Anatomical and tree rings differences in two provenances of Cordia trichotoma (Vell.) Arráb. ex Steud. (Boraginaceae)

Abstract

The parental effect on wood anatomy and growth rings of Cordia trichotoma trees was studied. Tree seeds of two provenances (Cerrado and Atlantic Forest biomes) were collected in 1986. Seedlings were planted, and after 25 years, twelve wood disks were collected from six trees from each provenance. Anatomical features and growth rings were analyzed according to standard techniques. Qualitative anatomy of wood indicated similarities between the two provenances, except for the presence of geniculate vessels found in woods from the Cerrado. However, the greatest differences in wood anatomy were quantitative. Provenances from Cerrado had wood with shorter vessel and fibers elements, less fiber lumen, less parenchyma per mm 2 , and more vessels per group than did provenances from the Atlantic Forest. Cross dating among the radial growth ring series was performed through visual and statistical procedures. The relationships between tree rings and meteorological records were performed through Pearson's correlation, and through dendro-climatic analysis that identified the end summer precipitation as the major factor affecting tree growth at inter annual timescale. The standard chronologies of tree-ring width series showed similarity between Cerrado and Atlantic Forest provenances, but with small differences in the juvenile period of live of trees. The rains that decreased between April and June associated with the gradual decrease in temperature may have reduced the cambial activity and caused the formation of tree rings with small differences between the two provenances. The results of this study are relevant for climate adaptive forestry: they emphasize the importance of heritability in the plasticity of certain features of wood anatomy related to the environmental conditions in which they grow, while the growth rate and its year-by-year variability show small differences. mostraram similaridade entre as procedências do Cerrado e da Mata Atlântica, mas com pequenas diferenças no período juvenil de vida das árvores. As chuvas que diminuíram entre abril e junho associadas à diminuição gradativa da temperatura podem ter reduzido a atividade cambial e ocasionado a formação de anéis das árvores com pequenas diferenças entre as duas procedências. Os resultados deste estudo são relevantes para a silvicultura adaptativa ao clima, e enfatizam a importância da herdabilidade na plasticidade de certas características da anatomia da madeira relacionadas às condições ambientais em que crescem, e a taxa de crescimento e sua variabilidade ano a ano também mostram pequenas diferenças. similar to for Prosopis flexuosa studied in a seasonal dry environment in Argentina and different from Tectona grandis from a seasonal dry environment in the central region of Brazil the occurrence of different types of false growth rings. alliodora tree-rings. Intra-annual density some in dating the also irregularity in width along the stem Tschinkel out that in C. alliodora the rings close to the pit were not formed or were indistinct, it to date the first life rings of some trees. In eccentric it difficult to identify the pattern of growth Differences in seasonal increment patterns of C. alliodora circumference were also shown by Hazlett and are related to tree age; seasonal rainfall distribution; reproductive phenology and, to a lesser degree, the seed source of a plantation.