Cryopreservation Of Gametophytes Of Undaria Pinnatifida By Encapsulation-dehydration

This　test　studied　the　cryopreservation　and　usual　preservation　of　gametophytes　of　Undaria　pinnatifida.　gametophytes　of　Undaria　pinnatifida.　Were　encapsulated　in　3%　calcium　alginate　beads.　In　the　cryopreservation,　the　main　factors　influencing　the　viability　and　the　development　ability　of　gametophytes,　such　as　sucrose　concentration,　preculture　time,　dehydration　rate,　water　content　of　beads　and　thawing　rate　were　studied.　In　the　usual　preservation,　we　studied　the　different　temperature,　water　content　and　light　that　influenced　the　viability　of　gametophytes　of　Undaria　pinnatifida.　The　results　of　cryopreservation　are　as　follows:　1.　Effect　of　sucrose　concentration　and　preculture　time　　The　alginate　beads　were　precultured　in　the　medium　containing　different　sucrose　concentration　(0.2,0.3,0.4,0.5mol/L)　for　different　time　(3,6,9,12h).　The　preculture　of　sucrose　had　more　effects　on　cell　viability;　the　high　viability　can　be　obtained　when　alginate　beads　were　precultured　for　9h　in　the　medium　containing　0.3mol/l　sucrose.　2.　　Effect　of　average　dehydration　rate　　At　different　average　dehydration　rate　(a　water　reduction　per　hour　1%,　2.5%,　5%,　8%,　10%,　15%,　25%),　gametophytes　obtained　the　hightest　viability　at　the　dehydration　rate　of　5%　water　content/h.　3.　Effect　of　water　content　　At　an　average　dehydration　rate　of　5%　water　content/h,　water　contents　in　beads　were　15%,　25%,　35%,　45%,　55%,　65%,　85%　respectively.　The　highest　viability　was　obtained　when　the　alginate　beads　were　dehydrated　to　25%　water　content.　4.　　Effect　of　thawing　temperature　The　temperature　of　thawing　has　more　effects　on　cell　viability.　The　study　indicated　that　the　viability　was　improved　with　the　thawing　temperature　increased　　when　　thawed　in　cryotubes.When　thawed　in　liquid　,the　temperature　reached　　25℃,　the　viability　was　the　highest　.　Under　optimum　conditions,　the　cryopreservation　viability　of　gametophytes　can　reach　73%　at　most;　after　cryopreservation,　the　gametophytes　can　produce　the　normal　sporophytes　in　the　conditions　suitable　for　development.　The　results　of　usual　preservation　are　as　follows:　The　viability　of　gametophytes　of　Undaria　pinnatifida　has　significant　difference　at　different　temperature　and　water　content　.We　can　obtain　the　highest　viability　when　the　water　content　of　alginate　beads　is　50%　at　4℃.　After　180d　kept　in　LN,　the　viability　of　gametophytes　was　still　over　90%.