Boron Contents of Some Wild-Growing Mushrooms Collected from the Vicinity of Boron Mines in Balikesir,Turkey

The aim of the study was to determine the boron contents of some wild-growing mushrooms collected from the vicinity of several boron mines located in Balikesir, Turkey and compare the boron contents of some mushroom and soil samples. The locations of the mushroom samples collected were within the distance of 0–100, 100–500, and 500–1,000 m to the mines. Soil samples were taken from beneath randomly selected fungal fruit bodies. A total of 40 mushroom samples were found in the study area and 37 different species were identified. Among the 40 samples analyzed, the highest boron content was detected to be 273 mg kg⁻¹ in Suillus collinitus. Also, Tricholoma terreum (69.52 mg kg⁻¹), Myxomphalia maura (36.52 mg kg⁻¹), Otidea concinna (30.70 mg kg⁻¹), Sepultaria arenosa (28.94 mg kg⁻¹), Melanoleuca paedida (28.33 mg kg⁻¹), and Lycoperdon lividum (28.31 mg kg⁻¹) relatively have high levels of boron and these species are proposed as candidates for boron accumulation. The boron contents of the other mushrooms varied and a pattern was observed where the boron content was found to be decreased as the distance from the mines increased.     

Permissible Value for Vanadium in Allitic Udic Ferrisols Based on Physiological Responses of Green Chinese Cabbage and Soil Microbes

Greenhouse experiments were conducted to study the permissible value of vanadium (V) based on the growth and physiological responses of green Chinese cabbage (Brassica chinensis L.), and effects of V on microbial biomass carbon (MBC) and enzyme activities in allitic udic ferrisols were also studied. The results showed that biomass of cabbage grown on soil treated with 133 mg V kg⁻¹ significantly decreased by 25.1% compared with the control (P < 0.05). Vanadium concentrations in leaves and roots increased with increasing soil V concentration. Contents of vitamin C (Vc) increased by 10.3%, while that of soluble sugar in leaves significantly decreased by 54.0% when soil V concentration was 133 mg kg⁻¹, respectively. The uptake of essential nutrient elements by cabbage was disturbed when soil V concentration exceeded 253 mg kg⁻¹. Soil MBC was significantly stimulated by 15.5%, while dehydrogenase activity significantly decreased by 62.8% and urease activity slightly changed at treatment of 133 mg V kg⁻¹ as compared with the control, respectively. Therefore, the permissible value of V in allitic udic ferrisols is proposed as 130 mg kg⁻¹.     

Major and Trace Elements in Zooplankton from the Northern Gulf of California During Summer

We report the distribution of major and trace element concentrations in epipelagic zooplankton collected in the Northern Gulf of California in August 2003. The Bray–Curtis index defined three element assemblages in zooplankton: (1) major metals, which included only two elements, Na (3.6–17.0%) and Ca (1.0–4.8%). Na had its highest concentrations in the shallow tidally mixed Upper Gulf, where high salinity, temperature, and zooplankton biomass (dominated by copepods) prevailed. Ca showed its highest concentrations south of Ballenas Channel, characterized by tidal mixing and convergence-induced upwelling, indicated by low sea-surface temperature, salinity, and zooplankton biomass; (2) Six biological essential elements, like Fe (80–9,100 mg kg⁻¹) and Zn (20–2,570 mg kg⁻¹), were detected in high concentrations in zooplankton collected near Guaymas Basin, which had high surface temperature and chlorophyll a concentrations. (3) Metals of terrigenous origin, such as Sc (0.01–1.4 mg kg⁻¹) and Th (0.03–2.3 mg kg⁻¹), and redox-sensitive metals, like Co (3–23.8 mg kg⁻¹); this was the assemblage with the largest number of elements (15). Both types of elements of assemblage 3 had maximum concentrations in the cyclonic eddy that dominates the summer circulation in the Northern region. We concluded that sediment resuspension by tidal mixing in the Upper Gulf, upwelling south of Ballenas Channel, and the cyclonic eddy were key oceanographic features that affected the element concentrations of epipelagic zooplankton in the Northern Gulf of California. Oceanographic mechanisms such as these may contribute to element incorporation in marine organisms in other seas.     

