| As a typical berry, strawberry (Fragaria vesca L.) fruit is easily suffered from decay after harvest, which reduces its nutrient and commercial values. The effects of pre-temperature treatments on the storage of strawberry fruits were investigated in terms of fruits decay rate, selecting 'Feng Xiang' as research material. The quality properties and physiology and biochemistry index such as respiratory rate, enzymatic activities, endogenous hormones and the changes of protein in strawberry fruits with pre-temperature treatments were also studied in this paper. 1.The effects of pre-temperature treatments on the fresh preservation of strawberry fruits were studied. The results showed that the decay rate of fruit with pre-heat treatment under 50℃ for 30 min was the lowest whether storied at 5℃ or at room temperature. The decay rate of fruit with pre-cool treatment under 5℃ for 30 min was lower than the control fruit storied at room temperature. The pre-heat treatment had a better fresh preservation effect than the pre-cool treatment.2.The fruit quality could be improved because both pre-heat and pre-cool treatments could obviously inhibit the decrease of Vc content, soluble sugar and titrable acidity contents during the fruit storage at room temperature. The results of variance analysis showed that there was a significant difference between fruit qualities with pre-temperature treatment and those of control, and so was the ratio of sugar to acid between fruits with pre-temperature treatment and those of control. 3. Cellulase activity increased and the fruit firmness decreased gradually with the maturity of strawberry fruit. The results indicated that a significantly negative correlation existed between cellulase activity and the fruit firmness. The different pre-temperature treatments could remarkably inhibit the decrease of fruit firmness and the increase of cellulase activity during the fruit storage at room temperature, which could slow up the softness of strawberry fruit.4. SOD activity and MDA content in fruits increased gradually at the early stage of fruit storage. The pre-heat treatment could obviously increase SOD activity in fruits. SOD activity decreased and MDA content increased gradually at the later stage of fruit storage, but the pre-temperature treatment, especially the pre-heat treatment could obviously inhibit the decrease of SOD activity and the increase of MDA contents in fruits. POD and CAT activity could not be mensurated by titration means, UV absorbtion means and electrophoresis. 5. The respiratory rate of fruit increased gradually at the early stage of storage and speeded up suddenly at the later stage of storage. The pre-treatments before fruit storage could slow up the rising trend of respiratory rate in fruits.6. The changes of endogenous hormone content in fruits with different pre-treatments were studied. The results showed that ABA content accumulated and contents of ZR, IAA and GA descended during fruit storage. Both pre-treated and pre-cool treatments could obviously inhibit the increase of ABA content and the descending trends of contents of ZR, IAA and GA. In addition, there was a notably negative correlation between ABA and ZR, IAA, GA.7. The content of total soluble protein in fruits increased at early stage and then descended during the fruit storage. The contents of total soluble protein in fruits with pre-temperature treatments were less than those in control. In the later stage of fruit storage the contents of total soluble protein in fruit with pre-temperature treatments decreased slower than those in control. The protein components with molecular below 90 KD were analyzed by SDS-PAGE. The results showed that the content and the composition of protein in fruits increased significantly at the early stage of fruit storage, but decomposed at the later stage of fruit storage. The pre-temperature treatments, especially pre-heat treatment could inhibit the expression of enzymes concerned with the ripening and senescence of fruits(58.5KD,37.4KD,21.6KD and 17.1KD)...
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