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Wheat Information Service
Number 93: 1-4 (2001)
Research article
Colchicine-induced chromosome doubling in wheat
haploids
R. 8. Sadasivaiah*, B. R. Orshinsky, S. M. Perkovic and B. L.
Beres
Agriculture and Agri-Food Canada, Lethbridge Research
Centre, PO Box 3000, Lethbridge, Alberta, Canada T1J 4B1
Summary
A large number (2,596) of wheat x maize hybridization-derived
haploids from 38 genotypes of soft white spring wheat were evaluated
for their response to colchicine treatment. Overall, 85.9% of the
treated plants survived treatment and 89.9% of these produced viable
seed, with a range of 46.7% to 100% among genotypes. The differential
response of genotypes to colchicine treatment was highly significant
(P<0.01).
Key words: wheat haploids, chromosome doubling, colchicine,
wheat x maize hybridization
Introduction
Haploid technology offers a useful breeding tool to enhance the
speed and efficiency of cultivar development (Baenziger et al. 1984).
However, the successful application of this technology to plant
breeding depends not only on reliable methods for the production of
haploids in large numbers, but also on al means of achieving a high
frequency of chromosome doubling to restore their fertility.
Two methods have been used to produce haploids in wheat:
anther/microspore culture and wheat x maize hybridization (Laurie and
Bennett 1986, 1988; Sadasivaiah et al. 1999). The use of anther
culture is limited by an overall low level of haploid production,
strong genotype, dependency and frequent albinism in regenerants
(Orshinsky and Sadasivaiah 1994; Lefebvre and Devaux 1996). The wheat
x maize hybridization technique, on the other hand, is less
genotype-dependent with no albinism; and the ease with which it can
be applied makes it more efficient than anther culture for the
production of haploids in common wheat (Sadasivaiah et al. 1999).
Although, the occurrence of spontaneous chromosome doubling in
anther-derived wheat haploids has been reported, it is generally an
infrequent and inconsistent event (De Buyser and Henry 1980; Metz et
al. 1988; Orshinsky and Sadasivaiah 1994; Mentewab and Sarrafi 1997;
Hansen and Andersen 1998). Furthermore, no such phenomenon has been
observed in wheat haploids derived from wheat x maize crosses
(Sadasivaiah et al. 1999). Therefore, there is the need for an
efficient technique for inducing a high level of chromosome doubling
in order to achieve the full potential of haploids in wheat breeding
programs.
A number of antimitotic/antimicrotubule agents have shown potential
for chromosome doubling in plants (Subrahmanyam and Kasha 1975;
Hansen et al. 1988; Hassawi and Liang 1991; Thomas et al. 1997;
Hansen and Andersen 1998; Hansen et al. 1998). Of these, colchicine
is the most widely used chemical agent for chromosome doubling.
In the present study, the wheat x maize hybridization technique was
used to produce haploids from a. diversity of genotypes used in our
soft white spring wheat breeding program. This paper reports on the
success rates of chromosome doubling in these haploids following a
colchicine treatment.
*Corresponding author: sadash@em.agr.ca
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