Sulphur protects mustard (<Emphasis Type="Italic">Brassica campestris</Emphasis> L.) from cadmium toxicity by improving leaf ascorbate and glutathione

In a pot-soil culture ameliorative effect of sulphur (S) (0 or 40 mg S kg⁻¹ soil) on cadmium (Cd) (0, 25, 50 and 100 mg Cd kg⁻¹ soil)-induced growth inhibition and oxidative stress in mustard (Brassica campestris L.) cultivar Pusa Gold was studied. Cadmium at 100 mg kg⁻¹ soil caused maximum increase in the contents of Cd and thiobarbituric acid reactive substances (TBARS) in leaves. Maximum reductions in growth (plant dry mass, leaf area), chlorophyll content, net photosynthetic rate (P_N) and the contents of ascorbate (AsA), glutathione (GSH) were observed with 100 mg Cd kg⁻¹ soil compared to control. The application of S helped in reducing Cd toxicity, which was greater for 25 and 50 mg Cd kg⁻¹ soil) compared to 100 mg Cd kg⁻¹ soil. Addition of S to Cd-treated plants showed decrease in Cd and TBARS content in leaves and restoration of growth and photosynthesis through increase in the contents of AsA and GSH. Net photosynthetic rate and plant dry mass were strongly and positively correlated with the contents of AsA and GSH. It is suggested that S may ameliorate Cd toxicity and protects growth and photosynthesis of mustard involving AsA and GSH.     

Responses of Wheat Roots to Exogenous Selenium Supply Under Enhanced Ultraviolet-B

Effects of selenium (Se) on growth and some physiological traits of roots in wheat (Triticum aestivum L. cv Han NO.7086) seedlings exposed to enhanced ultraviolet-B (UV-B) stress are reported. Responses of roots were different depending on the Se concentration. Compared with the control, root weight of wheat seedlings treated with 1.0 and 2.0 mg Se kg⁻¹ soil increased by 39.47% and 16.28%, respectively. The lower amount Se (0.5 mg kg⁻¹) and the higher amount Se treatments (3.0 mg kg⁻¹) did not significantly affect on root weight. Se treatments significantly increased root activity, flavonoids and proline content, and activities of peroxidase and superoxide dimutase in wheat roots exposed to enhanced UV-B. In addition, the treatments with 0.5, 1.0, and 2.0 mg Se kg⁻¹ significantly reduced malondialdehyde content and the rate of superoxide radical (O₂⁻) production of roots, whereas the higher amount Se treatment only induced a decrease in the rate of O₂⁻ production. The results of this study demonstrated that optimal Se supply promoted roots growth of wheat seedlings, and that optimal Se supply could reduce oxidative stress in wheat roots under enhanced UV-B radiation.     

Fungal diversity and natural occurrence of fusaproliferin,beauvericin, deoxynivalenol and nivalenol in wheat cultivated in Santa Fe Province,Argentina

The Fusarium diversity and the mycobiota associated with moldy wheat kernels from Santa Fe province, Argentine, was assessed. The wheat cultivated area in Santa Fe province is divided according to agrometeorological conditions into two zones: Zone I (north-central) and Zone II (south). The natural occurrence of Fusarium toxins BEA, FUP, DON and NIV was also determined. Cladosporium was the most abundant of the 19 genera identified, followed by Fusarium, Phoma and Alternaria. Zone II shows a predominance of F. graminearum and F. culmorum. In Zone I, DON was present in 13/32 samples (range 0.43–3.60 mg kg⁻¹) and NIV in 6/32 samples (range 0.11–0.40 mg kg⁻¹). In zone II, DON was found in 11/21 samples (range 0.57–9.50 mg kg⁻¹) and NIV in 4/21 samples (range 0.10–0.60 mg kg⁻¹). BEA and FP were not detected in both zones.     

