Genetic parameters and provenenance variation of Pinus caribaea var. hondurensis in 48 international trials

A total of 23 provenances or sources of Pinus caribaea var. hondurensis (Se necl) Barr. et Golf. were tested in 48 provenance-progeny trials in Colombi a, Brazil, and Venezuela. In Brazil and Venezuela, 8-year heights were appr oximately 12 m, while in Colombia, mean 8-year height was less than 8 m. Th e growth rates of the unimproved material correspond approximately to volum es of 14-15 m(3).ha(-1).year(-1) of wood on sites in Brazil and Venezuela, and 4-5 m(3).ha(-1).year(-1) in Colombia. Provenances had similar growth ra nkings in the different countries, with a type-B provenance correlation of 0.63. The best native provenances were Limon and Guanaja, Honduras. Improve d first-generation sources from Queensland, Australia and Zululand, South A frica, were 5-12% better than the mean of the unimproved provenances, depen ding on country where planted. Mean single-site heritability for volume gro wth is approximately 0.18. Potential genetic gain for volume at 8 years fro m selection within provenance is around 30%. Foxtailing is also under moder ate genetic control with heritability around 0.15. Genotype x environment i nteraction for volume growth is generally higher for tests located in diffe rent countries than in the same countries. Selection for age-8 volume using age-5 data would be 93% as effective as selection at age 8.