Physiological and Fresh-keeping Technological Study on Gladiolus and Gerbra Cut Flowers
|School||South China Normal University|
|Keywords||Gladiolus fresh cut flowers water balance quality physiology cold-store Gerbera neck-bent antioxidant chemical system|
Water metabolism and some physiological indexes of fresh cut Gladiolus flowers and cold stored cut Gladiolus flowers in vase and the effects of GA and 6-BA on the storage of cut Gladiolus flowers were investigated with purpose to discover the factor causing the quality degradation of cold-stored cut Gladiolus flowers and to provide theory basis for further researches on technology of keeping cut Gladiolus flower fresh. Mechanism of neck-bent of cut Gerbera flowers and antioxidant activities of 35 kinds of fresh flowers were also investigated in this paper when cut Gladiolus flowers were not available.The results showed that: water uptake of fresh cut Gladiolus flowers in vase dropped, change of fresh weight, water content and dry weight of florets in different site showed different trends; while changes of other physiological indexes of florets in different site showed a similar trend with soluble sugar content rose firstly then decreased, soluble protein content decreased, MDA content increased, activities of CAT and POD decreased, color of bracts become green firstly and then get yellow. Factors that affected the senescence of cut gladiolus flower and reasons why the top florets can not open were discussed.Effect of cold-storage on quality and some physiological indexes of Gladiolus cut flowers were investigated The result showed mat, compared with fresh Gladiolus cut flowers, water uptake of cold-stored Gladiolus cut flowers dropped remarkably; decrease of fresh weight shifted to an earlier date; maximum soluble sugar content of florets lowered; soluble protein content dropped; MDA content raised; activities of CAT and POD decreased and bracts of cut gladiolus flowers become yellow. Facts that caused the degradation of the quality of cut gladiolus flowers were discussed.The effects of 24h of 6-BA and GA (concentration: 50 u g · ml/1, 100 u g · mL-1 and 200 u g · raL"1) treatments on the quality of cold-stored cut Gladiolus flowers was studied in the paper. All the treatments improved the quality index after store(QIAS), raised the flower open rate (FOR), inhibited the degradation of chlorophyll, increased the contain of protein, lowered the contain of MDA.Among the treatment, 200 u g ml"1 GA was of the most efficiency. Water balance and some physiological indexes changes during vase life in cut Gerbera flowers, especially in the easy-bending sections of the scape, were investigated. The results showed that fresh weight and water content of cut gerbera flowers increased firstly but decreased afterwards; water absorption dropped; moisture loss caused by transpiration maintained at a stable level while water saturation deficit rose; that soluble protein content tended to decrease with the upper sections having a higher content than that in the middle and lower scape sections; that MDA content increased constantly; MDA content in the upper scape sections was lower when compared with that in the middle and lower sections; that no significant differences were detected in coarse fiber content between the middle and upper sections with the lower sections having a much higher content of coarse fiber; that POD activity varied slightly at earlier period but increased dramatically during the later period of vase life; POD activity in the upper sections was higher than that in the middle and lower sections. The causes of easy to bend neck in the middle section of the scape were discussed.Three vitro antioxidants screening systems, including lipoprotein PUFA peroxydation system induced by Fe2+, hemolysis system induced by H2O2 and ultraviolet-induced hemolysis system were adopted in this paper. Antioxidant activities of 35 kinds of fresh flowers were determined and compared. The results indicated that bud of 4 species of Rhododendron L. have the most efficient antioxidant activity in all sample.