Developing Wheat Resistant to Leaf Rust

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59 美国科学家正试图培育抗叶锈病小麦

DATE=6-19-01
TITLE=AGRICULTURE REPORT - Developing Wheat Resistant¹ to Leaf Rust²  BYLINE=George Grow

(Start at 59") This is Bill White with the VOA Special English AGRICULTURE REPORT. 
American research scientists are using information from (1) genetic⁴ material to make wheat more (2) resistant to leaf (3) rust.  The researchers have identified small pieces of genetic material in wheat plants that are linked to leaf rust resistance. These markers are made of genetic material called D-N-A. The researchers plan to use these markers to develop wheat with (4) longer-lasting resistance to the disease. 
Gina Brown-Guedira of the Agricultural Research Service identified the genetic markers in (5) wheat.  Her team in Manhattan, Kansas is collecting the information.  Agricultural Research magazine published a report on the project.
Leaf rust is a threat to wheat production in many areas of the United States. More than five percent of all hard winter wheat grown in the north central part of the country was lost to leaf rust during the Nineteen-Nineties.  The disease cost farmers about one-hundred-fifty-million dollars in crop losses each year.  The disease also seriously affects the quality of products made from wheat flour.
A (6) fungus⁵ causes wheat leaf rust.  Plants infected with the organism develop small (7) reddish or orange (8) spores⁶ on their leaves. 
In the past, researchers developed wheat plants with different resistance levels to wheat leaf rust.  Such plants had only a single leaf rust resistance gene³.  The plants usually began to lose their (9) effectiveness against the disease after a few years. 
Mizz Brown-Guedira is (10) combining leaf rust resistance found in two ancestors of modern wheat.  One plant, known as goatgrass, grows in areas from (11) Afghanistan to (12) Syria.  The other comes from (13) Iran, (14) Iraq and Turkey.  The researchers hope genes⁷ from the two plants can be combined and moved into plant cells.  They say such cells could be used to develop wheat resistant to the disease.
Scientists currently must study genetic material in a plant to confirm the (15) presence of more than one resistance gene.  Such genetic studies are a slow process, however. 
Mizz Brown-Guedira and her team can test a plant for the presence of several D-N-A markers that are linked to the resistance genes.  They say their research can speed the work of developing plants with resistance genes.
This VOA Special English AGRICULTURE REPORT was written by George Grow. This is Bill White.

(1) genetic [dVi`netik] adj.遗传的, 起源的
(2) resistant [ri`zistEnt] adj.抵抗的, 有抵抗力的
(3) rust [rQst] n.铁锈
(4) longer-lasting adj. 持久的
(5) wheat [wi:t] n.小麦, 小麦色, 淡黄色, 朴实的人
(6) fungus [ `fQN^Es]n.菌类, 蘑菇
(7) reddish [`rediF] adj.微红的, 略带红色的
(8) spore [spC:] n.孢子
(9) effectiveness [i`fektivnis] n.效力
(10) combine [kEm`bain] v.(使)联合, (使)结合
(11) Afghanistan [Af`gAnistEn] n.阿富汗(西南亚国家)
(12) Syria [`siriE] n.叙利亚共和国(西南亚国家)
(13) Iran [i`rB:n] n.伊朗
(14) Iraq [i`rB:k] n.伊拉克共和国
(15) presence [ `prezns] n.存在

 

1 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

2 rust   

n.锈；v.生锈；(脑子)衰退

参考例句：

• She scraped the rust off the kitchen knife.她擦掉了菜刀上的锈。
• The rain will rust the iron roof.雨水会使铁皮屋顶生锈。

3 gene   

n.遗传因子，基因

参考例句：

• 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。

4 genetic   

adj.遗传的，遗传学的

参考例句：

• 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。

5 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。

6 spores   

n.（细菌、苔藓、蕨类植物）孢子( spore的名词复数 )v.（细菌、苔藓、蕨类植物）孢子( spore的第三人称单数 )

参考例句：

• Ferns, mosses and fungi spread by means of spores. 蕨类植物、苔藓和真菌通过孢子传播蔓生。
• Spores form a lipid membrane during the process of reproducing. 孢于在生殖过程中形成类脂膜。 来自英汉非文学 - 生命科学 - 预防生物武器

7 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