时间:2018-12-16 作者:英语课 分类:2013年VOA慢速英语(七)月


英语课

 


AS IT IS 2013-07-15 The Fight to Protect Cassava Plants



Hello, and welcome once again to “As It Is,” our daily show for people learning everyday American English.


I’m Christopher Cruise in Washington.


Today on the program, we tell about the moringa oleifera plant. It feeds millions, but many people have never heard of it.


"It’s sometimes viewed as one of the most nutritious 1 plants in the world.”


Protecting Cassava


But first, we tell about efforts to fight a disease that is spreading and attacking a plant that is important for Africa.


Scientists and agricultural experts recently met in Italy to talk about how to fight cassava disease. A virus that has been killing 2 this important crop in East Africa was recently discovered to have spread to West Africa. Experts are now concerned that it could spread rapidly throughout West Africa, including Nigeria. Nigeria is the world’s largest producer and consumer of cassava.


Cassava is a tropical root vegetable that requires little work. It grows well in poor-quality soil and high temperatures. The roots are full of carbohydrates 3, vitamins and minerals.



Cassava can also be used as an industrial starch 4 to produce plywood, textiles and paper. Cassava is sometimes called a miracle crop for Africa. But diseases have been a problem for a century.


One particularly deadly virus is cassava brown streak 5 disease. It began infecting cassava fields in East Africa 10 years ago. Now it has spread as far west as the Democratic Republic of Congo.


Brown streak disease is spread in two ways: by white flies and by infected stem cuttings. Farmers use these cuttings instead of seeds to plant their fields.


Claude Fauquet is a plant virus expert. He heads the Global Cassava Partnership 6 for the 21st Century.


“The disease is not very obvious on the plant itself. The plants are, are growing fairly well, but the disease is obvious on the roots when they harvest -- but when they harvest, it’s too late. So, in short, there is really nothing that farmers can do, and therefore solutions have to come from scientists and from different organizations that would be capable of offering farmers, you know, virus-free material.”



Mr. Fauquet says scientists are experimenting with a virus-resistant cassava plant in Tanzania. They either combine it with other virus-resistant strains of the plant or genetically-engineer new ones in the laboratory. They then must go village by village to get farmers to plant it.


Mr. Fauquet says this kind of effort has been successful against cassava mosaic 7 disease. That is the most common cassava disease in Africa. It has spread throughout the continent. But it mainly damages the plant, not the root. Farmers can usually save some of the plant. Mr. Fauquet says that is not the case with brown streak disease, which kills the root.


Experts say brown streak disease could reduce cassava production in Africa by 50 percent. As many as 300 million Africans could be affected 8.


“You would have explosion of the disease, and, and maybe we would need a decade before we could respond and offer farmers, and to millions of farmers, to offer solutions, so, the magnitude of the problem would be gigantic.


Claude Fauquet says if even one farmer shares infected stem cuttings, the disease will continue to spread.    


The Most Important Plant You May Never Have Heard Of…


A listener in Nigeria, Gaddafi Adamu, has asked us to talk about the moringa oleifera plant. This kind of shrub 9 or tree is grown for food and other uses. We spoke 10 with Gerry Moore, a plant expert at the Natural Resources Conservation Service, part of the United States Department of Agriculture. He told us the plant is high in protein and rich in vitamins and minerals. 


“It’s sometimes viewed as one of the most nutritious plants in the world. It has a lot of nutritional 11 values, and much of the plant can be used for food. So it’s not just the fruit that can be taken, but it is an unusual plant in that the leaves, the fruits, the roots and the seeds are all used in one way or another for food.”



The plant is known by different names around the world. Moringa oleifera is native to the foothills of the Himalayas, from Pakistan to eastern India. Because it is native to that area, much of the research on the plant has been done by scientists in Pakistan and India.


Its native range is narrow, but the plant is grown throughout the world, so its introduced range is broad. In the United States, it has been introduced in Hawaii, Florida and Puerto Rico.


Gerry Moore from the Agriculture Department says the plant doesn’t like the cold, but it can grow in many areas.


