By Encapsulation - Dehydration Cryopreservation Kelp Female Male Gametophyte Of The Study

Gametophytes of Laminaria japonica Aresch(richang♀,richang♂)were cryopreserved in liquid nitrogen using encapsulation-dehydration. Gametophytes of female and male were encapsulated respectively in 3% Ca-alginate beads.Beads were desiccated with silica gel after pretreated in liquid medium containing sucrose,then directly immersed in liquid nitrogen.The cell viability after thawing was evaluated by gametophytes observation by fluorescence microscopy.The main factors influencing the viability,such as sucrose concentration,preculture time,dehydration rate,water content of beads,the capacity of gametophytes to reproduction.The results are as follows: 1. Effect of sucrose concentration and preculture time on viability of female and male gametophytes The effect of sucrose concentration on viability is more than the preculture time.Female and male gametophytes have various optimum preculture condition.The highest viability of female and male gametophytes are 45.9% and 29.7% after precultured for 9h in 0.4mol/L and 0.3mol/L sucrose solution respectively. 2. Effect of dehydration rate on viability of female and male gametophytes At different dehydration rate (a water reduction per hour 1%,5%,8%,10%,12%,15%,20%), female and male gametophytes obtained highest viabilities at the dehydration rate of 10% water content/h.Their highest viabilities are 49.8% and 34.6% respectively. 3. Effect of water content on viability of female and male gametophytes Water content of beads had more effects on viability after thawing than after dehydration.The optimum water contents of female and male gametophytes are 40%,the high viability reached 49.6% and 34.2% respectively. 4. the capacity of gametophytes to reproduction The female and male gametophytes which survived freezing showed that they had retained their reproductive capacity.The sporophytes formed from gametophytes after thawing are as same as the sporophytes formed from gametophytes after dehydration by observation by microscopy.