Protocols for Micropropagation of Woody Trees and Fruits

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M. BERUTO AND P. CURIR
At this stage, new axillary buds arised (Figure 15D1,D2,E1,E2) and during spring
they developed into new branches with many new leaves. After dormancy in late
fall, plantlets started to bloom; the flower buds reached a complete development and
the flower production was true-to-type (Figure 15E1,E2).
3. CONCLUSIONS
Although tree peonies are not yet routinely micropropagated, the advances described
above could move us closer to that goal. In fact, the applicability of the described
micropropagation protocol has been tested for different genotypes, included the
dwarf types which are more difficult to in vitro propagate. Using buds with expanded
leaves as starting material for micropropagation was the key to successful establishment
and a plant propagation ratio between 2 and 5 per cycle was achieved
according to the genotype. Plantlets were rooted and successfully acclimatized under
in vivo conditions. So far, scanty reports are available about the in vivo performance
of the micropropagated tree peony plants. Our protocol provides in vitro shoots able
to flower after about 3 years and half from their establishment under in vivo conditions.
Taking into consideration that usually a 3 year old or older tree peony plant is
capable of blooming the season after planting, our results are approaching to a
commercial application. Further investigations will consider how to overcome the
difficulties related to multiplication decrease over the number of subcultures and to
provide quality assurance systems for the produced in vitro shoots.
Acknowledgements. The authors are grateful to Miss. C. Portogallo for her technical
assistance.
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