ECOLOGICAL WOOD ANATOMY OF Miconia sellowiana (MELASTOMATACEAE) IN THREE VEGETATION TYPES OF PARANÁ STATE, BRAZIL

Miconia sellowiana (Melastomataceae), a widespread species occurring in Araucaria Forest, Montane Dense Forest and Upper Montane Forest (Parana state, Brazil) has a highly variable foliar morphology. This study investigated whether the wood anatomy follows this pattern influenced by environmental conditions. Samples of six individuals per area were collected, fixed and prepared, according to standard techniques in wood anatomy. ANOVA indicated differences for length and diameter of vessel elements and fibres, fibre wall thickness, width of rays and ray frequency, especially regarding the population of the Upper Montane Forest. The secondary xylem from this vegetation is characterized by shorter vessel elements and fibres, thicker fibre walls and wider rays. These characteristics are associated to a certain degree of water stress imposed to the plants in the Upper Montane Forest, mainly due to the shallow neosol soils. The Araucaria Forest and the Montane Dense Forest have more similar environmental conditions, supported by the Cluster analysis. The Principal Components Analysis explained 98% of the total variance, where fibre and vessel element lengths showed a posi-tive correlation; however, this analysis did not allow the separation of three distinct groups. Although less pronounced, the wood anatomical differences corroborate the results obtained with foliar morphology, where leaves from the Upper Montane Forest presented the most xeric characteristics among the populations of Miconia sellowiana studied.