Non-invasive photoacoustic spectroscopic determination of relative endogenous nitric oxide and ethylene content stoichiometry during the ripening of strawberries Fragaria anannasa (Duch.) and avocados Persea americana (Mill.)

Employing non-invasive photoacoustic spectrometry, emissions of nitric oxid e (NO) and ethylene in postharvest strawberries and avocados were monitored . A clear-cut stoichiometric relationship was found between the two gases: unripe fruit manifesting high NO and low ethylene levels-the converse in ri pe fruit. Findings are discussed in the light of putative control of ethyle ne-promoted fruit senescence by endogenous NO.