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.

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.

In the present study, variations of leaf stomatal traits for fourteen European beech provenances (Fagus sylvatica L.), originating from six countries (Bosnia and Herzegovina, Croatia, Germany, Hungary, Romania and Serbia), were evaluated at the inter-and intra-provenances levels. Ten stomatal traits (stomatal density (SD), guard cell length (LA) and width (WB), stomatal aperture length (La) and width (Wb), pore surface of guard cell (SPSLAWB), pore surface of a widely opened pore (SPSLaWb), coefficient (SSC), potential conductance index (PCI) and relative stomatal pore surface (RSPS)) were examined using methods of univariate (ANOVA and Tukey's HSD test) and multivariate statistical analyses (principal component analysis (PCA), discriminant analysis and cluster analysis). The results obtained provide significant insight into the genetic diversity and differentiation of European beech provenances and confirmed high genetic variability within and between examined European beech provenances, according to all examined parameters. Differences at the intra-provenance level had a bigger impact on most of the 938

The beneficial role of fungi from the Trichoderma genus and its secondary metabolites in promoting plant growth, uptake and use efficiency of macronutrients and oligo/micro-nutrients, activation of plant secondary metabolism and plant protection from diseases makes it interesting for application in environmentally friendly agriculture. However, the literature data on the effect of Trichoderma inoculation on tomato fruit quality is scarce. Commercially used tomato cultivars were chosen in combination with indigenous Trichodrema species previously characterized on molecular and biochemical level, to investigate the effect of Trichoderma on photosynthetic characteristics and fruit quality of plants grown in organic system of production. Examined cultivars differed in the majority of examined parameters. Response of cultivar Gružanski zlatni to Trichoderma application was more significant. As a consequence of increased epidermal flavonols and decreased chlorophyll, the nitrogen balance index in leaves has decreased, indicating a shift from primary to secondary metabolism. The quality of its fruit was altered in the sense of increased total flavonoids content, decreased starch, increased Bioaccumulation Index (BI) for Fe and Cr, and decreased BI for heavy metals Ni and Pb. Higher expression of swolenin gene in tomato roots of more responsive tomato cultivar indicates better root colonization, which correlates with observed positive effects of Trichodrema.

In this study we have investigated the effect of T. harzianum on growth, content of chlorophyll and epidermal flavonols and metal distribution in tomato plants. Trichoderma strain, isolated from the A horizon (5-30 cm) of agricultural soil used in organic production, was applied near the root in the sixth leaf development phase of tomato. Tomato plants were grown in a growth cabinet up to the stage of 10 leaves. Content of chlorophyll (Chl), epidermal flavonols (Flav) and antocyanins (Ant) were measured in vivo non-destructively. The concentration of Cd, Co, Cu, Cr, Fe, Mn, Ni, Se, and Zn was measured in different parts of tomato plants by ICP-OES method. Results have shown that Trichoderma application positively affected growth of tomato plants, and significantly decreased nitrogen balance index. In Trichoderma treated plants the contents of Cr and Ni were significantly reduced in roots, while content of Cd tended to decrease in all plant parts, significantly in roots. Presented results indicate that investigated isolate is worthwhile testing for plant growth promotion in field conditions, taking in account different supply of macro and micronutrients.

Извод: Две half-sib линије храста цера (Quercus cerris L.) (C1 и C2) су у полу-контролисаним условима биле изложене различитим третманима: оптималној влажности земљишта-контрола (К), суши праћеној опоравком након поновног успостављања оптималне влажности земљишта (T1) и третману константне суше (T2). Испитиване су промене физиолошких параметара везаних за процес фотосинтезе у корелацији са примењеним третманима. Третман T2 је утицао на значајну редукцију интензитета фотосинтезе, стоматалне проводљивости и тренутне ефикасности коришћења воде, као и на сигнификантно повећање интерцелуларне концентрације CO 2 код обе half-sib линије. У односу на контролу, третман T2 није довео до значајног варирања максималне фотохемијске ефикасности код испитиваних half-sib линија. На третману T1, друга half-sib линијa (C2) показала је бољу способност опоравка интензитета фотосинтезе и стоматалне проводљивсти након поновног заливања, док је на истоименом третману пре опоравка ефикасније користила воду у поређењу са првом half-sib линијом (C1). Резултати истраживања указују на специфичне адаптивне предиспозиције испитивних half-sib линија у односу на сушни стрес и опоравак.

S a š a S . O R L O V I Ć 2 , M i r j a n a M . B O J O V I Ć 3 , L a z a r A . K E S I Ć 2 , P r e d r a g L . P A P 2 , S r đ a n

In the present study we compared the physiological performances of Prunus avium L., Robinia pseudoacacia L., Juglans nigra L., and Populus x euramericana cl. Pannonia, planted at the coal mine tailings of the Mining Basin "Kolubara" (Serbia), to assess the potential of different tree species for land reclamation. The measurements were conducted during three consecutive years characterized by contrasting climatic conditions (wet and drought). The results showed that the rate of net photosynthesis (A), stomatal conductance (gs) and transpiration rate (E) sharply declined in two dry years in all tree species. These trends were particularly evident for R. pseudoacacia and J. nigra, in which A, gs and E were twice as low during the dry years. On the other hand, R. pseudoacacia and P. x euramericana cl. Pannonia seedlings were characterized by the highest water-use efficiency and intrinsic water-use efficiency during the dry years, indicating that these species are more efficient responders to drought, due to their ability to maintain a balance between the loss of water and the CO2 assimilation rates. The survival rate of the examined tree species was high (>86%) and increased in the following order: P. avium < J. nigra < R. pseudoacacia < P. x euramericana cl. Pannonia. Based on the obtained results we recommend R. pseudoacacia and P. x euramericana cl. Pannonia as a good solution for afforestation and revitalization of degraded habitats, such as coal mine tailings, although high survival rate, observed in P. avium and J. nigra, makes these two species a candidate for planting during degraded sites reclamation, as well.