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91.
Foliar-applied glyphosate substantially reduced uptake and transport of iron and manganese in sunflower (Helianthus annuus L.) plants 总被引:1,自引:0,他引:1
Eker S Ozturk L Yazici A Erenoglu B Romheld V Cakmak I 《Journal of agricultural and food chemistry》2006,54(26):10019-10025
Evidence clearly shows that cationic micronutrients in spray solutions reduce the herbicidal effectiveness of glyphosate for weed control due to the formation of metal-glyphosate complexes. The formation of these glyphosate-metal complexes in plant tissue may also impair micronutrient nutrition of nontarget plants when exposed to glyphosate drift or glyphosate residues in soil. In the present study, the effects of simulated glyphosate drift on plant growth and uptake, translocation, and accumulation (tissue concentration) of iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were investigated in sunflower (Helianthus annuus L.) plants grown in nutrient solution under controlled environmental conditions. Glyphosate was sprayed on plant shoots at different rates between 1.25 and 6.0% of the recommended dosage (i.e., 0.39 and 1.89 mM glyphosate isopropylamine salt). Glyphosate applications significantly decreased root and shoot dry matter production and chlorophyll concentrations of young leaves and shoot tips. The basal parts of the youngest leaves and shoot tips were severely chlorotic. These effects became apparent within 48 h after the glyphosate spray. Glyphosate also caused substantial decreases in leaf concentration of Fe and Mn while the concentration of Zn and Cu was less affected. In short-term uptake experiments with radiolabeled Fe (59Fe), Mn (54Mn), and Zn (65Zn), root uptake of 59Fe and 54Mn was significantly reduced in 12 and 24 h after application of 6% of the recommended dosage of glyphosate, respectively. Glyphosate resulted in almost complete inhibition of root-to-shoot translocation of 59Fe within 12 h and 54Mn within 24 h after application. These results suggest that glyphosate residues or drift may result in severe impairments in Fe and Mn nutrition of nontarget plants, possibly due to the formation of poorly soluble glyphosate-metal complexes in plant tissues and/or rhizosphere interactions. 相似文献
92.
In this study, the ages of 76 individuals belonging to the Cyprinion macrostomus (Heckel, 1843) population caught from Murat River near Bingöl city were determined from six different bony structures and the level of calcium mineral of each bony structure was measured using an atomic absorption spectrophotometer. The determined element was statistically examined according to the age, length, weight and sex of the fish. The age, length and weight ranges of the fish were found to be 2–6, 12.0–21.2 mm and 16.3–135.3 g respectively. The relationships between the accumulation of calcium in all bony structures and the fish size (both length and weight) were found to be insignificant (P>0.05). However, a strong relationship was found between fish weight and accumulation of the mineral in vertebra and otolith. A strong correlation was also found between fish length and accumulation of calcium in the dorsal fin ray, followed by the otolith, vertebra and cleithrum bones respectively. Whereas the accumulation of calcium according to the age groups was found to be insignificant for scale and operculum (P>0.05), it was found to be significant for all the other bony structures examined (P<0.05). In conclusion, the accumulation of calcium on some bony structures of C. macrostomus was observed to increase with an increase in age, length and weight of fish, although the increases were not statistically significant at least for some bony structures (P>0.05). 相似文献
93.
Kleigrewe K Aydin F Hogrefe K Piecuch P Bergander K Würthwein EU Humpf HU 《Journal of agricultural and food chemistry》2012,60(21):5497-5505
Fusarin C is a Fusarium mycotoxin that rearranges under reversed phase chromatographic conditions. In this study, the rearrangement of fusarin C was examined in detail, and the formation of fusarins under different conditions was optimized. All relevant fusarins including (10Z)-, (8Z)-, and (6Z)-fusarin C were isolated and identified by NMR. To confirm the involvement of the 2-pyrrolidone ring in the rearrangement of fusarin C, 15-methoxy-fusarin C was synthesized. For the first time, the structure of open-chain fusarin C was elucidated, and on the basis of these data, the rearrangement product of fusarin C was identified as epi-fusarin C. The results were confirmed by detailed NMR measurements and density functional theory calculations. Furthermore, a new fusarin C like metabolite, which was named dihydrofusarin C, was detected by analysis of the crude extract of fusarin C with high-performance liquid chromatography coupled to UV and Fourier transform mass spectrometry. 相似文献
94.
