Biochemical Mechanisms of Disease Resistance in Cotton: Applications to Breeding

A.A. Bell, M.E. Mace, and R.D. Stipanovic


 
ABSTRACT

The resistance of cotton to pathogens depends on a number of anatomical and chemical characters that both occur constitutively and are activated by attempted infection. We have concentrated on chemicals produced by cotton, that act as antibiotics or denaturants of extracellular proteins. The cotton plant produces a number of different antibiotic terpenoids in response to either bacterial or fungal infections. These compounds, called phytoalexins because they are formed in response to infection, include desoxyhemigossypol (desHG), hemigossypol (HG), hemigossypolone (HGQ), gossypol (G), and the methylated derivatives of each of these (desMHG, MHG, MHGQ, MG, and DMG). In addition, cells containing differentiated chloroplasts also synthesize terpenoid naphthols and naphthol ketones including 2,7-dihydroxycadalene (DHC), 2-hydroxy-7-methoxycadalene (HMC), lacinilene C (LC), and lacinilene C-methyl ether (LCM). The major constitutive antibiotics in cotton tissues are the condensed proanthocyanidins which are more commonly called tannins or condensed tannins. We have discussed evidence for the importance of these compounds in disease resistance in several reviews:



Reprinted from 1992 Proceedings Beltwide Cotton Conferences pg. 1337
©National Cotton Council, Memphis TN

[Main TOC] | [TOC] | [TOC by Section] | [Search] | [Help]
Previous Page [Previous] [Next] Next Page
 
Document last modified Sunday, Dec 6 1998