INTERNATIONAL PROVENANCE TRIALS OF PINUS CARIBAEA VAR. BAHAMENSIS ¹

by

W.B.H. Baylis and R.D. Barnes
Oxford Forestry Institute, Department of Plant Sciences
University of Oxford, South Parks Road
Oxford OX1 3RB, U.K.

Pinus caribaea var. bahamensis occurs naturally only on four islands of the Bahamas, viz. Andros, Abaco, Grand Bahama and New Providence and on North and Middle (Grand) Caicos islands. Interest arose in P. caribaea in the 1960s when its potential for softwood plantation development in tropical countries was recognized. International provenance trials, funded primarily through Research Schemes of the Overseas Development Administration of the United Kingdom (ODA), with contributions from Commonwealth countries and FAO, were coordinated by the Oxford Forestry Institute (OFI). A large number of seed sources of P. caribaea var. hondurensis was tested in these trials. P. caribaea var. bahamensis was, however, inadequately sampled across its natural range. Despite its excellent stem and branch form and good growth, interest in this latter species has always been overshadowed by P. caribaea var. hondurensis which generally out-performs it in growth, except in a narrow range of environments where conditions are too temperate for P. caribaea var. hondurensis and too tropical for P. elliottii. Recently, however, it has become evident that P. caribaea var. bahamensis (and var. caribaea from Cuba) is virtually immune to the pine shoot moth (Rhyaciona and Dioryctria spp.) attack that has devastated P. caribaea var. hondurensis plantations in south-east Asia. P. caribaea var. bahamensis has therefore suddenly assumed much greater potential over a huge area because, together with P. caribaea var. caribaea, it is the next most productive softwood after P. caribaea var. hondurensis. If the shoot moth were to spread further, these two varieties could take over as the most important tropical softwoods at low latitudes and low altitudes.

In June, 1986, FAO in collaboration with the Government of the Bahamas, executed a study of forest genetics and seed production of P. caribaea var. bahamensis in the Bahamas (Barnes, 1986). As a result of this project, the establishment of new international provenance trials of the species was recommended. A strategy for collection of seed for the trial was designed that would provide genetic information of use to the Bahamas in developing their resource, as well as being useful to developing countries in acquiring seed to improve the productivity of their plantations.

In June 1988, ODA funded a six-month project for the OFI, in cooperation with the Department of Lands and Surveys of the Bahamas, to collect the seed recommended in the 1986 FAO report ². The resultant collections are listed in the attached table. In the event, collection of seed from the Turks and Caicos Islands proved logistically impracticable in the same year but seed trees were selected. It is hoped that it will be possible to collect from them later.

All seed is held, stored and tested by the OFI. It is now ready for distribution. There will be four objectives in using this material:

1. to study between-provenance variation in provenance trials, using bulked seed;
2. to study within-provenance variation in progeny/provenance trials, using separate half-sib families;
3. to establish conservation stands and provenance resource stands, using bulked seed by provenance;
4. to create breeding populations in breeding seedling orchards, using family-identified or bulked seed.

Requests should be sent to the OFI (see address above), stating clearly the type and composition of trial or planting planned, with a copy to FAO's Forestry Department (Via delle Terme di Caracalla, I-00100 Rome, Italy).

List of Pinus caribaea var. bahamensis seed samples available for international provenance testing, establishment of breeding base and gene conservation.

¹ Manuscript received March 1989

² FAO (1986). Forest genetics and seed production in Pinus caribaea var. bahamensis in the Bahamas. Draft Technical Report, based on the work of R.D. Barnes. UTF/BHA/003/BHA. FAO, Rome 36 pp.