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phytoalexin

American  
[fahy-toh-uh-lek-sin] / ˌfaɪ toʊ əˈlɛk sɪn /

noun

Biochemistry.
  1. any of a class of plant compounds that accumulate at the site of invading microorganisms and confer resistance to disease.


phytoalexin British  
/ ˌfaɪtəʊəˈlɛksɪn /

noun

  1. botany any of a group of substances produced by plants that inhibit the growth of pathogenic fungi that infect them

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of phytoalexin

First recorded in 1945–50; phyto- + alexin