EFFECTS OF C-6-C-10 ALKENALS AND ALKANALS ON ELICITING A DEFENSE RESPONSE IN THE DEVELOPING COTTON BOLL

In separate experiments, microbial-free compressed air carried individual C6, C-7, C-8, C-9, C-10-alkenals and alkanals into enclosed systems containing artificially wounded and non-wounded Acala SJ-2 developing cotton bolls. Two days after treatment, discs were excised from the treated cotton bolls surfaces and were extracted to determine the induction of the sesquiterpenoid naphthol phytoalexins, 2,7-dihydroxycadelene and 2-hydroxy-7-methoxy cadalene, their oxidation products lacinilene C and lacinilene C 7-methyl ether, and the coumarin phytoalexin scopoletin. Highest concentrations of the described phytoalexins were elicited by C6-C-10 alkenals in artificially wounded cotton bolls. C6-C-10 alkenals may function as volatile elicitors of a defence response in the cotton plant.