Carnation kamikaze

VIRUSES plaguing crops may soon meet their nemesis in what may be described as kamikaze genes residing in carnations. Martin Hartley of the University of Warwick has inserted into the tobacco plant a suicide gene taken from carnations to test its efficacy (New Scientist, Vol 141, No. 1994).

Hartley believes that if the suicide gene protects the tobacco plant against a virus, it may even come to the rescue of crops like tomato and potato.

The gene produces a com-pound that is harmless in plant cells until the cell is invaded by a virus. The virus sets off certain biochemical changes in the cell that turn the compound into a poison, killing both the infected cell and the unsuspecting virus.