It has previously been shown that hydraulic conductance in bur oak leaves (Quercus macrocarpa Michx.), measured with the high pressure flow meter technique (HPFM), can significantly increase within 30 min following exposure to high irradiance. The present study investigated whether this increase could be explained by an increase in the cell-to-cell pathway and whether the response is linked to ...

Substrate and rhizosphere microorganisms are key factors affecting seedling growth; however, the effects of substrates bacteria on growth Quercus variabilis not completely understood. Here, Q. seedlings were grown in with without cork flour, as follows: H substrate (charcoal soil/cork flour/perlite, 1:1:2), S (cork 1:1), control (CK) soil/perlite, 3:2). High-throughput sequencing qPCR used to i...

Tree decline is a physiological phenomenon resulting from climatic disturbances that involves damage to forest ecosystems. This study examined the effects of tree on nutrient concentrations in leaves, bark, and wood Persian oak (Quercus brantii) trees. Trees were categorized by severity (healthy, slight, moderate, severe decline). Leaves collected middle outer parts crowns. Bark samples taken a...

Leaves constitute a substantial fraction of the total resistance to water flow through plants. A key question is how hydraulic resistance within the leaf is distributed among petiole, major veins, minor veins, and the pathways downstream of the veins. We partitioned the leaf hydraulic resistance (R(leaf)) for sugar maple (Acer saccharum) and red oak (Quercus rubra) by measuring the resistance t...

Background and objectives: Quercus brantii subsp. persica is used in folk medicine to treat infections in Iran. There is not available report on the anti-biofilm activity of Quercus brantii subsp. persica. The aim of the present study was to investigate the effects of Quercus brantii subsp. persica against bacterial biofilms. Methods: Eighty biofilm producing strains of Staphylococcus aureus, S...

A four- to seven-fold enhancement of leaf hydraulic conductance by light has been reported in three temperate tree species. The enhancement occurs in the liquid-flow pathway between the petiole and the site of water evaporation. The enhancement occurs within 1 h, and dissipates in darkness over a period of 1 to 10 h depending on species. Here we report light-induced enhancement of leaf hydrauli...

Quercus pubescens Willd., a species distributed from Spain to southwest Asia, ranks high for drought tolerance among European oaks. Q. pubescens performs a role of outstanding significance in most Mediterranean forest ecosystems, but few mechanistic studies have been conducted to explore its response to environmental constrains, due to the lack of genomic resources. In our study, we performed a...

Daily variations in photoprotective mechanisms were studied in sun and shade leaves of 40-year-old cork oak (Quercus suber L.) trees during early summer in Portugal. Although trees were not severely water stressed because predawn leaf water potentials remained high, photosynthesis and stomatal conductance decreased at midday. The midday depression in gas exchange was not reversed by short-term ...

Quercus suber L. (cork oak) leaves were analyzed along one annual cycle for cuticular wax content and chemical composition. This species, well adapted to the long dry summer conditions prevailing in Mediterranean, has a leaf life span of about year. The revealed seasonal variation with coverage increase from newly expanded (115.7 µg/cm2 spring) maximum value fully (235.6 after summer). Triterpe...

Nitrogen (N) retranslocation within tree canopies has been intensively studied and assumed to function as a one-way process (e.g., from older to newer leaves). However, recent studies have found that both N output and input occur in individual leaves, suggesting that 'gross' N retranslocation exists behind 'net' N retranslocation. In the present study, the amount and direction of gross N retran...