Phytoalexin Induction as a Factor in the Protection of Capsicum annuum L. Fruits Against Infection by Botrytis cinerea Pers.

Immature Capsicum annuum fruits treated at wound‐sites with glucans from the hyphal walls of Glomerella cingulata and incubated for 24 h or longer accumulated levels of capsicannol phytoalexins sufficient to inhibit rot development by Botrytis cinerea. Elicitor application to intact fruits induced the accumulation of relatively low levels of capsicannol compounds but further phytoalexin accumulation in fruits after wound‐inoculation with B. cinerea was much more rapid than in untreated fruits and rot development was suppressed. Capsicannol phytoalexins were produced in the live cells of the epidermis and little or no necrosis was associated with quantities produced in intact tissues. Elicitor treatment of intact fruits to protect against rot development by B. cinerea was achieved without the fruits sustaining unsightly damage.