Rose Transformation and Regeneration
Genetic Study in Regenerative Ability
Optimization of Medium for Regeneration from Callus
A range of rose genotypes were evaluated for their propensity to regenerate
via somatic embryogenesis. Results indicated that there was a very strong
genetic component to this ability. This was confirmed by studying a
F1 progeny of the cross between a genotype which regenerates readily
via somatic embryogenesis and one that does not.
(Submitted for publication)
Tranformation of Rose with Green Fluorescent Protein
Somatic embryogenesis was initiated from in vitro-grown leaf explants
of rose using an induction period of 4 weeks on MS basal medium supplemented
with auxin followed by several subcultures on MS basal medium with cytokinin.
4th of July showed the highest regeneration frequency (24.4%)
on 5.3 uM NAA followed by culture on medium containing 18.2 uM zeatin.
Tournament of Roses produced somatic embryos when cultured
for 4 weeks on medium containing dicamba, 2.3 uM followed by three subcultures
on medium containing 18.2 uM zeatin. Embryogenic callus matured on MS
media containing 0.5 uM NAA, 6.8 uM zeatin, and 2.9 uM GA3. Long-term
cultures were established for both cultivars. Somatic embryos germinated
on MS medium containing IBA and BA. Silver nitrate (58.8 uM) enhanced
shoot formation and germination of somatic embryos.
Embryogenic calluses of Rosa hybrida cultivar 'Tineke' were transformed
with Agrobacterium tumefaciens strain LBA4404 containing the binary
vector pBIN m-gfp5-ER into which the virE/virG genes had been inserted.
Visualization of GFP-expressing cells enabled visual selection of dividing,
embryogenic cell clusters that were transgenic. When the Agrobacterium
strain with the bifunctional fusion maker containing additional virE/virG
genes was used, the number of green fluorescent calluses increased.