| Abstract Detail
Ecophysiology Arenas Navarro, Maribel [1], Oyama, Ken [2], García Oliva, Felipe [3], Torres Miranda, Andres [2], Terrazas, Teresa [4]. Comparative wood anatomy of 21 oak species (Quercus) along an environmental gradient in western Mexico. Quercus (oaks) are a dominant woody plant genus that occupies habitats that range from dry chaparral to cloud forests. Mexico host more than 161 species of oaks species, of which 69% are endemic to the country, and 32 (19%) species are in some category of risk, according to the IUCN. The Serranias Meridionales floristic province in the southern highlands of Jalisco is considered a biodiversity hot spot with more than 22 oak species distributed along an environmental and elevational gradient which reflects several ecological strategies related to leaf and wood stem traits. Variation in wood anatomical traits represents adaptive structural solutions to achieve an optimal balance among the support, storage, and transport needs. In different proportions, angiosperm wood comprises several distinct cell tissue types, such as vessels, fibers, tracheids, and parenchyma, implying a wide dimension of anatomical variation. This study analyzed the wood anatomical traits and the xylem tissue fraction of 21 oak species to quantify the variation along an environmental gradient and analyze the interspecific variation. As a result, fibers and parenchyma fractions were the most abundant tissues. We found a trade-off between the total fiber fraction and the total parenchyma fraction driven by the precipitation of the warmest quarter in the region. The 21 oak species analyzed showed vasicentric tracheids driven by lower aridity index values which mean higher temperatures, which could be essential to compensate for a weakening of tissue strength because of abundant parenchyma. Also, we found that oak species with more vasicentric tracheids had smaller length fibers. Wood density was negatively correlated with the axial parenchyma fraction and width of the fiber lumen. Oak species with the narrower fiber lumen have higher densities and lower axial parenchyma fraction, showing that the increase in wood density was driven by a decrease in fibers diameter and lumen, which would mean that having more fibers with a smaller diameter makes them heavier. Also, denser wood with narrower fiber lumen tends to be smaller trees in drought sites, while taller oak trees will tend to have a wide fiber lumen fraction with lower wood densities in humid sites. For last, oak species have a significant interspecific variation in the proportions of xylem tissue and anatomical traits. The total vessel fraction and the vessel diameter are the traits with the most significant variations among species. Anatomical variation in oak species along an environmental gradient showed a broad continuum of fiber characteristics from wide to narrow wall and lumen, abundant to scarce parenchyma, and wide to narrow vessels. The analyzed oak species in Mexico distributed along mountain systems present a wide wood trait variation.
1 - Escuela Nacional de Estudios Superiores Unidad Morelia, Antigua Carretera a Pátzcuaro 8701, Morelia, MICH, 58190, Mexico
2 - Universidad Nacional Autónoma de Mexico, Escuela Nacional de Estudios Superiores Unidad Morelia, Antigua Carretera a Pátzcuaro 8701, Morelia, MICH, 58190, Mexico
3 - Universidad Nacional Autonoma de México, Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Antigua Carretera a Pátzcuaro 8701, Morelia, MICH, 58190, Mexico
4 - Universidad Nacional Autónoma de México, Instituto de Biología, Ciudad Universitaria, Coyoacán, CDMX, CDMX, 04510, Mexico
Keywords:
vasicentric tracheids
xylem
parenchyma.
Presentation Type: Poster
Number: PPE005
Abstract ID:541
Candidate for Awards:Physiological Section Physiological Section Li-COR Prize |
