Characterization of plant nematode genes: identifying
targets for a transgenic defence
C. J. LILLEY a1, P. E. URWIN a1andH. J. ATKINSON a1 a1 Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT,
Current control of plant parasitic nematodes often relies on highly toxic and environmentally harmful nematicides. As
their use becomes increasingly restricted there is an urgent need to develop crop varieties with resistance to nematodes.
The limitations surrounding conventional plant breeding ensure there is a clear opportunity for transgenic resistance to
lessen current dependence on chemical control. The increasing use of molecular biology techniques in the field of plant
nematology is now providing useful information for the design of novel defences to meet the new needs. Plant responses
to parasitism are being investigated at the molecular level and nematode gene products that could be targets for a direct
anti-nematode defence are being characterized. The potential of an anti-feedant approach to nematode control has been
demonstrated. It is based on the transgenic expression of proteinase inhibitors. The rational development of this strategy
involves characterization of nematode proteinase genes and optimization of inhibitors by protein engineering. Durability
of the resistance can be enhanced by stacking transgenes directed at different nematode targets.