Free radical scavenging activity of three Equisetum species from Fruska gora mountain

The scavenger activities of Equisetum arvense, Equisetum ramosissimum and Equisetum telmateia aboveground parts phosphate buffer (pH 7) extracts were evaluated using three different methods: DPPH assay, ESR and NO radical inhibition assay. Total reducing power was determined by FRAP assay. The E. telmateia extract demonstrated the most relevant scavenger and antioxidant properties. ESR signal of DMPO-OH radical adducts in the presence of E. telmateia phosphate buffer (pH 7) extract was reduced to 98.9% which indicated that E. telmateia could be a useful source of antioxidants with huge scavenger ability.     

First report of Hymenoscyphus fraxineus on Fraxinus excelsior in Montenegro

During the monitoring of the mycological complex on different forest tree species in the Biogradska Gora National Park in north‐east Montenegro, symptoms indicative of ash dieback caused by Hymenoscyphus fraxineus were observed on young Fraxinus excelsior trees in the protected virgin forest, including dieback of plants and branches, wilting of leaves and shoots leading to a “flag‐like” habitus, premature shedding of leaves and longitudinal bark necroses. Using standard isolation methods, slow‐growing cultures with numerous phialides, typical of the asexual phase of the ash dieback fungus, were obtained. In addition, petioles with numerous characteristic apothecia were also recorded. This is the first report of H. fraxineus on common ash in Montenegro. Possible pathways of introduction and implications of the findings are discussed.     

Parasitoid complex (Hymenoptera, Braconidae, Aphidiinae) of Aphis craccivora Koch (Hemiptera: Aphidoidea) in Iran

The parasitoids (Hymenoptera, Braconidae, Aphidiinae) of the cowpea aphid, Aphis craccivora Koch, were investigated throughout two far distant provinces, Tehran and Sistan-Baluchestan. Colonies of the cowpea aphid were collected from different host plants and reared under laboratory conditions until the parasitoids emerged. The aphids were parasitized by an expected range of parasitoids. The species were Aphidius colemani Viereck, Lysiphlebus fabarum (Marshall), Lysiphlebus confusus Tremblay and Eady, Lysiphlebus testaceipes (Cresson), Binodoxys acalephae (Marshall), Binodoxys angelicae (Haliday), Praon volucre (Haliday) and Ephedrus persicae Froggatt. L. testaceipes is reported here for the first time in Iran. The most common species was L. fabarum followed by B. acalephae and L. confusus. A key is provided for identification and host plant associations are considered.     

Evidence of scientific research on organic plant breeding: A bibliometric study

Use of varieties bred under organic conditions is essential in order to minimize the yield gap between organic and conventional agriculture. The aim of this study was to analyse research publications related to the topic ‘organic plant breeding’ from the Web of Science database using bibliometric science mapping and visualization tools. The number of analysed documents in the bibliographic dataset was 204 from the 53 sources. The overall trend in the organic plant breeding literature showed that the number of publications increased during the observed time-span. We found that in total, 65 countries and 337 institutions are active in the field of organic plant breeding with a high degree of international collaboration. The top five countries according to the number of publications were the United States, Italy, Germany, France, and Canada, while the most active institutions were Wageningen University, Iowa State University, University of Alberta, University of Copenhagen, and University of Hohenheim. All keywords from the organic plant breeding research in the agronomy category were separated into seven clusters for different research topics. Although there is evident progress viewed through the increased trend in the number of publications, organic plant breeding needs further expansion and development. This is especially through the implementation of novel plant breeding techniques and methods aiming to improve traits that are highly specific to organic conditions.     

Assessment of the retardation of selected herbicides onto Danube sediment based on small column tests

Journal of Soils and Sediments - This study utilizes column tests to investigate the retardation of certain herbicides with different hydrophobicities (atrazine, alachlor and trifluralin) during...     

Cabbage (Brassica oleracea var. capitata) as possible indicator of wartime metal and metalloid contamination in eastern Croatia (ICP-MS method)

Biomonitoring of the local population and environmental monitoring in eastern Croatia have revealed abnormalities in metal and metalloid distribution that could be related to war activities during the 1990s. The goal of this study was to determine whether there are differences in the concentrations of metals and metalloids by comparing locations of high and low-intensity combat activity; we also evaluated a possible connection between metal contamination in soil and in humans. We sampled 14 locations and measured the concentrations of 20 war related metals and metalloids (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Ni, Pb, Sb, Si, Sr, U, V and Zn). The results of principal components analysis showed two main clusters: locations Dopsin and Dalj (both characterized by high-intensity combat activity), where the concentrations of most elements (except Hg) were increased. Although the concentrations of metals and metalloids in cabbage samples collected in eastern Croatia did not exceed the maximum allowed values, the results of our study confirmed existance of environmental ‘hotspot’ with higher concentrations of war metals and metalloids. Our findings indicate that there is a possible common source and mechanism of transferring metals from the environment to the population.     

