Genetic Study and Pulpwood Selection of Loblolly Pine Provenances Ⅰ.Geographical Variation and Correlation Analyse of Economic Traits

The 3 provenance tests of 9a, 11a, 12a in Zhejiang Province, including 74 loblolly pine seed sources, were studied.Many variables of growth, yield, tree form and wood property showed there were more significant difference among provenances with above moderate heritability, the variation of stem dry weight was more significant than that of the other traits.There was complex relationship between the provenance variation of variables and the climatic factors and geographical position of seed sources.The intercorrelations between important traits were also diversified, every correlation coefficent of stem volume and dry weight was above 0.95, wood density were negatively correlated with growth and yield traits, and positively correlated with tree form traits.