Canadian Forest Service Publications

Can explant choice help resolve recalcitrance problems in in vitro propagation, a problem still acute especially for adult conifers? 2017. Bonga, J.M. Trees 31:781–789.

Year: 2017

Available from: Atlantic Forestry Centre

Catalog ID: 38985

Language: English

CFS Availability: PDF (request by e-mail)

Available from the Journal's Web site.
DOI: 10.1007/s00468-016-1509-z

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For many conifer species, regeneration by organogenesis or somatic embryogenesis (SE) is still difficult and is often restricted to explants taken from juvenile donors. This review is based on the premise that there are tissues in the plant that are not normally used as explant, mostly because excising them in a viable state is difficult. Nevertheless, in cases where recalcitrance is a major problem, it may be worthwhile to pay closer attention to these tissues. Recalcitrance is a general problem, and discussion of it requires examples from the general literature. However, to restrict the scope of this review, preference will be given to conifer examples whenever possible.

Plain Language Summary

Clonal propagation of conifers by means of tissue culture has been very effective in improving the genetic quality of planting stock. The most effective procedure has been somatic embryogenesis (SE), by which hundreds of new plants are cloned from an embryo located inside a seed. This technology has found worldwide industrial application and has led to substantial increases in height and volume growth. One drawback of the SE technology is that currently it is restricted to cloning of embryos. Substantial additional benefits would be possible if cloning of selected, superior adult trees could be achieved. There are small tissue masses in various locations throughout the plant body that, by all expectations, could potentially serve as the initial source for cloning of adult trees. My review points out which tissues would qualify for that purpose. The review also explains that these tissues are difficult to access but that developing new technologies could make future profitable use of them more likely.

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