| The 'Roberson' navel orange were used in the study on storage of fruits kept on the tree. Firstly, the tree crown of navel orange was consperged using Ca (NO3)2 and different concentration combination of GA3 and 2, 4-D solution. Secondly, the body of tree was coverd with plastic membrane. Finally, the fruit were bagged using different fruit bags. The main results of this research are showed as follows(1) The 'Roberson' navel orange were treated using different concentration combination of GA3 and 2, 4-D solution. The effect of two kinds of plant growth regulator to suppress shedding of fruit was observed and counted. The results were indicated that the effect of treatments of 20mg/L GA3+20mg/L 2, 4-D and 50mg/L GA3+20mg/L 2, 4-D solution were optimal to suppress shedding of navel orange fruit.(2) Two kinds of combination (20mg/L GA3+20mg/L 2, 4-D and 50mg/L GA3+ 20mg/L 2, 4-D solution) whose effect was optimal were selected to use in the experiment of storage of fruits kept on the tree, combined with 1000mg/L Ca(NO3)2, bagging and cover of plastic membrane. 12 treatments were established in this study. All the treatments were performed three times. The results of this experiment are showed as follows: the quality of fruit kept on tree was obviously higher than tradition storage.(3) Two treatment(20mg/L GA3+20mg/L 2, 4-D and 50mg/L GA3+20mg/L 2, 4-D solution) effect of suppressing fruit shedding and edible quality of fruit was same, but the treatment(50mg/L GA3+20mg/L 2, 4-D)which made fruit color light could influent appearance of fruit.(4) The fruits which were treated using double-deck bag and cover of plastic membrane were easy to infect diseases, insect pests and fruit shedding, comparing to olny covering plastic membrane. The fruit were treated using double-deck bag, Its colour of peel is light. If the fruit were treated using double-deck bag and 50mg/L GA3, Its colour of peel is lighter. (5) The effect that the tree were consperged using Ca(NO3)2 solution was more notable than that the tree were not consperged using Ca(NO3)2 solution in the same condition, it displayed the fruit were more deep. It indicated supplying Ca2+ could promote fruit colouration during fruit kept on tree.(6) The results were aggregately analysis. The optimal protocol of navel orange fruit storage kept on tree was: 20mg/L GA3+20mg/L 2, 4-D + 1000 mg/L Ca (NO3)2 solution treatment and cover of plastic membrane in the warm winter. If the air temperature of winter was below 0℃, the fruit should be bagged to prevent hypothermal injury. The navel orange storage fruits kept on the tree could brought more profie than storage fruits under normal temperature, the rate of added profie is around 40%. |
