Modificaciones en la corteza de Prosopis laevigata por el establecimiento de Tillandsia recurvata

Abstract

The growth of Tillandsia recurvata on Prosopis laevigata branches seems to cause various degrees of damage. In this study the possible anatomical modifications in the bark of the phorophyte P. laevigata caused by the epiphyte T. recurvata are studied. When the epiphyte has not yet established, the bark of P. laevigata displays the typical distinctive non-collapsed and collapsed phloem, cortex and periderm similar to those described for other leguminous species. However, once T. recurvata is established on P. laevigata branches there are modifications in various tissues: the occurrence of a wound periderm and the occlusion of cortex and collapsed phloem cells with dark extractives as a chemical barrier for defence against infections. When the epiphyte has been vigorously attached for a long time to the bark, the damage is deeper in the tissues, thus affecting the wood. The most notorious change in the wood is related to a different distribution of secondary xylem cells and a reduction in the number and diameter of vessels. The impact of the epiphyte in the phorophyte may favor the occurrence of pathogen attacks in the phorophyte tissues.