“It cannot tolerate freezing, and it has pretty high temperature tolerances 13, maybe up to about 120 degrees Fahrenheit 14, 49 degrees Celsius 15. And so it can grow, you know, in areas where you do not get any excessive freezing. And it also has significant drought tolerance 12, so it can be grown in quite dry areas. It can also grow in higher moisture areas, where you get rainfall of over 85 inches a year. So it has a lot of tolerances that are quite good for growing it in a large part of the world, but you’re not going to find it where there’s excessive freezing.”


He says the plant can be used for different kinds of food.


“The leaves can be boiled and can be eaten in curry 16 dishes. The fruit is usually skinned so you take the skin or the peel off and it can be sliced and eaten, either cooked or pickled, and it has a taste very similar to asparagus.”


The roots of the plant can be dug up, peeled and used as a seasoning 17 in the same way as horseradish. Moringa oleifera is related to mustard, so it can give a sharp taste. The seeds in the fruit can be fried and taste like peanuts. The seeds are rich in oil that can be used for salad oil. But the bark of the moringa oleifera tree can be poisonous, so be sure to remove it.


Versatile 18 Songstress


Finally, Linda Ronstadt, a pop superstar of the 1970s and 80s is celebrating a birthday this week.


She was born July 15th, 1946.



She is known for such hits as “You’re No Good.”


She has recorded in almost every musical style, including rock, folk, country, jazz and big band.


Linda Marie Ronstadt is now 67 years old.


We hope you enjoyed our program today.


I’m Christopher Cruise, and that’s “As It Is” on The Voice of America.








