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Case Study 9.1 Engineered Salt Tolerance (Rehovot, Israel)
One area where agrobiotechnological advances could have distinctly environmental
applications, in the widest sense, is in the production of transgenic plants. While
much of this research has centred on greater productivity, some work has been done
to address other issues and one of the potentially most important of these relates to
improving salt tolerance.
According to some authorities, over half the world’s agricultural land is expected
to become increasingly saline within the next 50 years. In some countries, such as
Israel where this work was pioneered, fresh water supplies are already stretched to
the point that farmers are forced to use a proportion of salty water for irrigation and
it is anticipated that this usage will continue to grow in the future. If encroaching
desertification is to be avoided under these circumstances, then the development of
salt-resistant crops and trees becomes essential.
Researchers at the Hebrew University in Rehovot isolated the protein,BspA,
which is produced by the European aspen,Populus tremula, when growing in
salty conditions and appears to protect the tree’s cells from damage by attracting
water molecules, though the exact mechanism is still unknown. By introducing the
appropriate genes into other plant species, it is hoped that the varieties produced
may be afforded the same kind of protection.
Attempts to achieve this have been undertaken and the abilities of a related tree,
the Euphrates poplar,Populus euphratica, which is even more salt-tolerant are also
under investigation to see if it has other, additional methods which could likewise
be incorporated into future generations of transgenic crops. If this work proves
successful, it would herald a major breakthrough in mitigating a major cause of
global environmental degradation.