The Characterization of Heavy Metals in the Grapevine (Vitis vinifera) Cultivar Rkatsiteli and Wild Blackberry (Rubus fruticosus) from East Serbia by ICP-OES and BAFs

Inductively coupled plasma optical emission spectroscopy, in combination with calculation of various biological factors, was used in this study not only for a simple illustration of the present status of some essential and non-essential metals such as copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), arsenic (As), and cadmium (Cd) in the grapevine cultivar Rkatsiteli and wild blackberry from East Serbia but also for the estimation of plant bioaccumulation potentials. Great majority of detected metal concentrations were in normal ranges except in few cases: Zn concentrations were at the level of deficiency in almost all plant parts, and some Cu and As concentrations were at the levels that could be considered phytotoxic. Biological accumulation factors provided very informative data on metal accumulation and translocation in both plants and pointed to low accumulation rates of metals except in the case of Cu, Zn, and As in some wild blackberry tissues.     

Spatial and vertical distribution of <Superscript>137</Superscript>Cs in soils in the erosive area of southeastern Serbia (Pčinja and South Morava River Basins)

Purpose

The area of southeastern Serbia, the P?inja and South Morava River Basins, is under the influence of very strong erosion, and the aim of this study was to investigate the vertical and spatial distribution of the ¹³⁷Cs in the eroded soils of this area.

Materials and methods

Vertical soil profiles were collected with 5-cm increments from the uppermost layer down to 20, 25, 30, 40, and 50 cm of depth, depending on the thickness of the soil layers, i.e., down to the underlying parent rocks. Measurements of ¹³⁷Cs activity concentration were performed by using the HPGe gamma-ray spectrometer ORTEC-AMETEK (34 % relative efficiency and high resolution 1.65 keV at 1.33 MeV for ⁶⁰Co), from its gamma-ray line at 661.2 keV.

Results and discussion

The mean ¹³⁷Cs activity concentration across all 18 soil profiles (for all soil layers) was found to be 20 Bq kg^?1. In the greatest number of soil profiles, the ¹³⁷Cs activity concentration was generally highest in the first soil layer (0–5 cm) and decreased with soil depth, while in a few soil profiles, the peak of either the ¹³⁷Cs activity concentration occurred in the second soil layer (5–10 cm) or the ¹³⁷Cs activity concentration was almost equal throughout the entire soil profile. The mean ¹³⁷Cs activity concentration in the first soil layer (0–5 cm) was found to be 61 Bq kg^?1, and the high coefficient of variation of 92 % pointed out high spatial variability and large range of the ¹³⁷Cs activity concentrations in the study area.

Conclusions

The obtained results indicate that in the greatest number of soil profiles, ¹³⁷Cs is present in the upper layers, with concentration decreasing with depth, as is typical in uncultivated soil. Its spatial distribution was very uneven among the surface soil layers of the investigated sites. One of the main reasons for such pattern of ¹³⁷Cs in the study area may be soil erosion. Additional investigations which would support this hypothesis are required.

     

Principal component analysis of trace elements in Serbian wheat

Trace elements (Cu, Fe, Pb, Hg, Cd, As, Mn, Zn) were analyzed quantitatively in 14 wheat samples collected from fields in all Serbian growing regions, harvested in 2002. Microelements were determined according to an atomic absorption spectrophotometric method. Principal component analyses (PCA) were performed on data matrices consisting of contents of trace elements in wheats (columns) and all Serbian wheat-growing regions (rows). It was found that four principal components account for 87.2% of the total variance in the data. The plot of component loadings showed significant groupings for concentration of some microelements. The component scores indicated the similarities among the Serbian wheat-growing regions. The loading plot reveals that there is no need to measure all of the variables to achieve the same classification. It is enough to measure one variable per group. Naturally, this conclusion is valid only within the limits of the present study of wheat grain samples from different parts of Serbia.     

Oxidant/antioxidant properties of Croatian native propolis

Native propolis was defined as propolis powder collected from the continental part of Croatia and prepared according to a patented process that preserves all the propolis natural nutritional and organoleptic qualities. Nine phenolic compounds (out of thirteen tested) in propolis sample were detected by high performance liquid chromatography (HPLC) analysis. Among them chrysin was the most abundant (2478.5 microg/g propolis). Contrary to moderate antioxidant activity of propolis examined in vitro (ferric reduction antioxidant power; FRAP-assay), propolis as a food supplement modulated antioxidant enzymes (AOE) and significantly decreased lipid peroxidation processes (LPO) in plasma, liver, lungs, and brain of mice. The effect was dose- and tissue-dependent. The lower dose (100 mg/kg bw) protected plasma from oxidation, whereas the higher dose (300 mg/kg bw) was pro-oxidative. Hyperoxia (long-term normobaric 100% oxygen) increased LPO in all three organs tested. The highest vulnerability to oxidative stress was observed in lungs where hyperoxia was not associated with augmentation of AOE. Propolis protected lungs from hyperoxia by increased catalase (CAT) activity. This is of special importance for lungs since lungs of adult animals are highly vulnerable to oxidative stress because of their inability to augment AOE activity. Because of its strong antioxidant and scavenging abilities, native propolis might be used as a strong plant-based antioxidant effective not only in physiological conditions but also in cases that require prolonged high concentration of oxygen.