The ethylenediaminetetraacetic acid (EDTA) method has been used to evaluate sucrose flux through pedicels. However, there was possibility that the sugar concentration in the exudate may decrease during its collection under cultivation conditions. To enable more accurate analysis of sugar translocation, sugar degradation during exudate collection must be inhibited. In this study, the EDTA method was modified by addition of 8-hydroxyquinoline hemisulfate salt hemihydrate (8-HQS) as an antibacterial agent to the EDTA solution and the effectiveness of the modified method was investigated. Exudates were collected from strawberry plants by the EDTA method with or without 200mg L−1 of 8-HQS. The exudates were stored under aerobic and anaerobic conditions in a refrigerator, or an incubator at 20℃ and 30℃. Though the concentrations of sugars in the exudates hardly changed in anaerobic conditions, the sucrose concentration in the exudates without 8-HQS decreased from about 1480 ppm to almost zero in a week and the glucose concentration increased in aerobic conditions. The rates of sucrose decrease and glucose increase were higher with increased storage temperature. However, the sucrose and glucose concentrations in the exudates with 8-HQS were unchanged during storage even under aerobic conditions. This indicated that the addition of 8-HQS to the EDTA solution inhibited sugar degradation in the exudate during its collection and allow more accurate analysis of translocation dynamics.

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