title: Cryopreservation of sugarcane using the V cryo-plate technique.
abstract: BACKGROUND
  Sugarcane is a tropical crop of major importance primarily for its high sucrose content. It is difficult to conserve it in the field or in vitro because of biotic and abiotic stresses. Cryopreservation of sugarcane germplasm is an appropriate approach for conserving its genetic diversity.
  
  
  OBJECTIVE
  This study was carried out to develop an efficient and practical cryopreservation protocol for sugarcane with high post-cryopreservation recovery.
  
  
  METHODS
  Factors affecting regrowth after cryopreservation using the V cryo-plate method including preculture medium, size of shoot tips, sucrose concentration in loading solution, exposure time to PVS2, light conditions after liquid nitrogen exposure, presence and absence of alginate gel and recovery medium composition were studied.
  
  
  RESULTS
  Shoot tips with a length of 1.5 to 2.0 mm, precultured on semi-solid 1/2 MS medium for 1 day and semi-solid MS medium with 0.5 M sucrose for 1 day, treated with LS containing 2.0 M glycerol + 1.6 M sucrose for 30 min and exposed to PVS2 for 30 min showed maximum (100%) recovery after cryopreservation. It was also observed that removing the alginate gel and keeping the cultures in the dark for 7 days after cryopreservation significantly improved recovery. After optimizing the cryopreservation conditions using sugarcane variety Ni-1, 10 additional varieties were cryopreserved using the optimized protocol, with regrowth ranging from 56.7% to 100%.
  
  
  CONCLUSIONS
  This study showed that V cryo-plate is an efficient and practical method for cryopreservation of sugarcane shoot tips in genebanks.
authors.forename: Tariq
authors.initials: T
authors.lastname: Rafique
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Fukui
authors.forename: Zahid
authors.initials: Z
authors.lastname: Mahmood
authors.forename: Takao
authors.initials: T
authors.lastname: Niino
mesh_terms: D015925:Cryopreservation / Q000295:instrumentation*; D003451:Cryoprotective Agents / Q000378:metabolism; D004867:Equipment Design; D018520:Plant Shoots / Q000254:growth & development*; D031786:Saccharum / Q000254:growth & development*; D013395:Sucrose / Q000378:metabolism; D058989:Vitrification
chemical_list: D003451:Cryoprotective Agents; D013395:Sucrose