Water relation parameters of the cortex tissue of fresh 'fuji' apple fruit determined by centrifugation

This experiment was carried out to obtain a pressure-volume (P-V) curve and Holler diagram of the cortex tissue of fresh 'Fuji' apple fruit (Mains xdomestica Borkh.) with a novel centrifuge method. Based on the P-V curve and Holler diagram, several water relation parameters of cortex tissue were determined and the interrelationship of these parameters was established. Turgor loss point (TLP) occurred at -1.74 MPa and 73.7% of relative water content (R*). At full hydration, osmotic potential (psi(S)) was -1.30 MPa and symplastic water accounted for 86.8% of R*. Bulk elastic modulus decreased linearly by 28% as pressure potential declined from 1.30 MPa at full hydration to zero at the TLP. This centrifuge technique can provide a simple and efficient way to determine water relation parameters of fleshy fruits.