Studies on Water Transport Through the Sweet Cherry Fruit Surface: IV. Regions of Preferential Uptake

Water uptake in different regions of the sweet cherry fruit ( Prunus avium L. cv. Sam) was investigated following selective application of silicone sealant to the pedicel end, pedicel cavity, pedicel/fruit juncture, or stylar scar of detached fruit. The time course of water uptake was monitored gravimetrically during a 3-hour incubation period in deionized water (20 °C). Sealing the pedicel end and/or pedicel/fruit juncture significantly reduced rates and total amount (3 hours) of water uptake, but sealing the stylar scar had no effect. The amount of water penetrating via the pedicel/fruit juncture increased between 50 and 85 days after full bloom. During the same period the maximum force required to detach pedicels from fruit (fruit removal force) fell from 5.2 ± 0.5 to 2.1 ± 0.2 N. The amount of water penetrating via the pedicel/fruit juncture and the fruit removal force were negatively related. Nuclear magnetic resonance (NMR) imaging of mature fruit incubated in D 2 O indicated that D 2 O accumulated in the pedicel cavity region and the pedicel. Our data suggest that the pedicel end and pedicel/fruit juncture, but not the stylar scar, are regions of preferential water uptake in detached fruit. Chemical name used: deuterium oxide (D 2 O).