Pattern of leaf vein density and climate relationship of Quercus variabilis populations remains unchanged with environmental changes

Abstract

The leaf vein traits of plants result partially from adaptations to environmental factors during the longterm evolution. However, no general conclusion on the variation trend of the vein density along a climate gradient or the response of such vein density-climate relationship pattern to climate changes has been made. We examined the variations in leaf vein density and other leaf traits of oriental oak (Quercus variabilis) in 10 in situ populations (in situ populations) across temperate-subtropical biomes and the response of the leaf vein density to environmental changes in 7 populations grown in a common garden (garden populations). The results show that the minor vein density of the in situ populations (C3rd order) significantly decreased with increasing latitude (r 2 = 0.44 and P = 0.04). This pattern remained unchanged for the garden populations (r 2 = 0.67 and P = 0.02). The minor vein densities of both the garden and in situ populations were positively correlated to the mean annual temperature (MAT) of the origins (r 2 = 0.66 and P = 0.03 for the garden populations; r 2 = 0.37 and P = 0.06 for the in situ populations), but their correlation to the mean annual precipitation (MAP) of the origins was not significant. Compared with the MAT and MAP, the vein density displayed a significantly lower correlation to climate variables in the current year or the current-year growing seasons. For the garden populations, the minor vein density significantly increased with leaf dry mass per area and decreased with petiole length and leaf length. These results imply that leaf vein density is genotypically fixed and is therefore not responsive to temporal changes in the growing conditions.

Traffic effects on leaf macro- and micro-morphological traits

“…3). The results of PL were different from Fallah et al (2012), but these results confirm the results of Sack et al (2003), Yousefzadeh et al (2009), Ghorbanli et al (2009) and Zhu et al (2012). It seems that each plant has its own plasticity-related strategy because there have been presented different reports for different species.…”

“…In general, the number of veins (V) and stomatal dimensions (SL, SW) has minimal plasticity, and stomatal density and leaf dimensions have the highest variability (Zhu et al, 2012). Zhu et al (2012) found that the vein density was less sensitive to environmental changes, and these authors also report that the vein trait was a protected trait. In general, different environments, and consequently different microclimates can affect the variability in leaf quantitative traits.…”

Phenotypic plasticity of European beech (Fagus sylvatica L.) stomatal features under water deficit assessed in provenance trial

“…The plasticity of stomatal density depends on more environmental factors, such as: air humidity (Torre et al 2003), vapor pressure deficit (Leuschner 2002), temperature (Beerling and Chaloner 1993;Zhu et al 2012), etc. For instance, Lichtenthaler et al (1981) reported that sun leaves of beech possessed significantly higher stomatal density than shade leaves.…”

Leaf Venation Variation and Phenotypic Plasticity in Response to Environmental Heterogeneity in Parrotia subaequalis (H. T. Chang) R. M. Hao et H. T. Wei, An Endemic and Endangered Tree Species from China

“…Vein traits are thought to reflect the gas and water exchange conditions at the interface between the leaves and the atmosphere, which are greatly influenced by the climatic factors affecting the leaf [11,12]. Studies focusing on interspecific patterns between plant traits and climatic factors have identified a correlation between leaf vein density and mean annual precipitation (MAP), and dryness of soil water availability can lead to higher leaf venation densities [13]. Phenotypic plasticity is one of two complementary ecological strategies and it refers to the ability of a specific genotype to shape various phenotypes in response to environmental variation [14].…”

“…Venation properties have been recognized as a type of phenotypic plasticity that is caused by ontogeny. There have been numerous reports on the correlations between leaf vein density and leaf area [15], epidermal cell size [16], stomatal density [17][18][19], stomatal conductance [19], hydraulic conductance [19,20], and photosynthesis [13]. However, variations in leaf venation and leaf vein density under different environmental conditions have not been widely reported until recently [21], especially for endangered species.…”