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 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 is 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.

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 discriminate 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 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 speculative（推测的）for now, she says.

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

A.tobacco plants make louder sounds than tomato plants when hurt

B.water-hungry tomato plants are more sensible than tobacco plants

C.unstressed plants produced sounds of laughter when being watered

D.plants respond to the sounds the plants make and protect themselves

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

A.Appreciative B.Doubtful

C.Cautious D.Optimistic

3.It can be learnt from the research that ________.

A.greenhouse effects can be avoided

B.soil condition can be adjusted in time.

C.plant condition can be diagnosed faster.

D.insects can be detected and removed easily.

4.What is the best title for the article?

A.Plants Get Stressed Just Like Us

B.Plants Scream in Presence of Stress

C.Sounds of Plants Detected Far Away

D.Sounds of Plants Break Farmers’ Hearts

Answer

1.B

2.C

3.C

4.B

【解析】

这是一篇说明文。文章讲述了，一项研究表明，植物在压力下会发出超声波叫声，这可能会开辟一个精确农业的新领域，让农民们倾听缺水作物的声音。

1.

细节理解题。由第四段中的“On average, drought-stressed tomato plants made 35 sounds an hour, while tobacco plants made 11.”（平均来说，干旱压力下的番茄植株每小时发出35个声音，而烟草植株每小时发出11个声音。），可知缺水番茄比烟草更敏感，干旱条件下，番茄植株发声多。故选B项。

2.

推理判断题。由倒数第二段“The suggestion that the sounds that drought-stressed plants make could be used in precision agriculture seems feasible if it is not too costly to set up the recording in a field situation”（干旱压力下植物发出的声音可以用于精准农业的建议，如果在田间条件下设置录音成本不太高的话，这一建议似乎是可行的。）和最后一段中的“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 speculative（推测的）for now, she says.”（她警告说，研究结果还不能扩大到其他压力，如盐或温度，因为这些可能不会导致声音。此外，她还说，目前还没有实验证明飞蛾或其他动物是否能听到并对植物发出的声音做出反应，所以这个想法目前仍然是推测性的。），可推断出Anne Visscher对实验的发现抱有谨慎的态度。故选C项。

3.

推理判断题。由第一段中的“But now, for the first time, they have been recorded making ultrasonic cries when stressed, which researchers say could open up a new field of precision agriculture where farmers listen for water-starved crops.”（但现在，有人首次记录到它们在压力下会发出超声波叫声，研究人员说，这可能会开辟一个精确农业的新领域，让农民们倾听缺水作物的声音。）和第五段中的“The researchers trained a machine-learning model to discriminate 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.”（研究人员训练了一个机器学习模型来区分植物的声音和温室里的风、雨和其他噪音，根据声音的强度和频率，在大多数情况下正确地识别出压力是由干燥还是割伤引起的。），可推断出此研究可以帮助人们更快地诊断出植物状况。故选C项。

4.

主旨大意题。由第一段中的“But now, for the first time, they have been recorded making ultrasonic cries when stressed, which researchers say could open up a new field of precision agriculture where farmers listen for water-starved crops.”（但现在，有人首次记录到它们在压力下会发出超声波叫声，研究人员说，这可能会开辟一个精确农业的新领域，让农民们倾听缺水作物的声音。）和第二段“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 is cut.”（以色列特拉维夫大学的伊扎克•哈伊特和他的同事们发现，番茄和烟草植物在缺水或茎被割下时发出的叫声频率是人类听不到的。），可知文章讲的是植物会在压力下发出人类听不到的超声波叫声，所以B选项“植物在压力下尖叫”，为短文最佳标题。故选B项。