Effect Of Bagging On Growth Characteristics,Quality And Storage Of Hayward Kiwifruit

In this paper,five-year-old Hayward Kiwifruit was used as materals,the experiment was done in Meixian kiwifruit experiment station of the Northwest A & F University from May 2009 to April 2010.A bagging experiment was conducted by using double paper bags,single paper bags(close and open of pocket bottom),plastic bags, and to not bagging as control.At the same time,using single paper bag bagged at 20d,30d,40d,50d,60d, after full bloom of Hayward kiwifruit . Effect on fruit growth,quality and storage of differernt bagging and different time bagging were researched, the main results as follows:1.In sunny days,the change curve of temperature in bags are just like mountain peaks.Within a single day,the temperature rise up sharply at 8:00, higher than 30℃at 10:00 and last 9 hours,the highest at 15:30, after 21:00 it is close to atmosphere,and the lowest at 6:00.The humidity inside bags has a negative correlation with temperature ,changing in"V"shape. In cloudy days,the temperature inside bags are higher than atmosphere about 0.5～1.5℃.In rainy days,the temperature inside bags are similar with outside,below at 30℃,the humidity more than 90%. After the rain, as temperatures rise, the outside humidity began to decrease, while the bags will keep moisture saturation longer period of time.2.The external quality of fruit has improved significantly after bagging.Fruit surface cleanliness of each treatment is higher than CK, especially in double paper bags the effect is best, I-class fruit more than 60%. Longitudinal diameter, Diameter and fruit weight of Plastic bags and double paper bags treatment are lager than CK,but the above index of single paper bags are lower than CK.The Chlorophyll content of double paper bags is minimum,and other treatment are lower than CK,it indiactes that low light environment has great influence on chlorophyll synthesis.3.The intrinsic quality of fruit has declined at different degrees after bagging.The fruit hardness of single paper bags is significantly lower than other treatment,and its soluble solids is higher than other treatment while harvest.Titratable acid content of double paper bags is highest.The total soluble sugar content of each treatment is lower than CK, especially the double paper bags only has 7.86mg/g, compared with CK declining about 4.9%.Dry matter content of the treatments is not significant.4. Fruit surface cleanliness become has gradually declined with the bagging time delayed,it is best in 20d bagging after full bloom, but the fruit size and weight were significantly lower than other treatments and CK. Fruit weight, total soluble sugar, starch and dry matter has gradually increased with the bagging time delayed, but still lower than CK, it shows that it is better to accumulate inclusions when bagging time is much later. It considerate that bagging at 40d ~ 50d after full bloom is the best choice.5.Storage life of each treatment has shortened comparing with CK at different degrees during room temperature storage.Respiratory peak of single paper bags appear at 18d,but CK at 24d,and other treatments in between. POD, amylase and PG activity of each treatment is high during early storage,but after the peak,enzyme activity of CK is higher than other treatments, and changes smoothly.