Immature embryos of 10 accessions of Triticum tauschii,
the D genome donor of Triticum aestivum, were used to
produce embryogenic callus for the initiation of suspension cultures. For the
long-term maintenance of embryogenicity of these suspensions, it was necessary
to use different media for the initiation, establishment and maintenance
phases. The initiation phase required media supplemented with L-proline,
L-asparagine and L-glutamine, together with Dicamba at 12 mg L
−1 and maltose. In the establishment phase, it was
essential to reduce the concentration of Dicamba to 6 mg L
−1 for the rapid production of fine suspension
cultures. Finally, the long-term maintenance of a capacity for regeneration
depended on the inclusion of 1.1 mg L −1
2,4-dichlorophenoxyacetic acid and 30 g L −1
sucrose in the medium. By the use of these procedures, long-term embryogenic
fine suspension cultures were established from two accessions, while
non-embryogenic fine suspension cultures were produced from five accessions.
Over 90% of plants regenerated from fine suspensions of 1-year-old
embryogenic cultures were fertile, and embryogenic suspension cultures
retained their regeneration capacity for more than 3 years.
Genetic and Physiological Architecture of Early Vigor in Aegilops tauschii, the D-Genome Donor of Hexaploid Wheat. A Quantitative Trait Loci Analysis