RNGR.net is sponsored by the USDA Forest Service and Southern Regional Extension Forestry and is a colloborative effort between these two agencies.

U.S. Department of Agriculture USDA Forest Service Southern Regional Extension Forestry Southern Regional Extension Forestry

Skip to content. | Skip to navigation

Home Publications Forest Nursery Notes 2009 Winter Forest Nursery Notes 2009 Winter Forest Nursery Notes - New Nursery Literature Cryptic Genetic Bottlenecks During Restoration of an Endangered Tropical Conifer

Cryptic Genetic Bottlenecks During Restoration of an Endangered Tropical Conifer

Kettle, C. J., Ennos, R. A., Jaffre, T., Gardner, M., and Hollingsworth, P. M. Biological Conservation 141:1953-1961. 2008.

Forest restoration programmes aim to use material for re-planting that is genetically diverse and not inbred. However, restricted seed sampling, high variance in reproductive output, and the production of inbred seeds that survive in the nursery but not in the wild can lead to forest restoration stock being genetically compromised. The aim of this study was to evaluate whether the reproductive biology of the New Caledonian endemic conifer Araucaria nemorosa makes it susceptible to these genetic problems and to assess whether there is evidence for genetic bottlenecks and elevated inbreeding in nursery stock compared to seedlings and adults from wild source populations. Reproductive output was low with high variance among trees (only 14% of adult trees surveyed produced mature cones, >50% of examined cones had <10 viable seeds). Evidence for an extreme genetic bottleneck was detected in a nursery population established from cones collected from adult trees. A second nursery population established with seed collected from the forest floor showed no evidence of a genetic bottleneck, but was inbred compared to its wild source population. In light of these results, we do not recommend collecting cones directly from A. nemorosa as an efficient means of establishing genetically diverse stock for restoration programmes. Collecting seed from the forest floor is likely to be more effective, but the planting stock may contain a high proportion of inbred individuals. Collecting established wild seedlings already subjected to natural selection is suggested as an alternative method of maximising the diversity captured, whilst minimising sampling effort and proportion of inbred individuals.


Download this file:

PDF document Download this file — PDF document, 103Kb

Details

Author(s): C. J. Kettle, R. A. Ennos, T. Jaffre, M. Gardner, P. M. Hollingsworth

Section: Tropical Forestry and Agroforestry

* This publication is copyrighted.