“Salty” RicePlant Boosts Harvests

British scientistsare breeding a new generation of rice plants that will be able to grow in soilcontaining salt water.Their work may enable abandoned farms to become

productive oncemore.

Tim Flowers and TonyYeo,from Sussex University'sSchool of Biological Sciences,have spent severalyears researching how crops,such as rice,could be made to grow in

water that hasbecome salty.

The pair haverecently begun a three-year programme,funded by the Biotechnology andBiological Sciences Research Council,to establish which genes enable someplants to

survive saltyconditions.The aim is to breed this capability into crops,starting with rice.

It is estimated thateach year more than 10m hectares（公顷）of agricultural land are lost because salt gets into the soil andstunts（妨碍生长）plants.The problem is

caused by severalfactors.In the tropics , mangroves（红树林）that create swamps（沼泽）and traditionallyformed barriers to sea water have been cut down .In the

Mediterranean,aseries of droughts have caused the water table to drop,allowing sea water toseep（渗透）in.In LatinAmerica , irrigation often causes problems when water

is evaporated（蒸发）by the heat , leaving salt depositsbehind.

Excess salt thenenters the plants and prevents them functioning normally.Heavy concentrationsof minerals in the plants stop them drawing up the water they need to survive.

To overcome theseproblems,Flowers and Yeo decided to breed rice plants that take in very littlesalt and store what they do absorb in cells that do not affect the plants'

growth.They havestarted to breed these characteristics into a new rice crop,but it will takeabout eight harvests before the resulting seeds are ready to be considered for

commercial use.

Once thecharacteristics for surviving salty soil are known,Flowers and Yeo will try tobreed the appropriate genes into all manners of crops and plants.Land that hasbeen

abandoned to na-ture will then be able to bloom again,providing much needed food in the poorercountries of the world.

Flowers and Yeohave started a program______.

A.to find ways toprevent water pollution

B.to identify genesthat promote growth in salty soil

C.to breed riceplants that taste salty

D.to find ways toremove excessive salt from soil