| Kiwifruits are difficult to storage for a long time at normal temperature after they had been harvested. And easy to losing green, softening and rotten during storage, transportation, sale and consumption of kiwifruit fruit,the attrition rate reaches as high as 20%~35%. Therefore, studing chlorophyll metabolism and physiological characteristics of kiwifruit pulp, seeking method and mechanism of keep fruit hardness and green, which not only provides theory basis and technology support for kiwifruit storage and transportation, but also provides reference for other green fruits and vegetables during storage and transportation.The paper researched that chlorophyll metabolism before and after"Qinmei"kiwifruit harvesting; Influence of different storing temperature on chlorophyll metabolism and physiological characteristics; Influence of different plant growth regulator 1-MCP, NO and 6-BA on chlorophyll metabolism, fruit quality, active oxygen metabolism and cell ultrastructure. The primary conclusions were as follows:1. During the growth after kiwifruit blossomed out from 70 days to 165 days, the content of chlorophyll a, chlorophyll b, carotinoid and chlorophyll increased; Activity of Chlorophyllase and Mg-dechelatase was opposite to chlorophyll content on change tendency; Fruit hardness decreased, soluble solids content and ratio of soluble solid content with titrable acid content increased. The titrable acid increased firstly and then droped; Respiration rate was topped when it blossomed out at 110 days; Ethylene release rate increased; superoxide radical content increased in fruit pulp and chloroplast; After blossom out from 70 days to 150 days, maloondiadehyde content, peroxidase and superoxide dismutase activity elevated in kiwifruit pulp and chloroplast; Blossom out from 150 days to 165 days, started to drop. Days of blooming date, ratio of soluble solid content with titrable acid content was the linear positive correlation with soluble solid content, relevant coefficient absolute value were 0.9747 and 0.9703 respectively; Soluble solid content, days of blooming date was the linear negative correlation with fruit firmness. Soluble solid content and ratio of soluble solid content with titrable acid content may decided harvest time of fruits.2. Kiwifruits were stored at 20℃±1℃, various pigments'content dropped rapidly, the speed of degrades was: chlorophyll b>chlorophyll a>carotinoid, fruit pulp turned quickly to yellow; Superoxide dismutase and peroxidase activity increased in pulp and chloroplast, superoxide radical content dropped, kiwifruits maintained freshness for 12 days.At 0℃±1℃stores, delayed senescence of kiwifruit, disintegration of cell wall and chloroplast in fruit pulp; Peroxidase with superoxide dismutase activity and superoxide radical content dropped in fruit pulp and chloroplast, the storage period was lengthened for 93 days than at 20℃±1℃storage.3. During the storage of kiwifruit at 0℃±1℃, 0.5μL·L-1,0.75μL·L-1 and 1.0μL·L-1 1-MCP treatment was extremely remarkable to suppress fruit hardness's dropping; During storing from 0 days to 60 days, it could delayed obviously the reduction of the content of pigments; 0.5μmol·L-1,1.0μmol·L-1 and 2.0μmol·L-1 NO treatment controlled softening of kiwifruit, but they were not obvious to delay pigment's degradation; all treatments were not remarkable to influence of SSC and titrable acid content.1.0μL·L-1 1-MCP treatment and 1.0μmol·L-1 NO treatment was the better concentration,they had the better result of keeping green and firmness。1μL·L-1 1-MCP and 1.0μmol·L-1 NO treatment could suppressed ethylene release rate, reduced hydrogen peroxide content; promoted the increasing of one hundred seeds weight, delayed the dropping of peroxidase activity of seeds. But 1μL·L-11-MCP treatment could better suppressed maloondiadehyde content accumulation than 1.0μmol·L-1NO treatment, it had suppressed fruit cell wall and chloroplast disintegration, postponed the time that peroxidase and superoxide dismutase active peak appears and fruit consenescence.MDA content and SOD activity of kiwifruit pulp was the linear negative correlation of contrast, 1.0μL·L-1 1-MCP and 1.0μmol·L-1 NO treatment fruit, relevant coefficient absolute value were 0.8679,0.8112 and 0.7201 respectively.4.During the storage at 0℃±1℃, the content of chlorophyll a, chlorophyll b, carotinoid, chlorophyll content and F0 value was decreasing of 1.0μL·L-1 1-MCP treatment,15mg·L-1 6-BA treatment, union treatment of 15mg·L-1 6-BA with 1.0μL·L-1 1-MCP and control treatment; Y value was elevated firstly then dropped; F0, Y value, L*, b* and a* only reflected approximate tendency of chlorophyll content and color change in kiwifruit pulp, they could not as correct index of color change of kiwifruit. Chlorophyllase and Mg-dechelatase were the the key enzyme. During the storage at 0℃±1℃, Fruit hardness and soluble solids content was the linear negative correlation, relevant coefficient absolute value was above 0.8800.Only considered from hardness, kiwifruit storing time of 1.0μL·L-1 1-MCP treatment, 15mg·L-1 6-BA with 1.0μL·L-1 1-MCP unite treatment and 1.0μmol·L-1 NO treatment was lengthened respectively for 75 days, 60 days and 30 days than contrast at 0℃±1℃storage. 