Silicate-Mediated Alleviation of Pb Toxicity in Banana Grown in Pb-Contaminated Soil

Silicate (Si) can enhance plant resistance or tolerance to the toxicity of heavy metals. However, it remains unclear whether Si can ameliorate lead (Pb) toxicity in banana (Musa xparadisiaca) roots. In this study, treatment with 800 mg kg⁻¹ Pb decreased both the shoot and root weight of banana seedlings. The amendment of 800 mg kg⁻¹ Si (sodium metasilicate, Na₂SiO₃·9H₂O) to the Pb-contaminated soil enhanced banana biomass at two growth stages significantly. The amendment of 800 mg kg⁻¹ Si significantly increased soil pH and decreased exchangeable Pb, thus reducing soil Pb availability, while Si addition of 100 mg kg⁻¹ did not influence soil pH. Results from Pb fractionation analysis indicated that more Pb were in the form of carbonate and residual-bound fractions in the Si-amended Pb-contaminated soils. The ratio of Pb-bound carbonate to the total Pb tended to increase with increasing growth stages. Treatment with 100 mg kg⁻¹ Si had smaller effects on Pb forms in the Si-amended soils than that of 800 mg kg⁻¹ Si. Pb treatment decreased the xylem sap greatly, but the addition of Si at both levels increased xylem sap and reduced Pb concentration in xylem sap significantly in the Si-amended Pb treatments. The addition of Si increased the activities of POD, SOD, and CAT in banana roots by 14.2% to 72.1% in the Si-amended Pb treatments. The results suggested that Si-enhanced tolerance to Pb toxicity in banana seedlings was associated with Pb immobilization in the soils, the decrease of Pb transport from roots to shoots, and Si-mediated detoxification of Pb in the plants.     

Biomass production and nutrient accumulation in <Emphasis Type="Italic">Sparganium emersum</Emphasis> Rehm. after sediment treatment with mineral and organic fertilisers in three mesocosm experiments

The response of the aquatic plant Sparganium emersum to different sediment nutrient levels was studied in three mesocosm experiments. The aim was to assess plant growth parameters and nutrient accumulation in the plant tissue under conditions relevant for habitats with sediments affected by anthropogenic nutrient enrichment. The experimental treatments were produced by fertilisation of the rooting medium (washed river sand) with differing doses of either NPK mineral fertiliser or digested sludge from solid pig slurry waste. Growth inhibition by high nutrient levels was not observed in any treatment (highest nutrient concentrations in the sediment with mineral fertiliser: N 250 mg kg⁻¹, P 50 mg kg⁻¹; organic fertiliser: N 6300 mg kg⁻¹, P 1800 mg kg⁻¹), which confirms the tolerance of S. emersum to high nutrient loads. The sediment nutrient concentration was best reflected in shoot dry mass. Nutrient contents in plant tissues were similar for most nutrient concentrations in the rooting media; only N increased significantly with N levels in the sediment in belowground parts. Nutrient standing stocks in plants, however, generally corresponded to the nutrient supply, and reached highest values (max. N 3.7 g m⁻², P 1.2 g m⁻²) in the richest treatments with organic fertiliser. The capability of S. emersum to use nutrients from high sediment concentrations and in organically polluted environments recommends this species for use in water quality management including tertiary wastewater treatment.     

Responses of Wheat Seedlings to Exogenous Selenium Supply Under Cold Stress

Dose-dependent effects of selenium on growth and physiological trait of wheat seedlings (Triticum aestivum L. cv Han NO.7086) exposed to cold stress are reported. Responses of seedlings were different depending on the Se concentration. The treatments with 0.5 and 1.0 mg Se kg⁻¹ significantly increased biomass and chlorophyll content of seedlings. However, the treatments at 2.0 and 3.0 mg Se kg⁻¹ only induced an evident increase in chlorophyll content and did not promote biomass accumulation of seedlings. Antioxidant compounds content (anthocyanins, flavonoids, and phenolic compounds) and antioxidant enzymes’ activities (peroxidase and catalase) increased by different Se treatments, while only the treatment with 1.0 mg Se kg⁻¹ induced a significant reduce in malondialdehyde content and the rate of superoxide radical production of wheat seedlings. The results of this study demonstrated that Se supply could increase antioxidant capacity of seedlings, and optimal Se supply reduced production of free radicals, membrane lipid peroxidation, and promoted biomass accumulation.     

