Gall oak has a large ecological adaptability landscape and social importance it is share of the natural wealth great economic value. Polyploidy deducted in this study through pre-screened directly by determining stomata guard cell length then confirmed quantifying DNA content using SCoT-PCR analysis. Depending as method we found maximum tetraploids (4n) mixoploids (3n) plants were induced chlci...

To determine the biochemical basis of osmotic adjustment, seasonal and treatment differences in foliar water- soluble organic solutes and inorganic ions were investigated for two hardwood species that exhibited osmotic adjustment in a Throughfall Displacement Experiment at the Walker Branch Watershed near Oak Ridge, Tennessee. Leaf samples of overstory and understory chestnut oak (Quercus prinu...

We investigated light acclimation in seedlings of the temperate oak Quercus petraea (Matt.) Liebl. and the co-occurring sub-Mediterranean oak Quercus pyrenaica Willd. Seedlings were raised in a greenhouse for 1 year in either 70 (HL) or 5.3% (LL) of ambient irradiance of full sunlight, and, in the following year, subsets of the LL-grown seedlings were transferred to HL either before leaf flushi...

We assessed the eVect of whole-stream nitrate enrichment on decomposition of three substrates diVering in nutrient quality (alder and oak leaves and balsa veneers) and associated fungi and invertebrates. During the 3-month nitrate enrichment of a headwater stream in central Portugal, litter was incubated in the reference site (mean NO3-N 82 g l ¡1) and four enriched sites along the nitrate grad...

Even when introduced invasive pathogens lack their natural predators or competitors, they must still interact with other organisms in their introduced range. Sudden Oak Death (SOD), caused by Phytophthora ramorum (Oomycota), is an introduced disease causing large-scale tree mortality. Two additional Phytophthora species, Phytophthora nemorosa and Phytophthora pseudosyringae, cause significantly...

Foliar samples were harvested from two oaks, a beech, and a yew at the same site in order to trace the development of the leaves over an entire vegetation season. Cellulose yield and stable isotopic compositions (δ(13)C, δ(18)O, and δD) were analyzed on leaf cellulose. All parameters unequivocally define a juvenile and a mature period in the foliar expansion of each species. The accompanying sh...