Abstract
Seeds obtained from kiwifruit (Actinidia deliciosa (A. chev.) C. F. Liang et A. R. Ferguson var. deliciosa cv. Hayward) were germinated and the calli derived from the hypocotyl of the seedlings were used to test various methods of cryopreservation. Some calli were found to be preserved after immersing in liquid nitrogen (LN) . The effective measures for preserving calli after immersing in LN are as follows ; calli were cultured with 24% (w/v) or 41% (w/v) sucrose for 2 days, and then after being dehydrated twice, first for 22 min with 60% (v/v) PVS2 (30% (w/v) glycerol, 15% (w/v) dimethyl sulfoxide, 15% (w/v) ethylene glycol and 13.7% (w/v) sucrose) and then for 23 min with 100% (v/v) PVS2, were preserved in LN. After cryopreservation, the calli were warmed in 37°C water immediately after being taken from the LN. They were washed in a liquid culture medium containing highly concentrated sucrose and then revived in a medium from which ammonium nitrate (NH4NO3) had been removed. These results will be important to the development of cryopreservation methods of kiwifruit germplasm.