Boron and other elements in sporophores of ectomycorrhizal and saprotrophic fungi

Fungi are usually thought not to have a boron (B) requirement. It is not known if mycorrhizas take up B from low concentrations that are common in forest soils, as fungi might also immobilise B. Here, we studied the B concentrations in sporophores of 49 ectomycorrhizal and 10 saprotrophic fungi to assess whether B is translocated in mycelium or not. Additionally, P and metal concentrations were measured for comparison. Variability both within species and between species was very large, as the lowest measured B concentration was 0.01 mg kg⁻¹ in Amanita muscaria, and the highest was 280 mg kg⁻¹ in Paxillus involutus. There was no clear difference between saprotrophic and mycorrhizal fungi. The majority of species did not accumulate B at more than 0.01–3 mg kg⁻¹, but there were some species that consistently had median concentration values higher than 5–6 mg kg⁻¹ and much higher maximum values, particularly Paxillus involutus, Lactarius necator and several Russula species. Most species increased their B concentration in B fertilised plots, but there were exceptions, particularly Rozites caperatus and Lactarius camphoratus. Boron concentrations did not correlate with those of other elements. In conclusion, B is translocated in the mycelia of most of the studied species. The differences between species may be due to differences in their water use, or carbohydrates used in translocation. It remains to be studied, if B concentrations in mycorrhizas or mycelia in soil are in the same order of magnitude as the larger ones found here, and if this has any effects on the host plants.     

In vitro degradation of zearalenone by Bacillus subtilis

Zearalenone (ZEN) is a non-steroidal estrogen produced by many Fusarium species in cereals and other plants, and is frequently implicated in safety of foods and feeds. A ZEN-degrading microorganism has been isolated and identified as a Bacillus subtilis subspecies. It degraded 99% ZEN (1 mg kg⁻¹) in liquid medium after 24 h and more than 95% of ZEN (0.25 mg kg⁻¹) could be degraded after 48 h in a solid-state fermentation. This isolate can thus be used to decontaminate raw materials, like grains, to reduce the mycotoxin concentration.     

Cardiovascular control via angiotensin II and circulating catecholamines in the spiny dogfish, Squalus acanthias

The contributions of circulating angiotensin II (Ang II) and catecholamines to cardiovascular control in the spiny dogfish were investigated by monitoring the effects of exogenous and endogenous dogfish [Asn¹, Pro³, Ile⁵]-Ang II (dfAng II) on plasma catecholamine levels and blood pressure regulation. Bolus intravenous injections of dfAng II (30–1200 pmol kg⁻¹) elicited dose-dependent increases in plasma adrenaline and noradrenaline concentrations, caudal artery pressure (P _CA), and systemic vascular resistance (R _S), and a decrease in cardiac output (Q). Similar injections of Ang II in dogfish pre-treated with the α-adrenoceptor antagonist yohimbine (4 mg kg⁻¹) also elicited dose-dependent increases in plasma catecholamine levels yet the cardiovascular effects were abolished. Dogfish treated with yohimbine were hypotensive and had elevated levels of plasma Ang II and catecholamines. Intravenous injection of the smooth muscle relaxant papaverine (10 mg kg⁻¹) elicited a transient decrease in P _CA and R _S, and increases in plasma Ang II and catecholamine levels. In dogfish first treated with lisinopril (10⁻⁴ mol kg⁻¹), an angiotensin converting enzyme inhibitor, papaverine treatment caused a more prolonged and greater decrease in P _CA and R _S, an attenuated increase in plasma catecholamines, and no change in plasma Ang II. By itself, lisinopril treatment had little effect on P _CA, and no effect on R _S, plasma Ang II or catecholamines. In yohimbine-treated dogfish, papaverine treatment elicited marked decreases in P _CA, R _S, and Q, and increases in plasma Ang II and catecholamines. Among the three papaverine treatments, there was a positive linear relationship between plasma Ang II and catecholamine concentrations, and the cardiovascular and hormonal changes were most pronounced in the yohimbine + papaverine treatment. Therefore, under resting normotensive conditions, while Ang II does not appear to be involved in cardiovascular control, catecholamines play an important role. However, during a hypotensive stress elicited by vascular smooth muscle relaxation, Ang II indirectly contributes to cardiovascular control by dose-dependently stimulating catecholamine release. Accepted: 24 February 1999     

