AbstractThe factors that affect gum formation in stone‐fruit trees share the common feature of stimulating ethylene production in plant tissues. It is suggested that ethylene might play an important role in gummosis. The chemical structure of the exudate gums is similar to that of certain cell‐wall polysaccharides and it is possible that gummosis is caused by excessive formation of these polysaccharides as a result of ethylene production in the tiss