The general aim of this work was to compare the leaf-level responses of different protective components to water deficit and high temperatures in Quercus cerris L. and Quercus robur L. Several biochemical components of the osmotic adjustment and antioxidant system were investigated together with changes in hormones. Q. cerris and Q. robur seedlings responded to water deficit and high temperatures by: (1) activating a different pattern of osmoregulation and antioxidant mechanisms depending on the species and on the nature of the stress; (2) upregulating the synthesis of a newly-explored osmoprotectant, dimethylsulphoniopropionate (DMSP); (3) trading-off between metabolites; and (4) modulating hormone levels. Under water deficit, Q. cerris had a higher antioxidant capacity compared to Q. robur, which showed a lower investment in the antioxidant system. In both species, exposure to high temperatures induced a strong osmoregulation capacity that appeared largely conferred by DMSP in Q. cerris and by glycine betaine in Q. robur. Collectively, the more stress-responsive compounds in each species were those present at a significant basal level in non-stress conditions. Our results were discussed in terms of pre-adaptation and stress-induced metabolic patterns as related to species-specific stress tolerance features.

Background and purpose: This paper analyses the lead tolerance and accumulation in white poplar genotypes in vitro, in order to optimize genotype evaluation and other procedures in their implementation in phytoremediation projects and landscaping in areas endangered by lead accumulation. Material and Methods: The lead tolerance and accumulation of five white poplar genotypes after 35 days in vitro cultivation on media supplemented with lead was examined. The following Pb(NO 3) 2 concentrations were used: 0, 10-6 , 10-5 , 10-4 and 10-3 M. Tolerance analysis (described by tolerance indices) was based on morphological parameters, biomass accumulation and the content of photosynthetic pigments, while lead accumulation was described by shoot lead accumulation and shoot lead content. Results and Conclusions: The chosen lead concentrations appeared not to be lethal. Moreover, the obtained results showed that the tested lead concentrations had a positive effect on: number of formed roots, shoot moisture content and shoot height. The best differentiation among the examined genotypes was gained by the tolerance index based on the shoot height on 10-4 M Pb(NO 3) 2. The shoot lead accumulation and shoot lead content significantly increased on 10-4 and 10-3 M Pb(NO 3) 2 media. Thus, the concentration of 10-4 M Pb(NO 3) 2 is recommended for further research. Two examined genotypes of horticultural value (LCM and LBM) achieved a significantly higher lead shoot content compared to the wide spread genotype "Villafranca" (almost 200% and 125% higher, respectively).

Although sessile oak is one of the most important deciduous forest tree species in Europe, data on the diversity of ectomycorrhizal (ECM) fungi on sessile oaks in the Republic of Serbia are scarce. The aim of this study was to provide the first insight into the diversity of ECM fungi on sessile oak in Serbia. Two sites Info center and Brankovac, located in National Park Fruška gora were chosen. ECM fungi were identified combining morphological and anatomical characterization with molecular analysis of nuclear rDNA internal transcribed spacer (ITS) region. All vital ECM root tips were counted, diversity indices were calculated, and ECM fungi were classified into the exploration types. The granulometric and chemical composition of soil were analyzed as well. At both sites, 26 different ECM fungal taxa were recorded in total, 17 taxa were observed at the site Info center and 12 taxa at Brankovac. ECM communities consisted of a few abundant taxa and a larger number of rare taxa. Lactarius quietus, Cenococcum geophilum, and Tomentella sublilacina were recorded at both sites. High abundance of contact and short-distance exploration types recorded in studied stands suggests that soils are sufficiently rich in total nitrogen and organic matter. Values of diversity indices recorded in studied sessile oak stands from Fruška gora were lower in comparison to those obtained in stands of different oak species across Europe which is likely induced by drought. To get a more thorough insight into the diversity of ECM fungi on sessile oak, research should be continued at more sites and seasonal dynamics should be included.

Aim of study: In the present paper we studied the nature and level of co-dependence between leaf functional traits and intrinsic water-use efficiency (WUEi)in one-year-old Quercus roburL. seedlings, grown in a common garden experiment under moderate drought conditions. The study aimed to identify those traits that might be potentially utilized to improve leaf-level WUEi, and therefore be used in breeding programmes to enhance drought adaptation of Q. roburtree species.Area of study: The study was carried out at the common garden experiment established within UNESCO Biosphere Reserve Mura-Drava-Danube.Material and methods: The study involved one-year-old seedlings of eight half-sib lines of Q. robur. We analyzed 18 leaf parameters; i.e. physiological, biochemical, morphological and anatomical. Data were processed using multivariate statistical methods: a) principal component analysis, b) stepwise regression analysis, and c) path coefficient analysis.Main results: The results evidenced that leaf stomatal traits, particularly stomatal density (SD),and leaf dry mass per unit leaf area (LMA) were the most important traits associated closely with WUEi.Stomatal density achieved the highest score on PC1 (0.825), in which WUEihad the highest loading (0.920), as well. SDwas also included first in stepwise regression model. Research highlights: The results demonstrated that under moderate water stressWUEiin Q. robur half-sib lines were mainly the result of the plants’ structural acclimation to surrounding environmental conditions.

Broomrape is a parasitic plant that significantly decreases yield of sunflower. Breeding for resistance has proved to be the most efficient method for suppressing broomrape infestation in the field; however, new races of parasite constantly emerge, and new resistance genes need to be discovered and introduced into cultivated sunflower lines. The aim of this work was to test SSR markers from linkage group 3 (LG3) to investigate whether they could be used for identification of a particular Or gene. Twenty sunflower inbred lines were used, and polymorphism between the lines with various resistance genes and genetic background was investigated. The used markers revealed DNA polymorphism between the investigated lines. Strong association of markers from LG3 with Or 6 , as well as Or 4 and Or 2 genes, was found. Identified markers could be used for introduction of these resistance genes into commercial sunflower lines and for establishment and identification of differential lines.