1.0μL·L-11-MCP treatment had the better function of keeping hardness of kiwifruit. The better treatment of keeping green and firmness, the disintegration of cell wall and chloroplasts was slower, the fewer number of mitochondria. The structure of kiwifruit fruit's cell wall was compact in the initial period of storage. Chloroplast had massive big and clear starch granule. Along with the extension of stores time, the middle lamella disintegrated gradually, cell wall produced crevice, fruits changed to softening; Chloroplast changed from ellipse to roundness, chloroplast envelope breaked gradually; Chloroplast cavity turned to big, the chloroplast disintegrated gradually.The disassembly speed of fruit's cell wall and chloroplast with 1.0μL·L-11-MCP treatment was slowest and mitochondria number was few compared with control, Next was 15mg·L-16-BA with 1.0μL·L-11-MCP union treatment, only with 15 mg·L-16-BA treatment could not postpone the disassembly of fruit's cell wall and chloroplast.During storage at 0℃±1℃, 1.0μL·L-11-MCP treatment suppressed the respiration peak of kiwifruit, postponed the respiration peak appearance than control; very treatments reduced the ethylene release crest value than control. Activity of lipoxygenase increased gradually in fruit pulp and chloroplast of each treatments and contrast, superoxide radical content increased, hydrogen peroxide content reduced, maloondiadehyde content increased firstly then reduced; Activity of superoxide dismutase and peroxidase was declined of kiwifruit fruit;During storage period from 75 days to 150 days, fruit's peroxidase activity of 1.0μL·L-1 1-MCP treatment was higher than other treatments and contrast, proved that 1.0μL·L-1 1-MCP treatment was the better treatment to maintain freshness of kiwifruit.5. During the growth of kiwifruit, the cell wall structure turned to complete gradually and compactly, the chloroplast synthesized gradually, the starch granule gathered in the chloroplast envelope, the chloroplast is complete gradually, chloroplast's number increased gradually. Fruit pulp hardness and the chlorophyl content's change and the cell wall and the chloroplast ultrastructure's change has the direct relations.chlorophyll content and fruit hardness was the linear inverse correlation, it was the linear positive correlation that chlorophyll content with soluble solids content, titrable acid content, peroxidase and the superoxide dismutase activity, superoxide radical and maloondiadehyde content of fruit pulp and chloroplast; chlorophyll content was not correlation with Mg-dechelatase, pH value, respiration rate and ethylene release rate of fruit pulp. Chloroplast was one of main cell organs that it could producted superoxide radical.6. During the storage of kiwifruit at 0℃±1℃, the kiwifruit fruit's cell wall structure was compact in the initial storing period.There were massive big and the clear starch granule in the chloroplas. Along with the storing time extension, the middle lamella disintegrated gradually, the cell wall produced crevice, the fruit changed soften; The chloroplast changed from ellipse to circular, the capsule was broke gradually; The chloroplast cavity increased, the chloroplast disintegrated gradually. In the cell wall had the clear pit structure, along with cell wall's disintegration, the pit disintegrated gradually, the volume became small. it was the linear positive correlation that chlorophyll content with fruit hardness, superoxide dismutase activity and superoxide radical content in fruit pulp and chloroplast; Chlorophyll content was the linear positive correlation with peroxidase activity in fruit pulp; Chlorophyll content and soluble solids content was the linear inverse correlation; Chlorophyll content was not correlation with pH value, titrable acid content, respiration rate and ethylene release rate of fruit pulp. Chloroplast was also one of main cell organs that it could producted superoxide radical and hydrogen peroxide.7. During the growth and storage at 0℃±1℃of kiwifruit, it has respiration peak, ethylene release peak was late than respiration peak; Chlorophyll content and chlorophyll a, chlorophyll b and carotinoid content was the linear positive correlation. During the kiwifruit growth and storage, cell wall and chloroplast ultrastructure's observed result and fruit hardness and chlorophyll content's change result was tallies.
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