Genetic, Epigenetic and Morphological Evaluation of the Effects of Cryopreservation on Papaya

View/ Open
Author(s)
Primary Supervisor
Drew, Rod
Ashmore, Sarah
Other Supervisors
Panis, Jozefus
Year published
2010
Metadata
Show full item recordAbstract
A vitrification-based cryopreservation technique for storage of in vitro shoot tips of papaya has been tested to ensure applicability across a range of genotypes and to assess the stability of both genotype and phenotype of clonal material following cryopreservation. Shoot tips of twelve female genotypes were cryopreserved, regeneration percentages were determined and resultant plants were screened for genetic and epigenetic changes. Genomic DNA structure was studied using polymerase chain reaction (PCR) based randomly amplified DNA fingerprinting (RAF), and methylation patterns were monitored using the amplified ...
View more >A vitrification-based cryopreservation technique for storage of in vitro shoot tips of papaya has been tested to ensure applicability across a range of genotypes and to assess the stability of both genotype and phenotype of clonal material following cryopreservation. Shoot tips of twelve female genotypes were cryopreserved, regeneration percentages were determined and resultant plants were screened for genetic and epigenetic changes. Genomic DNA structure was studied using polymerase chain reaction (PCR) based randomly amplified DNA fingerprinting (RAF), and methylation patterns were monitored using the amplified DNA methylation polymorphism (AMP) PCR technique. Plantlets were regenerated following cryopreservation in all but one genotype and regeneration percentages of 61-73% were obtained from 6 genotypes. The regenerated plantlets showed varying levels of genomic DNA modifications (0-10.07%), and methylation modifications (0.52-6.62%) for detected markers. These findings have not been reported previously for papaya, and indicate some genotype dependent variability in DNA modifications occurred following cryopreservation which could result in somaclonal variation.
View less >
View more >A vitrification-based cryopreservation technique for storage of in vitro shoot tips of papaya has been tested to ensure applicability across a range of genotypes and to assess the stability of both genotype and phenotype of clonal material following cryopreservation. Shoot tips of twelve female genotypes were cryopreserved, regeneration percentages were determined and resultant plants were screened for genetic and epigenetic changes. Genomic DNA structure was studied using polymerase chain reaction (PCR) based randomly amplified DNA fingerprinting (RAF), and methylation patterns were monitored using the amplified DNA methylation polymorphism (AMP) PCR technique. Plantlets were regenerated following cryopreservation in all but one genotype and regeneration percentages of 61-73% were obtained from 6 genotypes. The regenerated plantlets showed varying levels of genomic DNA modifications (0-10.07%), and methylation modifications (0.52-6.62%) for detected markers. These findings have not been reported previously for papaya, and indicate some genotype dependent variability in DNA modifications occurred following cryopreservation which could result in somaclonal variation.
View less >
Thesis Type
Thesis (PhD Doctorate)
Degree Program
Doctor of Philosophy (PhD)
School
School of Biomolecular and Physical Sciences
Copyright Statement
The author owns the copyright in this thesis, unless stated otherwise.
Item Access Status
Public
Subject
Cryopreservation
Papaya cells
Cryopreservation of papaya shoot tips