Scientists from The University of Edinburgh have discovered a gene that
could help develop disease-resistant crops. The scientists studied how
plants produce nitric oxide when they are under attack from bacteria or
viruses. Nitric oxide accumulates in plant cells and triggers a response
from the plant's immune system.

The research team used Arabidopsis to study the genes that were triggered as
nitric oxide levels rose. They found that a previously unknown gene - called
SRG1 - is rapidly activated by nitric oxide and is also triggered during
bacterial infection. Further studies showed that SRG1 activates the plant's
defense mechanism by limiting the activity of genes that suppress the immune
response. They also found that nitric oxide regulates immune response, which
ensures that the plant's defense system does not over-react.

[www.ed.ac.uk]
ps