Changes Of Cell Wall Components And Cell Wall Degrading Enzyme Activity During Fruit Ripening Of Actinidia Arguta

Actinidia aruguta is widely distributed in China and has high value of exploitation and development,in recent years,artificially acclimated cultivated area of Actinidia aruguta has continuously increased,forming a new industry,however,the fruit ripening characteristics of Actinidia aruguta is not obvious,and it is difficult to accurately determine the maturity period,which limits the development of the industry.Conventional methods for judging maturation with soluble solids content have some limitations,in order to scientifically determine the fruit ripeness of Actinidia aru.guta,it is necessary to use a variety of indicators to make a comprehensive judgment.In this experiment,In this experiment,’ Huan you No.1’Actinidia aruguta as experimental materials,the fruit quality,cell wall composition,and cell wall degrading enzyme activity of Actinidia aruguta harvested at different harvesting stages were studied to comprehensively determine the optimal maturation period.The results showed that:(1)From the 20th day before the conventional harvesting period,the single fruit weight gain was smaller,and the fruit size did not change so much,which had no significant impact on the yield,the content of soluble solids in fruits showed an increasing trend,the titratable acid content increased and then decreased and showed a stable trend.From this stage,the quality and taste of the fruit were better.(2)From the change of cell wall composition during ripening of Actinidia aruguta,total pectin and hemicellulose were degraded on the 15th to 20th day before conventional harvesting date.Increased water-soluble pectin beginning 10 days before conventional harvesting,water-soluble pectin,acid-soluble pectin and alkali-soluble pectin all rapidly increased on the 5th day before the conventional harvesting date,and the cellulose content rapidly decreased on the 5th day before the conventional harvesting date,resulting in a gradual decrease in fruit firmness.(3)Study on Cell Wall Decomposition Enzymes in the Fruit Ripening of Actinidia aruguta,it was found that PG is the key enzyme in the ripening and softening process of Actinidia aruguta.In addition,PG began to function 20-15 days before the conventional harvesting period,β-Gal enzyme works later than PG enzyme.Cellulase reached the peak of activity on the 5th day before the day of conventional harvesting,which was consistent with the rapid decline of cellulose content.if Actinidia aruguta needs long-term transportation or storage,it should be harvested before the large amount of pectin and cellulose is degraded,that is,about 20 days before the conventional harvesting date;if long-distance transport or storage is not required,it should be conventional harvesting is harvested on the 5th of the previous day.(4)There was no direct relationship between flowering order and fruit ripening of Actinidia aruguta.The fruit quality,fruit cell wall composition and cell wall decomposing enzyme activity of Actinidia aruguta were determined to provide the basis for the best mature fruit of Actinidia aruguta.It is of great significance to grasp the best harvesting period of mature fruit of Actinidia aruguta.