問題詳情

請依下文回答第 36 題至第 38 題：The development of seawater agriculture has taken two directions. Some investigators have attempted to breed salttolerance into conventional crops, such as barley and wheat. For example, Emanuel Epstein’s research team at theUniversity of California at Davis showed as early as 1979 that strains of barley propagated for generations in the presenceof low levels of salt could produce small amounts of grain when irrigated by comparatively saltier seawater.Unfortunately, subsequent efforts to increase the salt tolerance of conventional crops through selective breeding andgenetic engineering─in which genes for salt tolerance were added directly to the plants─have not produced goodcandidates for seawater irrigation. The upper salinity limit for the long-term irrigation of even the most salt-tolerantcrops, such as the date palm, is still less than five part per 1,000(ppt)─less than 15 percent of the salt content of seawater.Normal seawater is 35 ppt salt.Our approach has been to domesticate wild, salt-tolerant plants, called halophytes, for use as food, forage, andoilseed crops. We reasoned that changing the basic physiology of a traditional crop plant from salt-sensitive tosalt-tolerant would be difficult and that it might be more feasible to domesticate a wild, salt-tolerant plant. After all, ourmodern crops started out as wild plants. Indeed, some halophytes─such as grain from the saltgrass Disticblis Palmeri─were eaten for generations by native peoples, including the Cocopah, who live where the Colorado River empties into theGulf of California.
【題組】36 Which of the following can be inferred from the passage?
(A)It is possible to domesticate a wild, salt-tolerant plant.
(B)It is feasible to add genes for salt tolerance to the plants.
(C)It is worthwhile to reduce the salt content of seawater from 35 ppt salt to 15 ppt salt.
(D)It is promising to change a traditional crop plant from salt-sensitive to salt-tolerant.

參考答案

答案：A
難度：適中0.46
統計：A(46),B(19),C(12),D(18),E(0)

用户評論

【用戶】雷慕莎

【年級】大二下

【評論內容】domesticate KK[dəˋmɛstə͵ket] 馴養（動物）；馴化

【用戶】糖衣

【年級】高二下

【評論內容】海水農業的發展採取了二個方向。 有些調查員試圖助長鹽容忍入常規莊稼，例如大麥和麥子。 例如， Emanuel Epstein的研究小組在加州大學在迪維斯表示早在1979年，為世代繁殖的大麥張力在鹽面前的低水平可能生產少量五穀，當由比較更鹹的海水時灌溉。 不幸地，隨後努力通過基因為鹽容忍增加直接地到plants─have沒被生產的好候選人為海水灌溉的有選擇性的飼養和基因engineering─in增加常規莊稼鹽容忍。 上部鹽分極限為長期灌溉最鹽寬容的莊稼，例如棗椰子，每1,000比海水鹽含量的15%仍然是較不比五部分(ppt) ─less。 正常海水是35 ppt鹽。 我們的方法將馴化野生，鹽寬容植物，稱鹽土植物，為使用作為食物、草料和油籽種子莊稼。 我們原因改變傳統...