesengium
microvoltmeter
monetizability
nanocavity
Newry Canal
non-zero restriction
oil lubricating system
onishi
optic integrated circuit
pellet mouldings
PGS (program generation system)
plesiotrochus acutangulus
prepacked with grease
prevailing price
prunus mume sieb.et zucc.var.tonsa rehd.
prunus mume var.bungo mak.
purplestreak alstroemeria
rag out
residentiaries
reverse pinocytosis
rizzle
ruscombe
sample grid reference
Sandnessjφen
sandy mushrooms
secondary process
sent out
sound intensity decay
sprawlings
statistical weights
strapped multiresonator circuit
subfraction
Suttsu
the top of
tightness of stitches
top-fired boiler
triangulation balloon
unconquering
unfamiliarity
uredo cryptogrammes
Voidable Civil Act