Question

    Although it has been revealed in recent years that plants are capable of seeing, hearing and smelling, they are still usually thought of as silent. But now, for the first time, they have been recorded making ultrasonic (超声的) cries when stressed, which researchers say could open up a new field of precision agriculture where farmers listen for water-starved crops.

Itzhak Khait and his colleagues at Tel Aviv University in Israel found that tomato and tobacco plants made cries at frequencies humans cannot hear when stressed by a lack of water or when their stem it cut.

Microphones placed 10 centimetres from the plants picked up sounds in the ultrasonic range of 20 to 100 kilohertz, which the team says insects and some mammals would be capable of hearing and responding to from as far as 5 metres away. A moth may decide against laying eggs on a plant that sounds water-stressed, the researchers suggest. Plants could even hear that other plants are short of water and react accordingly, they speculate (推断).

On average, drought-stressed tomato plants made 35 sounds an hour, while tobacco plants made 11. When plant stems were cut, tomato plants made an average of 25 sounds in the following hour, and tobacco plants 15. Unstressed plants produced fewer than one sound per hour, on average.

It is even possible to distinguish between the sounds to know what the stress is. The researchers trained a machine-learning model to recognize between the plants’ sounds and the wind, rain and other noises of the greenhouse, correctly identifying in most cases whether the stress was caused by dryness or a cut, based on the sound’s intensity and frequency. Water-hungry tobacco appears to make louder sounds than cut tobacco, for example.

Enabling farmers to listen for water-stressed plants could “open a new direction in the field of precision agriculture”, the researchers suggest. They add that such an ability will be increasingly important as climate change exposes more areas to drought.

“The suggestion that the sounds that drought-stressed plants make could be used in precision agriculture seems feasible (可行的) if it is not too costly to set up the recording in a field situation,” says Anne Visscher at the royal Botanic Gardens, Kew, in the UK.

She warns that the results can’t yet be broadened out to other stresses, such as salt or temperature, because these may not lead to sounds. In addition, there have been no experiments to show whether moths or any other animal can hear and respond to the sounds the plants make, so that idea remains based on guesses for now, she says.

1.The experiment by researchers at Tel Aviv University shows that________.

A.tomato plants cry more often than tobacco when hurt

B.plant sounds can be heard by plants quite far away

C.humans can hear water-hungry plants crying

D.moths like laying eggs on stressed plant

2.What is Anne Visscher’s attitude towards the finding of the experiment?

A.Disappointed B.Cautious. C.Appreciative. D.Optimistic.

3.Taking advantage of the new research finding,farmers can________.

A.harvest crops in time B.reduce greenhouse effects

C.diagnose plant condition faster D.detect and remove insects easily

4.Which of the following would be the best title for the passage?

A.Plants get stressed Just Like Us.

B.Sounds of Plants Detected Far Away.

C.Cries of plants break Farmers’Hearts

D.Plants scream in the presence of stress

Answer

1.A

2.B

3.C

4.D

【解析】

本文是说明文。研究表明，植物在受到缺水或者被砍断时的压力时，它们会发出尖叫声。这开创了精准农业的一个新领域。

1.

细节理解题。根据第四段中“When plant stems were cut, tomato plants made an average of 25 sounds in the following hour, and tobacco plants 15.（当植物茎秆被切断后，番茄植株在接下来的一小时内平均发出25种声音，而烟草植株发出15种声音。）”可知，研究人员的实验显示番茄植株受到伤害时比烟草植株更容易发出尖叫声。故选A项。

2.

推理判断题。第八段中提到Anne Visscher所说的话“She warns that the results can’t yet be broadened out to other stresses, such as salt or temperature, because these may not lead to sounds. In addition, there have been no experiments to show whether moths or any other animal can hear and respond to the sounds the plants make, so that idea remains based on guesses for now, she says.（她警告说，这个结果还不能扩展到其他压力，比如盐分或温度，因为这些可能不会产生声音。此外，还没有实验证明飞蛾或其他动物是否能听到植物发出的声音并作出反应，所以目前这个想法仍是基于猜测。）”根据其中的“the results can’t yet be broadened …there have been no experiments to show ….so that idea remains based on guesses …”由此可以推断，Anne Visscher对实验结果持谨慎的态度。故选B项。

3.

推理判断题。第六段中提到“Enabling farmers to listen for water-stressed plants could “open a new direction in the field of precision agriculture”, the researchers suggest.They add that such an ability will be increasingly important as climate change exposes more areas to drought.（研究者们认为，让农民能够听到缺水植物的声音可能“在精准农业领域会开辟一个新方向”。他们补充说，随着气候变化使更多地区面临干旱，这种能力将变得越来越重要。）”由此可以推断，这一新的发现让农民能够听到缺水植物的声音，农民就可以快速判断植物当前处于缺水的状况。故选C项。

4.

主旨大意题。通读全文，文章第一段提到“they have been recorded making ultrasonic (超声的) cries when stressed, which researchers say could open up a new field of precision agriculture where farmers listen for water-starved crops.（已经记录下当植物有压力时它们发出的哭声的超声波，研究者们认为这开创了精准农业的一个新领域，农民可以听到缺水植物的声音。）”下文是说明这一研究的具体过程。文章是关于植物在受到缺水或者被砍断时的压力时，它们会发出声音。因此文章的标题应该是“植物在压力下会发出尖叫声”。故选D项。