INVOLVEMENT OF ETHYLENE IN THE HARDCORE SYNDROME OF SWEET POTATO ROOTS

ABSTRACT Evidence presented supports our thesis that anethylene mediated reaction(s) functions in the series of events which lead to a market disorder of sweet potatoes called “hardcore.” Storage of roots in an environment conducive to ethylene accumulation or containing exogenous ethylene resulted in a higher incidence of hardcore. Alternatively, storage conditions designed to minimize endogenous ethylene accumulation decreased the extent of hardcore. Induction of hardcore was markedly reduced by carbon dioxide, a competitive inhibitor of ethylene mediated reactions. Sweet potato roots weighing less than 200g had a lower incidence of hardcore compared to larger roots. Also, low levels of ethylene gas were detected in the volatiles of sweet potato roots after long‐term chilling.