3.3. Effect of dehydration on regeneration
To test the effect of dehydration on regeneration, precultured
shoot tips were dehydrated 25 ◦C on sterile dry silica-gel for dif-ferent intervals (0–15 h) or in laminar airflow for different lengths
of time (0–10 h) prior to directly immersion in LN. As showed in
Figs. 4–7, initial preculture of shoot tips resulted in a reduction in
the moisture contents to 72–74% following preculture on 0.75 M
sucrose for 2 days, No survival after rapid freezing was found with-out dehydration. Evaporative dehydration contributed to improve
the regeneration rate due to the reduction of moisture content.
The survival of cryopreserved shoot tips was detected when the
water content was lower than 24%. Regeneration rate of shoot
tips varied depending on the desiccation duration. The shoot tips
lost moisture rapidly with the increase of desiccation duration,