Anatomía de la madera y alometría de veinte especies de Stenocereus (Cactaceae)

WOOD ANATOMY OF STENOCEREUS WAS STUDIED TO EVALUATE IF THERE ARE DIFFERENCES AMONG SPECIES AND TO EVALUATE IF FIVE QUANTITATIVE WOOD FEATURES ARE CORRELATED WITH PLANT HEIGHT. THE RESULTS SHOWED THAT THE SPECIES STUDIED POSSES THE TYPICAL FIBROUS WOOD OF CACTACEAE. COMMON FEATURES TO ALL SPECIES ARE DIFFUSE POROSITY WITHOUT CONSPICUOUS GROWTH RINGS, LIBRIFORM FIBERS, PARATRACHEAL PARENCHYMA, AND HETEROGENEOUS RAYS WITH PERFORATED RAY CELLS. CORRELATION ANALYSIS REVEALED A POSITIVE ASSOCIATION AMONG FOUR WOOD CHARACTERS AND PLANT HEIGHT. IN GENERAL, IF INDIVIDUALS HAVE SHORT SIZE ( <3 M TALL) THEIR VESSELS ELEMENTS AND FIBERS DECREASE. IN CONTRAST, TALLER INDIVIDUALS SHOW LONGER VESSELS ELEMENTS AND FIBERS. THIS BEHAVIOR DOES NOT OCCUR FOR RAY HEIGHT, SINCE SHRUBS LIKE S.BENECKEI OR TALL TREES AS FOR S. MARTINEZII POSSESS RAYS OF SIMILAR SIZE. THERE ARE NO CHARACTERS THAT HELP TO DISTINGUISH AMONG GROUPS OF SPECIES OF STENOCEREUS, EXCEPT FOR S. EICHLAMII, WHICH POSSESSES THE TALLEST RAYS.