Provenance variation and provenance-site interaction in Pinus brutia TEN.:Consequences of defining breeding zones

Forty-nine provenances of Pinus brutia were tested on 13 sites in Turkey, a nd 10-year results were evaluated. Provenances did not differ for survival except at two sites. There were highly significant differences among the pr ovenances in height and diameter in all test sites located in the Mediterra nean, Marmara and in the southeastern regions of Turkey. However, provenanc es did not differ in Aegean region sites except for diameter at one site. T he fastest growing provenances had up to 55% greater height and 50% greater diameter than the site means, implying considerable gain can be realized i f the best provenances were selected for plantations. Provenances from the middle elevation zone (400 m to 900 m) of the Mediterranean region had grea ter growth than the provenances from peripheral distribution of the species at most sites. In general, the results did not support seed transfer zoning which was base d on geographic and climatic data. Sub zoning of the Aegean region was not justified, as type B provenance correlations were high, well over the thres hold value (r(B) = 0.8). For northern Marmara (Kesan site) and southeast An atolia regions, a land race should be developed. Provenances were significa ntly different for stability variances, indicating the potential to select for stable genotypes across sites or for genotypes that are the most produc tive at specific sites.