英文摘要 |
To study the effect of pre-harvest water management on the losses of ‘Ponkan’ mandarin, mulching treatments were conducted together with five timing suspension irrigation treatments. In these treatments, supplemental irrigation was executed and suspended at 56, 28, 14, 7 and 3 days prior to harvest. In the control treatment, trees were grown only under rain fed conditions without any irrigation supply. After 3 days prestorage curing, the decay percentage of the largest fruit (>27cm) was more than the size of the treatments of withholding water for less than 7 days prior to harvest. After fruit storage for one month, the treatment of withholding water supply 56 days prior to harvest produced more decay percentage in large (>27cm) and medium (27cm-25cm) size fruits than in the small ones. The green button percentage of large and medium size fruits decreased gradually with the advancement of the storage period and the decreasing trend was influenced significantly by different treatments. At the first month of storage, an increase in peel puffiness was observed in all the treatments, but the increased rate slowed down in the next month. The small size fruit harvested from the trees withholding water supply 56 days prior to harvest showed higher titratable acidity than those picked from the trees withholding water supply 14 days prior to harvest for three month. In addition, the medium size and large size fruits from all the groups stopping the supply of water too close to harvesting showed the same titratable acidity compared with fruits treated with withholding water for 14 days before harvesting. |