Great difference of ethylene production was found among thesedifferent cultivars during cold storage (Fig. 3B). Ethylene produc-tion in ‘Gaixian’ and ‘Aozhou 14’ remained similar and increasedslowly with weak maximum values of 3.25 and 4.64 L kg−1h−1after 4 weeks of storage, respectively. In contrast, a rapid and dra-matic increase in ethylene production was detected in ‘Yuhuang’plums, reaching a maximum of 18.05 L kg−1h−1after 3 weeks ofstorage. Then the ethylene production of ‘Yuhuang’ increased again,reaching a second maximum of 5.78 L kg−1h−1after 7 weeks ofthe cold storage.