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Anther culture of the cytoplasm substitution lines
of Triticum aestivum cv. Chinese Spring
H. OGURA and K. TSUNEWAKI
Laboratory of Genetics Faculty of Agriculture, Kyoto Universtiy, Kyoto
606, Japan
Anthers of a common wheat, Chinese Spring and its cytoplasm substitution
lines with several Triticum and Aegilops cytoplasms were
cultured in vitro on the RM-1964 medium supplemented with 3 mg/l
of 2,4-D (LINSMAIER and SKOOG 1965). These wheat anthers containing pollen
grains at the uninucleate stage were further classified by microscopical
observation of the pollen grains into three sub-stages: the early, middle
and late uninucleate stages. They were incubated under continuous fluorescent
illumination of about 1,200 luxes and the constant temperature of 25C.
The pH of the medium was adjusted to 5.8+ or -0.1.
Callus formation was observed about 8 weeks after inoculation in the test
tubes, the results being presented in Table 1.
(Squarrosa)-Chinese Spring, (synthetic CCCUCU)-CS
(abbreviated as CS hereafter), (triuncialis)-CS, (variabilis)-CS,
(crassa 6x)-CS as well as normal Chinese Spring wheat formed no
calluses. On the other hand, (caudata)-CS, (umbellulata)-CS,
(timopheevi)-CS, (ovata)-CS and (kotschyi)-CS formed
calluses at 2.2, 0.8, 8.3, 6.7 and 1.1 % of the cultured anthers, respectively.
All the calluses formed were of filament and/or tapetum origin. Triticum
timopheevi and Aegilops ovata cytoplasms significantly increased
the frequency of callus formation, comparing to that of normal Chinese
Spring.
Frequency of the callus-forming anthers in these five lines were 5.9,
3.4 and 1.9%, when the pollen grains were at the early, middle and late
uninucleate stage, respectively. There is only one report in Triticeae
indicating that the pollen grains at the middle uninucleate stage were
most favorable for induction of calluses in the normal lines of wheat
(OUYANG et al. 1973). However, in the cytoplasm substitution lines
of Chinese Spring wheat, the anthers containing the pollen grains at the
early uninucleate stage tended to induce more calluses.
(Received July 25, 1974)
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