| Changes in cell water relations during precultures were followed in an attempt to understand the mechanism of cell hardening for cryopreservation by vitrification. Medium containing 0.4 M sucrose (psiw=-1.45 MPa) and containing 5 mg L-1 of ABA (MT psiw=-0.73 MPa and MS psiw=-0.48 MPa) were used to harden cell suspensions of orange and carrot. Preculture in these medium did not cause a significant decrease of cell viability, however, it improved the cell survival to PVS2 and liquid nitrogen expositions. When cells were inoculated into medium containing 0.4 M sucrose, the cell psiw decreased rapidly until reach the medium psiw , and turgor was also severely reduced or disappeared. Subsequently, cell psis began to decrease and after 48 h of treatment in low... |
