phytoalexin
/ˌfʌɪtəʊəˈlɛksɪn
/noun Botany
A substance that is produced by plant tissues in response to contact with a parasite and specifically inhibits the growth of that parasite.Plants produce phytoalexins as an immune response to physical, chemical, or biological damage....
- During infection by fungal pathogens, plant cells respond by expressing a battery of disease response genes, which can result in the production of various toxic plant products, including active oxygen species and phytoalexins.
- Plant resistance to specific pathogens is often correlated with increased production of phytoalexins, whereas inhibition or deficiency of phytoalexin production allows greater virulence.
Origin
1940s: from phyto- 'of plants' + alexin, a name for a class of substances found in blood serum, able to destroy bacteria.