Is ball moss (Tillandsia recurvata) a structural parasite of mesquite (Prosopis laevigata)? Anatomical and ecophysiological evidence Article uri icon

abstract

  • Key message: The epiphyte Tillandsia recurvata modifies the anatomy of the xylem, phloem and periderm of its host Prosopis laevigata, these modifications affect water flux and photosynthetic activity in this host. Abstract: The relationships between epiphytes and host plants are commensal interactions, where epiphytes obtain support to growth without damaging their hosts. However, some epiphytes may cause the death of branches in their hosts. Ball moss (Tillandsia recurvata) is an epiphyte with elevated reproductive success in semiarid zones of México, growing mainly on mesquite trees (Prosopis laevigata). Mesquites are of great ecological and economical importance in central and northern Mexico, but the elevated mortality of branches and even whole trees have been associated with high ball moss loads. This study evaluates whether ball moss causes structural damage in the phloem, xylem, and periderm of mesquite branches, also testing whether the physiological performance of these branches was reduced. For this we measure the effective quantum yield of photosystem II (ΦPSII), hydraulic conductivity, water flux, number of vessels and the effective area of conduction in mesquite branches with and without ball moss. The results demonstrated that juvenile ball moss only affected the periderm and the collapsed phloem with no damage to non-collapsed phloem or xylem, but the reproductive individuals modified the anatomy of the xylem, phloem and periderm of mesquite. These structural modifications affected both water flux and hydraulic conductivity and reduced the ΦPSII. Our findings suggest that structural and ecophysiological changes induced by the ball moss are the cause of high branch mortality in mesquite. This is the first study showing anatomical and ecophysiological evidence of an epiphytic plant damaging its host. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.

publication date

  • 2021-01-01