Gossypol, cotton plant structure

Another compound bordering between preformed and induced defenses is gossypol. This compound accumulates within epidermal glands on the surface of cotton plants and is very toxic to some insects [ .]. Gossypol, and a series of structurally related compounds on the same biosynthetic pathway, accumulate to substantially increased levels in plants that have been challenged by potential pathogens. For this reason they have been considered phytoalexins by some plant pathologists. Phytoalexins are inducible antibiotics and will be discussed later. 

Gossypol from the cotton plant Gossypium herbaceum (Malvaceae) is a sesquiterpene dimer, in which the isoprene units are arranged into two bonded aromatic structures. 

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