1 nutritious
adj.有营养的,营养价值高的
  • Fresh vegetables are very nutritious.新鲜蔬菜富于营养。
  • Hummingbirds have discovered that nectar and pollen are very nutritious.蜂鸟发现花蜜和花粉是很有营养的。
2 killing
n.巨额利润;突然赚大钱,发大财
  • Investors are set to make a killing from the sell-off.投资者准备清仓以便大赚一笔。
  • Last week my brother made a killing on Wall Street.上个周我兄弟在华尔街赚了一大笔。
3 carbohydrates
n.碳水化合物,糖类( carbohydrate的名词复数 );淀粉质或糖类食物
  • The plant uses the carbohydrates to make cellulose. 植物用碳水化合物制造纤维素。 来自《简明英汉词典》
  • All carbohydrates originate from plants. 所有的碳水化合物均来自植物。 来自辞典例句
4 starch
n.淀粉;vt.给...上浆
  • Corn starch is used as a thickener in stews.玉米淀粉在炖煮菜肴中被用作增稠剂。
  • I think there's too much starch in their diet.我看是他们的饮食里淀粉太多了。
5 streak
n.条理,斑纹,倾向,少许,痕迹;v.加条纹,变成条纹,奔驰,快速移动
  • The Indians used to streak their faces with paint.印第安人过去常用颜料在脸上涂条纹。
  • Why did you streak the tree?你为什么在树上刻条纹?
6 partnership
n.合作关系,伙伴关系
  • The company has gone into partnership with Swiss Bank Corporation.这家公司已经和瑞士银行公司建立合作关系。
  • Martin has taken him into general partnership in his company.马丁已让他成为公司的普通合伙人。
7 mosaic
n./adj.镶嵌细工的,镶嵌工艺品的,嵌花式的
  • The sky this morning is a mosaic of blue and white.今天早上的天空是幅蓝白相间的画面。
  • The image mosaic is a troublesome work.图象镶嵌是个麻烦的工作。
8 affected
adj.不自然的,假装的
  • She showed an affected interest in our subject.她假装对我们的课题感到兴趣。
  • His manners are affected.他的态度不自然。
9 shrub
n.灌木,灌木丛
  • There is a small evergreen shrub on the hillside.山腰上有一小块常绿灌木丛。
  • Moving a shrub is best done in early spring.移植灌木最好是在初春的时候。
10 spoke
n.(车轮的)辐条;轮辐;破坏某人的计划;阻挠某人的行动 v.讲,谈(speak的过去式);说;演说;从某种观点来说
  • They sourced the spoke nuts from our company.他们的轮辐螺帽是从我们公司获得的。
  • The spokes of a wheel are the bars that connect the outer ring to the centre.辐条是轮子上连接外圈与中心的条棒。
11 nutritional
adj.营养的,滋养的
  • A diet lacking in nutritional value will not keep a person healthy.缺乏营养价值的饮食不能维持人的健康。
  • The labels on food products give a lot of information about their nutritional content.食品上的标签提供很多关于营养成分的信息。
12 tolerance
n.宽容;容忍,忍受;耐药力;公差
  • Tolerance is one of his strengths.宽容是他的一个优点。
  • Human beings have limited tolerance of noise.人类对噪音的忍耐力有限。
13 tolerances
n.宽容( tolerance的名词复数 );容忍;忍耐力;偏差
  • Not only must the centers decrease, but the tolerances to produce quality bonds must also decrease. 不仅中心间距减少,而且产生优质连接的容限也必须减少。 来自辞典例句
  • Then analysis the reasons and influencing factors of such tolerances. 最后分析出现误差的原因以及影响因素。 来自互联网
14 Fahrenheit
n./adj.华氏温度;华氏温度计(的)
  • He was asked for the boiling point of water in Fahrenheit.他被问到水的沸点是华氏多少度。
  • The thermometer reads 80 degrees Fahrenheit.寒暑表指出华氏80度。
15 Celsius
adj.摄氏温度计的,摄氏的
  • The temperature tonight will fall to seven degrees Celsius.今晚气温将下降到七摄氏度。
  • The maximum temperature in July may be 36 degrees Celsius.七月份最高温度可能达到36摄氏度。
16 curry
n.咖哩粉,咖哩饭菜;v.用咖哩粉调味,用马栉梳,制革
  • Rice makes an excellent complement to a curry dish.有咖喱的菜配米饭最棒。
  • Add a teaspoonful of curry powder.加一茶匙咖喱粉。
17 seasoning
n.调味;调味料;增添趣味之物
  • Salt is the most common seasoning.盐是最常用的调味品。
  • This sauce uses mushroom as its seasoning.这酱油用蘑菇作调料。
18 versatile
adj.通用的,万用的;多才多艺的,多方面的
  • A versatile person is often good at a number of different things.多才多艺的人通常擅长许多种不同的事情。
  • He had been one of the game's most versatile athletes.他是这项运动中技术最全面的运动员之一。
学英语单词
Achlya
angel fallss
anharmonic oscillator
argininoxytocin
artificial load
Athabaskan
axe stone
B, b
beat to the draw
blaze away
Blomstermåla
bo trees
boccas
Brabantian
carbon nanofibre
cheese paraffin
chocard
chunter
classification problem
coated chip
commissionaire
community power
consulation
Cornforth, Sin John Warcap
curve versine
deprofessionalised
descriptive metaphysics
dimensional regularization
dracaena reflexa
educational display
electrode admittance
electrosmosis
factors in
Fominskoye
general average loss
genus hippotraguss
Gloger
Gressoney-la-Trinité
hackbushier
hawk weed
heftinesses
hemianopia
herborise
Hoblyn
homopurine
immunopathologies
infantile amaurotic idiocy
initial location
internal circulation
IT Infrastructure Library
Kinmaw
knightliest
legendary character
lter
meteorologic post
milkpox
mocyon
mosalas
NCNCA
nodi lymphatici centrales
nylon-string guitars
obliterating phlebitis
old ship
Oliver Shield
orthostichous
Oum el Achar
overcount
patient type
polymyositic
poor workmanship
PRLX
ramallo
reamend
remission of schizophrenia
responser time
right to handle imports and exports
rowelled
RTEA
saprophagous organisms
sarais
seizure of plunger
self-synchronize
serolipase
singabler
skew (in facsimile)
slots in
standard hoisting rope
stencil-like
studio backgrounds
submonoids
succentor
supply to seal
surface macro texture
timing-gear gasket
Timiskaming group
triatomic base
triterpenoid saponin
Tswaane
tunelike
valuation at cost or market
Vema Trench
wagonbuilders