The induction, in vitro, of chromosomal variation in rosa

The culture in vitro was investigated in 7 clones of roses
representing a range of genotypes and ploidy levels. Particular
attention was paid to a sterile hybrid, R.persica x xanthina , from
which it was hoped to obtain tetraploid clones. It was anticipated
that tetraploid clones might be fertile and that this would facilitate
introgressive hybridization of R.persica genes into various classes
of cultivated roses. Propagation medium was developed based on MS
salts and vitamins supplemented with BAP and NAA. Doubling times of
2-4 weeks were obtained on optimum media.
Transplantation to soil was achieved with
R.wichuraiana had a 99% success rate _____
conditions when a misting system was used whereas transplantation with
R.ruRpsa 'Scabrosa' was only 46% successful and no success was achieved
with R.persica x xanthina . Success rates were subsequently improved
R.persica
varying degrees of success,
on transfer to in vivo
to 80% with 'Scabrosa' and
Sorbarod plugs prior to transplantation.
Whilst in culture adventitious shoots were induced
clones ( R.laevigata , R.wichuraiana and R.persica
R.persica
shoots
x xanthina by the use of
from leaves of 3
x xanthina ) but
only with
adventitious
callus.
The cell
established _____
procedure. This was
exposure to colchicine
gave
x xanthina
from
_____ did it prove possible to induce
internodal stem segments, roots, leaves and
the cycle time of
in vitro as 10.25 hours
used in discussing
diploid rose R.wichuraiana was
using an autoradiographic
the optimal duration of
solution. It was
complete spindle inhibition without a
found that
reduction
0.05% colchicine
mitotic index. in
The addition of DMSO was shown to aid the uptake of colchicine into
shoot meristems. Terminal buds of R.wichuraiana and R.persica x
xanthina were exposed
level
to colchicine solution in
plants derived from these buds was
and measuring length of stomata
vitro and the
determined by ploidy of
karyotyping of root cells (LIII layer)
(LI layer).
X-irradiation was used in vitro to obtain different morphological
forms, dose rates of 3, 4 and 5 krads producing 68, 100 and 80% mutant
forms respectively. It is suggested that the combined use of drug and
X-ray treatments, use of GA^ and protoplast fusion in vitro would be
appropriate subjects for further investigation.

This thesis supplied via ROAR to UEL-registered users is protected by copyright and other intellectual property rights, and duplication of any part of the material is not permitted, except for your personal use for the purposes of non-commercial research and private study in electronic or print form. You must obtain permission from the copyright-holder for any other use. Electronic or print copies may not be offered, for sale or otherwise, to anyone. No quotation from the thesis may be published without proper acknowledgement.