Variability of leaf characteristics in different pedunculate oak genotypes (Ouercus robur L)

Abstract

The objective of this study was to determine genotype influences on pedunculate oak's leaf traits: leaf area, specific leaf area (leaf area per unit of leaf mass), concentration of photosynthetic pigments, rates of photosynthesis and respiration, and nutrient concentrations (nitrogen phosphorus, potassium, calcium, and sodium). Leaf samples were taken from seventeen Q. robur genotypes originating from clonal seed orchard Banov Brod (Srem, Vojvodina, Serbia). Leaf area of the studied genotypes ranged from 248.4 to 628.8 cm2, SLA from 109.4 to 160.7 cm2 dry matter-1, rates of photosynthesis and respiration from 6.98 to 20.32 and from 6.73 to 14.65 µmol O2 m-2 s-1, respectively. The leaves of genotype 35 contained the highest concentration of photosynthetic pigments, while the lowest were recorded in genotype 29. The following pattern of nutrient concentrations was obtained for the studied genotypes: N>Ca>K>P>Na. Genotype variability of P K, Ca, and Na concentrations was more pronounced when compared with nitrogen. Estimated quantitative differences are the consequence of interaction of certain genotype and common environmental conditions for all trees. These results will provide information on intraspecific variation of the studied leaf characteristics

Efecto de la fragmentación en la morfometría foliar y el ambiente de Quercus germana Schldl. & Cham. (Fagaceae) en Xalapa, Veracruz

“…La variación morfológica de las hojas de Quercus es de gran interés debido a que muchas especies están sometidas a una fuerte presión de selección local, que las ha llevado a la diferenciación entre poblaciones e individuos (González-Rodríguez & Oyama, 2005;TovarSánchez & Oyama, 2004;Sack et al, 2006). Las hojas son el principal órgano fotosintético de las plantas, lo que las hace altamente sensibles a cambios en la luz (Álvarez, Sánchez-González, & Granados-Sánchez, 2009;Halloy & Mark, 1996), ciclos fenológicos, ritmos de crecimiento (González-Rodríguez & Oyama, 2005;Nikolic, Krstic, Pajevic, & Orlovic, 2006), época del año y posición de la hoja en el árbol (Ponton, Dupoguey, & Dreyer, 2004). Además de las características biológicas intrínsecas de los árboles, existe un componente genético que explica la plasticidad foliar por expresión diferencial adaptativa, la cual es característica del género (González-Rodríguez & Oyama, 2005).…”

“…The morphological variation of the Quercus leaves is of high interest due to the fact that several species have been subjected to high local selection pressure, which has caused the differentiation between populations and individual subjects (González-Rodríguez & Oyama, 2005;Tovar-Sánches & Oyama, 2004;Sack et al, 2006). Leaves are the main photosynthetic organ of plants, which makes them highly sensitive to the changes in light (Álvarez, Sánchez-González, & GranadosSánchez, 2009;Halloy & Mark, 1996), phenological cycles, growth rates (González-Rodríguez & Oyama, 2005;Nikolic, Krstic, Pajevic & Orlovic, 2006), time of the year and position of the leaf in the tree (Ponton, Dupoguey & Dreyer, 2004). In addition to the intrinsic biological characteristics of the tree, there is a genetic factor that explains the foliar plasticity by adaptive differential expression, which is a characteristic of the genus (González-Rodríguez & Oyama, 2005).…”

“…Several studies on differentiation in some species of Quercus have been made in order to evaluate foliar variation, determining that the changes among populations are directly proportional to the environmental differences (Álvarez et al, 2009;González-Rodríguez & Oyama, 2005;Ponton et al, 2004;Tovar-Sánchez & Oyama, 2004). Even though environmental changes can be the result of fragmentation, the environment does not always determine the morphological changes as it has been shown in populations of Q. robur L., where the variation of the foliar characteristics is attributed to interruptions in the gene flow without the presence of environmental differences (Nikolic et al, 2006). Due to the foregoing, it is probable that the morphological differentiation could be attributed both to the environment and to interruptions in the gene flow; both situations are present in fragmentation events.…”

“…Múltiples estudios sobre la diferenciación en algunas especies de Quercus se han realizado para evaluar la variación foliar, determinando que los cambios entre poblaciones son directamente proporcionales a las diferencias ambientales (Álvarez et al, 2009;González-Rodríguez & Oyama, 2005;Ponton et al, 2004;Tovar-Sánchez & Oyama, 2004). Aunque los cambios ambientales pueden ser resultado de las fragmentaciones, el ambiente no siempre determina los cambios morfológicos como se ha mostrado en poblaciones de Q. robur L., donde la variación de las características foliares se atribuye a interrupciones del flujo genético sin presencia de diferencias ambientales (Nikolic et al, 2006). Debido a lo anterior es posible que la diferenciación morfológica pueda atribuirse tanto al ambiente como a interrupciones del flujo genético, ambas situaciones presentes en eventos de fragmentación.…”

Preliminary Study on Taxonomic Review Using Histological Sections of Some Iberian Species from the Genus <i>Quercus</i> L. (Fagaceae)

“…But in addition to these characteristics, there is also an influence of ecological factors, phenological cycles, growth rhythms, etc. [13] [14], which call for the utmost care when collecting samples for taxonomic studies. As far as it is practical, it is necessary to unify the greatest possible number of variables.…”