Response of methanotrophs and methane oxidation on ammonium application in landfill soils

To test the dose effect of ammonium (NH₄ ⁺) fertilization on soil methane (CH₄) oxidation by methanotrophic communities, batch incubations were conducted at a wide scale of NH₄ ⁺ amendments: 0, 100, 250, 500, and 1,000 mg N kg_dry soil ⁻¹. Denaturing gradient gel electrophoresis and real-time quantitative PCR analysis were conducted to investigate the correlation between the CH₄ oxidation capacity and methanotrophic communities. Immediately after the addition of NH₄ ⁺, temporal inhibition of CH₄ oxidation occurred, and this might have been due to the non-specific salt effect (osmotic stress). After a lag phase, the CH₄ oxidation rates of the soils with NH₄ ⁺ fertilization were promoted to levels higher than those of the controls. More than 100 mg N kg_dry soil ⁻¹ of NH₄ ⁺ addition resulted in the reduction of type II/type I MOB ratios and an obvious evolution of type II MOB communities, while less than 100 mg N kg_dry soil ⁻¹ of NH₄ ⁺ addition induced nearly no change of methanotrophic community compositions. The NH₄ ⁺-derived stimulation after the lag phase was attributed to the improvement of N availability for type I MOB. Compared with the controls, 100 mg N kg_dry soil ⁻¹ of NH₄ ⁺ addition doubled the CH₄ oxidation peak value to more than 20 mg CH₄ kg_dry soil ⁻¹ h⁻¹. Therefore, an appropriate amount of leachate irrigation on the landfill cover layer might efficiently mitigate the CH₄ emissions.     

Accumulation and Speciation of Selenium in Plants as Affected by Arbuscular Mycorrhizal Fungus <Emphasis Type="BoldItalic">Glomus mosseae</Emphasis>

Effects of arbuscular mycorrhizal fungus (Glomus mosseae) on the accumulation and speciation of selenium (Se) in alfalfa, maize, and soybean were investigated by using Se(IV)-spiked soil. Mycorrhizal inoculation decreased Se accumulation in roots and shoots of all the plants at Se spiked level of 0 or 2 mg kg⁻¹, while an increased Se accumulation was observed in alfalfa shoots and maize roots and shoots at the spiked level of 20 mg kg⁻¹. Concentration of inorganic Se (especially Se(VI)) in roots and shoots of the three plants was much higher in mycorrhizal than non-mycorrhizal treatment. Mycorrhizal inoculation decreased the portion of total organic Se in plant tissues with the exception of alfalfa and maize shoots at Se spiked level of 20 mg kg⁻¹, in which organic Se portion did not reduced greatly (<5%) for mycorrhizal treatment. Mycorrhizal effects on alfalfa and maize were more obvious than on soybean in terms of root colonization rate, biomass, and Se accumulation.     

Fluoranthene-induced production of ethylene and formation of lysigenous intercellular spaces in pea plants cultivated in vitro

The effect of increasing concentration of polycyclic aromatic hydrocarbon (PAH) fluoranthene (FLT; 0.1, 1 and 5 mg l⁻¹) on the growth, ethylene production and anatomy of stems of 21-day-old pea plants cultivated in vitro in MS medium, with or without FLT, enriched with 0.1 mg l⁻¹ indole-3-acetic acid (IAA) or with combination of 0.1 mg l⁻¹ IAA + 0.1 mg l⁻¹ N⁶-benzyladenine (BA) were investigated. The low concentration of 0.1 mg l⁻¹ FLT, in both IAA- and IAA + BA-treated plants, significantly stimulated the growth of pea callus, while higher concentrations 1 mg l⁻¹ and especially 5 mg l⁻¹ FLT significantly inhibited it. Pea shoots were significantly influenced only after application of 5 mg l⁻¹ FLT in IAA treatment. Significantly increased production of ethylene was found in IAA + BA treatments in all concentrations of FLT, whereas in IAA treatments in 1 and 5 mg l⁻¹ FLT. The lysigenous aerenchyma formation in the cortex of pea stems significantly increased in all FLT treatments and its highest proportion was found in plants exposed to 1 mg l⁻¹ FLT.     

