Effects of stem anatomical and structural traits on responses to stem damage: an experimental study in the Bolivian Amazon

Abstract

Persistence of tree species in a habitat depends on their ability to avoid and respond to disturbance-related damage. Responses to stem damage vary among species but typically include bark wound closure and prevention of xylem decay spread. These responses are associated with anatomical, structural, and physiological traits. This study explores how xylem (vessel size and (or) abundance, parenchyma abundance, ray width, and wood density) and phloem (bark thickness, proportion of live inner bark, ray width and (or) dilation, inter-ray distance, and tissue density) traits relate to responses to stem damage in seven species from the Bolivian Amazon. Rates of bark wound closure and radial xylem decay penetration were compared 2 years after experimental damage. A species that closed bark wounds rapidly (100% in Chorisia speciosa A. St.-Hil.) was not efficient at constraining xylem radial decay spread (1.7 mm). The opposite was true for Pseudolmedia laevis (Ruiz & Pav.) J.F. Macbr., a species that closed wounds slowly (30%) but efficiently controlled decay spread (0.5 mm). The relationship between anatomical and (or) structural traits and damage response variables revealed that species with favorable traits for rapid wound closure (e.g., widely dilating rays) had traits that favored xylem decay spread (e.g., low wood density). It is plausible that this apparent trade-off is based on physiological and phylogenetic constraints.

Tree response to bark harvest: the case of a medicinal species, <i>Garcinia lucida</i>, as source of raw materials for plant-based drug development

“…As G. lucida is also an Atlantic forest species, it is likely that the remaining narrow bark strips, as well as the yellow and resinous exudates produced along the sides of wounds after bark stripping, may have served to provide the necessary humidity to trigger the cellular division process that had culminated in the recovery of injured xylem and phloem. Romero & Bolker (2008) have studied the effects of debarking in seven species and found that species that produce some type of exudate showed more efficient bark recovery. Cunningham (2001) also found that plants of certain families, such as Apocynaceae, Euphorbiaceae, Moraceae and Canellaceae, show great resilience after debarking, in part because the cambium was protected by exudates after the bark removal.…”

Causes and implications of the correlation between forest productivity and tree mortality rates

“…While these last observations do not prove that a greater proportion of trees suffer pathogenic fungal attack at BCI than in the Pacific States (because not all fungipolypore or otherwise-are pathogenic, and not all trees infected by fungi show visible fungal fruiting bodies), they are certainly suggestive. Finally, two years after the boles of Bolivian humid forest trees of seven species (including three that produced abundant latex) were experimentally wounded, ;99% of trees showed decay in the wounds (Romero and Bolker 2008). In contrast, decay was found in only one half of bole wounds averaged over six of our Pacific States gymnosperm species (Vasiliauskas 2001), even though the wounds were generally orders of magnitude larger and much older, providing greater opportunities for fungal infection.…”

Assessment of risks and potential of injection techniques in integrated programs to eradicate the red palm weevil: review and new perspectives

“…The absence of this natural compartmentalization capacity of wounds would constitute such a serious evolutionary disadvantage that it would not have allowed the sustainable emergence of perennial species [3,[35][36][37][38]. It is thanks to this natural capacity that pruning, often much more aggressive than injection, constitutes a current practice in arboriculture.…”