| "GuiFei" mango was used to study the influences of exogenous GA3treatment with different concentrations before and after harvest on exterior and interior qualities of "GuiFer" mango’s. And the results were summarized as follows:(1)"Guifei" mango (80%maturity) was used to study, the effects of soaking treatment with different concentrations (0,0.1,0.3and1.0g/L) of GA3solution on post-harvest physiology and preservation quality. The results indicated that: compared with the control fruits, the treatment of GA3with different concentrationscan could inhibit the decrease in hardness and color change, dalay the changes in TSS, Vc and TA contents, and keep the storage quality of fruits, which is due to the increase in POD, SOD and CAT activities, inhibiting the increase of MDA content, and delaying the rise of pericarp cell membrane permeability. According to the preservation effect and exterior quality,0.5g/L GA3solution was the appropriate for mango fruits.(2)15-year-old "GuiFei" mango tree was used to study, the effects of pre-harvest spraying of GA3solution with different concentrations (0,0.5,1.0and2.0g/L) on quality and post-harvest physiology. The results showed that:compared with the control, the GA3treatment with0.5g/L and1.0g/L could inhibit the increase of fruit disease index, pericarp relative conductivity and MDA content, defay fruit TSS, VC and TA changes, maintain the storage quality of fruits. And when the fruit was fully ripening, the peel colour could change and pulp could soften normally. A high concentration of GA3(2.0g/L) treatment before harvest could significantly inhibit color and pericarp changes. At the end of the storage period (on30days), its chromaticity a*value (color transformed from green to yellow) was18.7lower than CK, there was significant difference among the treatments (p<0.01). These results suggested that GA3solution spraying before harvest with concentrations of0.5g/L and1.0g/L was useful to delay ripening and senescence of "GuiFei" mango, and improve storage quality.Although2.0g/L GA3could inhibit the colour change, it had an unexceptable influence on flavor quality.(3) The effects of GA3spraying treatment before harvest on accelerating ripening quality of "GuiFei" mango was investigated. The results demonstrated that: compared with the control, the GA3treatment with the dosages of0.5g/L and1.0g/L could delay the increase of MDA content in accelerated fruit and TSS, VC and TA contents changes, maintain the higher hardness, and make fruit normally change in color. However spraying GA3solution before harvest with high concentrations of2.0g/L would keep the higher TA content, and inhibit the color change, the flesh would still soften normally, and at the end of the storage period (on13days), its chromaticity a*value was lower23.28than CK, with significant difference among the treatment (p<0.01). These results suggested that spraying GA3solution before harvest with concentrations of0.5and1.0g/L could maintain the nutritional quality and flavor quality for accelerated fruits, while, when fruits treated by2.0g/L GA3before harvest, ethephone could not make the peel colour change, it had the bad effects on appearance and flavor quality of mango fruits.Therefore, for "GuiFei"mango, spraying GA3solution before harvest with concentrations of0.5g/L and1.0g/L could not only delay changes of storage quality, but also improve the flavor quality and nutritional quality of fruits treated by ethephone. In addition, soaking treatment after harvest with the concentration of0.5g/L GA3solution was appropriate to maintain appearance and flavor quality, and inhibit the ripening of "GuiFei" mango Fruits. |