The effect of thidiazuron level on in vitro regeneration type and peroxidase profile in <Emphasis Type="Italic">Eucalyptus microtheca</Emphasis> F. Muell

The green twigs of 1-year-old Eucalyptus microtheca F. Muell seedlings were cultured on modified MS medium, supplemented with α-naphthalene acetic acid (NAA) and kinetin (Kin) hormones at 12 different concentrations. After 4 weeks, the combination of 1 mg l⁻¹ NAA + 1 mg l⁻¹ Kin induced the highest number of axillary shoots. Meanwhile, embryogenic calli were observed in media containing 4 mg l⁻¹ NAA + 0.5 mg l⁻¹ Kin, without any regeneration. The hormone treatments were followed by subculturing the twigs in different levels of thidiazuron (TDZ). The combination of 1 mg l⁻¹ NAA + 1 mg l⁻¹ Kin together with 0.01 mg l⁻¹ TDZ resulted in an increase of direct shoot, while higher amounts of TDZ led to adventitious shoot induction. Somatic embryogenesis was observed in the treatment containing 0.01 mg l⁻¹ TDZ + 4 mg l⁻¹ NAA + 0.5 mg l⁻¹Kin. The peroxidase (POD) band patterns in regenerated plantlets were investigated in order to determine the effect of different levels of TDZ on loci synthesis. A dimer locus, a tetramer locus and two epigenetic bands (a new band for NAA + Kin and the other for TDZ) were observed in the POD profiles. In case of low (0.01 mg l⁻¹ and 0.1 mg l⁻¹) levels of TDZ, one heterozygote allele was disappeared from dimer locus, while at higher TDZ levels, the dimer locus lost its stability and tetramer locus showed a high activity. Thus, POD allele patterns seems to be a feasible marker for different types of regeneration.     

Inhibitory effect of curcumin on liver injury in a murine model of endotoxemic shock

The effect of curcumin on lipopolysaccharide/d-galactosamine (LPS/GalN)-induced acute shock model of liver injury was examined in mice. The simultaneous administration of LPS (5–20 μg kg⁻¹, i.p.) and GalN (700 mg kg⁻¹, i.p.) markedly increased the serum tumor necrosis factor-α (TNF-α), glutamic oxaloacetic transaminase/glutamic pyruvic transaminase (GOT/GPT), and massive hepatic necrosis and inflammation, leading to 100% lethality. Pre-administration of curcumin (100 mg kg⁻¹, i.p.) 3 h before induction with LPS/GalN imparted a large extent of protection against acute elevation in serum TNF-α and serum GOT/GPT. Hepatic necrosis and lethality caused by LPS/GalN was also greatly reduced by curcumin treatment. The results demonstrated that curcumin could protect mice from LPS/GalN-induced hepatic injury and inflammation through blockading TNF-α production, eventually raising the survival rate of septic-shock-induced mice.     

Vanadium Uptake by Alfalfa Grown in V–Cd-Contaminated Soil by Pot Experiment

In order to characterize uptake of vanadium in alfalfa grown in vanadium–cadmium (Cd)-contaminated soil, 104 soil samples and 94 plant samples were collected from pot experiment. The results showed alfalfa had strong metal adaptability (up to 400 mg kg⁻¹) and high accumulation (up to 3,440.14 mg kg⁻¹) of vanadium. Root had higher contents and better absorption to vanadium than overground part. Moreover, both root and overground part had direct correlation with vanadium in soil, especially with the sum of first three fractions and reducible fraction. With the increasing of vanadium, higher concentration of Cd may inhibit the absorption of vanadium in alfalfa.