ARS | Publication request: Tracking Water Absorption in Split Susceptible Blueberries

Submitted to: HortScience
Publication Type: Abstract Only
Publication Acceptance Date: October 18, 2009
Publication Date: April 15, 2010
Citation: Marshall, D.A., Curry, K.J., Spiers, J.M. 2010. Tracking Water Absorption in Split Susceptible Blueberries. HortScience 45(4):496-497.

Technical Abstract: Rain related fruit splitting in blueberries has been a problem for commercial blueberry growers in the Southeastern US. The presence of split berries can cause an entire batch of berries to be rejected. Rejection of batches can be devastating to the growers and their income. Previous studies have shown that when rainwater is prevented from reaching the fruit directly, splitting still occurred indicating that some splitting is caused by water uptake by the roots alone, moving into the fruit via the vascular tissue of the berry. What is not known is if the cells within the berry are rupturing, or if the linkages between the cell walls are being compromised. The purpose of this study is to monitor the uptake of water into the berry to determine where the water is settling. A highly splitting susceptible ‘Pearl River’ pentaploid blueberry was selected for this evaluation. Whole, intact berries were immersed in acridine orange stain for 1,3, or 6 hours to monitor water uptake and location. Berries were hand sectioned, viewed and photographed with an Olympus BX60 microscope system equipped with fluorescence filters. Berry sections show dye absorption only into the berry vascular tissue occurring after 1 hour. After 3 hours the dye is found in tissue immediately surrounding the vascular bundles, and after 6 hours the dye is found in the cell walls throughout the berry. Water/dye is not found near the surface of the berry indicating that the water is being absorbed through the epidermis of the berry. Therefore, water absorption by blueberries occurs mainly through the vascular system of the berry and moves into the cell walls or the areas around the cell walls.