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.
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)

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