振动胁迫对杨梅果实采后衰老生理的影响

振动胁迫促进杨梅果实的衰老，表现为促进膜诱性的增加和ＳＯＤ活性与精胺含量的下降。但在振动胁迫后的贮藏初期，果实多源精胺的合成明显增加，而乙烯产生量明显降低，这可能是杨梅果实抗振动胁迫的一种应激机制。而在振动胁迫后的贮藏后期，果实的精胺含量降低，腐胺积累较多，乙烯产生量较高，表明振动胁迫最终促进果实的全面衰老。

Effects of Vibrational Stress on Postharvest Senescence Physiolgy of Chinese Bayberry Fruit

The effects of injury-free vibrational stress on polyamines content,ethylene production, superoxide dismutase (SOD) activity and membrane permeability of Chinese bayberry ( Myrica rubra Sieb and Zucc. ) during storage were investigated. The increase of membrane permeability and the decrease of SOD activity and spermine content were promoted by vibrational stress, showing that vibrational stress accelerated the senescence metabolism of Chinese bayberry. The synthesis of spermine increased whereas ethylene production decreased significantly during the intial post-vibration storage period, which demonstrated that a possible contingient mechanism of anti-vibrational stress existed in Chinese bayberry fruit. However, during the latter postvibration storage period, spermine content decreased while putrescine accumulated and ethyrene produced at a higher rate compared with the control fruit, showing that vibrational stress ultimately accelerated the overall senescence process of Chinese bayberry fruit.