New insights into wood anatomy and function relationships: how Eucalyptus challenges what we already know

FERNÁNDEZ M.E.; BAROTTO JA; MARTINEZ-MEIER A; GYENGE JE; TESÓN N; ALARCÓN P.; BARIGAH T; QUIÑONES MARTORELLO, A.; MERLO SANCHEZ, E.; DALLA SALDA G; ROZENBERG P; MONTEOLIVA S

Bariloche

Conferencia; International Conference: Adapting forest ecosystems and wood products to biotic and abiotic stress; 2019

LIA Forestia - INTA (Argentina) e INRA (Francia)

Multispecies surveys have shown thatthere is a weak but significant tradeoff between xylem efficiency and safety inwoody species, and that there are no species occupying the space with highefficiency and high safety. Large vessels and tracheids result in high vulnerability to xylem cavitation (VC)due to tension, although there is not a direct causal relationship betweenconduct diameter and VC. Moreover, relationships between xylem structure andfunction are studied mostly at the interspecificlevel, with few studies considering the relationships at the intraspecificlevel, particularly in angiosperms. Recent studies in Quercusspecies have shown that trends between vessel diameter and VC observed at the interspecificlevel are contrary to that observed within one of the Quercusspecies. This raises the question about the value of multispecies studies toshed light over what is adaptive within a given species. Eucalyptusspecies share with Quercus a xylem anatomy composed by solitaryvessels surrounded and connected to imperforate tracheary cells and parenchyma. Contrary toresults in that genus, our results in four Eucalyptusspecies revealed that the trends observed between vessel size (mean anddistribution) and VC are similar at the interspecific and intraspecific (E.globulus)levels. No tradeoff was observed between xylem efficiency and safety: thelarger the vessels, the lower the VC. The amount of cells around vessels couldbe involved in this phenomenon. Also, stem wood density correlates withbranches VC across species and within E. globulus.Trends observed in this genus challenge what we already know about xylemanatomy and function, and may help to widen our vision about the role of woodin adaptation to drought stress.