Protocols for Micropropagation of Woody Trees and Fruits

MICROPROPAGATION OF MATURE TREES 245
subsequent subcultures. Approximately 75% of U. glabra, U. minor and U. laevis
cultures regenerated after 12 months of cold storage without subculture.
2.9. Statistical Analyses
One-way analysis of variance (ANOVA) was used for the statistical evaluation of the
results.
3. CONCLUSION
This protocol describes an efficient method for in vitro micropropagation of elms,
important European native trees. To date, 8-year-old in vitro-propagated trees (Figure
4B) do not show abnormal morphological variation or growth characteristics in
comparison with generative-propagated trees. We focused also on studying the
possibility to increase the elm explant multiplication rate by cutting the regenerated
shoots to apical and basal parts. Our attempt was to establish a relationship between
endogenous hormonal content and in vitro morphogenic responses of elm explants.
The shoot forming capacity was higher in the apical part but the timing of root
formation was in this type of explant significantly delayed (compared with the
organogenic potential of basal part). We have shown that the efficiency of our elm
multiplication system in terms of shoot multiplication and rate of root initiation was
significantly influenced by the endogenous levels of auxin, cytokinins (predominately
zeatin and dihydrozeatin), polyamines and phenolic acids in the explants (Mala
et al., 2006). Our results demonstrate that this protocol can be used routinely for
multiplication of elms.
4. REFERENCES
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