Effect of Silicon on Plant Growth and Mineral Nutrition of Maize Grown Under Water-Stress Conditions
The effect of silicon (Si) on physiological attributes and nutritional status of maize (Zea mays cv. DK 647 F1) under water stress was studied in a pot experiment. Treatments were (1) well watered (WW): 100% of FC (soil field capacity), (2) WW + Si1: 100% of FC + 1 mM Si, (3) WW + Si2: 100% of FC + 2 mM Si, (4) water stress (WS): 50% of FC, (5) WS + Si1: 50% of FC + 1 mM Si and (6) WS + Si2: 50% of FC + 2 mM Si. In the control treatment, plants were irrigated to field capacity (100% FC). Water stress was imposed by maintaining a moisture level equivalent to 50% of field capacity, whereas the well-watered pots (control) were maintained at full field capacity. Water stress was found to reduce the total dry matter (DM), chlorophyll content, and relative water content (RWC), but to increase proline accumulation and electrolyte leakage in maize plants. Both Si treatments largely improved the above physiological parameters, but levels remained significantly lower than the control (WW) values except for electrolyte leakage and root:shoot ratios, which were higher. Only root DM appeared to show very little variation in any of the treatments. The concentration of Si in the plants was increased by Si addition into the nutrient solution. Water stress reduced leaf calcium (Ca) and potassium (K) of maize plants, but addition of Si increased these nutrient levels; Ca levels were similar to WW under the high-Si treatment, but K was lower. Root Ca and K were both increased by WS; root Ca was further increased by high Si (WS + Si2 treatment). Addition of Si to the WS treatments did not change root K. Results indicate that while application of Si may be one approach to improve growth of this crop and increase its production in arid or semi-arid areas where water is at a premium, this technique would not fully substitute for an adequate water supply. 相似文献
95.
Cengiz Kaya A. Levent Tuna Murat Guneri Muhammed Ashraf 《Journal of plant nutrition》2013,36(13):1985-1994
Interactive effects of silicon (Si) and high boron (B) on growth and yield of tomato (Lycopercison esculentum cv. ‘191 F1’) plants were studied. Treatments were: 1) control (B1), normal nutrient solution including 0.5 mg L?1 B (boron), 2) B1 +Si treatment: 0.5 mg L?1 boron plus 2 mM Si, 3) B2 treatment: 3.5 mg L?1 B, 4) B2 +Si treatment: 3.5 mg L?1 B plus 2 mM Si, 5) B3 treatment: 6.5 mg L?1 B, and 6) B3 +Si: 6.5 mg L?1 B plus 2 mM Si. High B reduced dry matter, fruit yield and chlorophyll (Chl) in tomato plants compared to the control treatment, but increased the proline accumulation. Supplementary Si overcame the deleterious effects of high B on plant dry matter, fruit yield and chlorophyll concentrations. High B treatments increased the activities of superoxide dismutase (SOD; EC 1.15.1.1), peroxidase (POD; EC. 1.11.1.7) and polyphenol oxidase (PPO; EC 1.10.3.1). However, supplementary Si in the nutrient solution containing high B reduced SOD and PPO activities in leaves, but POD activity remained unchanged. These data suggest that excess B-induced oxidative stress and alterations in the antioxidant enzymes. Boron (B) concentrations increased in leaves and roots in the elevated B treatment as compared to the control treatment. Concentrations of calcium (Ca) and potassium (K) were significantly lower in the leaves of plants grown at high B than those in the control plants. Supplementing the nutrient solution containing high B with 2 mM Si increased both nutrients in the leaves. These results indicate that supplementary Si can mitigate the adverse effects of high B on fruit yield and whole plant biomass in tomato plants. 相似文献
96.
Aydin Akin Alper Dardeniz Fadime Ates Mustafa Celik 《Journal of plant nutrition》2013,36(13):1949-1957
Crop loads and leaf fertilizers are highly important for yield and quality of grapevine. This research was conducted in the Konya province of Turkey in 2008 and 2009. The effects of crop loads and leaf fertilizers were investigated on yield and quality of Vitis vinifera L. cv. ‘Gök üzüm’. The combined leaf fertilizer (TAR??-ZF) significantly increased quality parameters such as berry length, berry weight, maturity index, juice yield and drying index of grapevine. Increasing crop load values (16, 21, and 26 buds/vine) increased fresh grape yield and juice yield; however, maturity index and drying index decreased in comparison to the control. According to these results, it was suggested that to produce a high yield 26 buds/vine pruning and non-fertilization could be utilized or to increase quality parameters 16 buds/vine pruning, and fertilization may be applied on grapevine cultivation. 相似文献
97.
Aydin Gunes Wietse N. K. Post Ernest A. Kirkby Mehmet Aktas 《Journal of plant nutrition》2013,36(11):1929-1938
Two cultivars of lettuce plants (Lactuca sativa L. cvs Berlo and Kirsten) were grown for two months in late fall in NFT under three different nitrogen (N)‐regimes but with the same total N concentration (13.4 mM). A reference treatment with a nutrient solution containing 94% nitrate (NO3) and 6% ammonium (NH4) was compared with urea and proteinate treatments in which 20% of the NO3 of the reference treatment was replaced by either of these two N sources. Proteinate is a fertilizer produced in Turkey containing 8% amino acid N and 8% NO3‐N. For both cultivars the fresh weights of the harvested plants were unaffected by the N source as was also the total N uptake. Nitrate content, however, was considerably lower in the urea and proteinate plants, values for the three treatments ranging from 3314 to 4579 mg NO3/kg fresh wt making up from between 44.3% to 55.4% of the total plant N. Of the two cultivars, Berlo accumulated greater concentrations of NO3 than did Kirsten. The accumulation of chloride (Cl) was in the reverse order of that of NO3 with greatest concentrations occurring in the proteinate plants. 相似文献
98.
Angora rabbit fibre is one of the finest specialty animal fibres with its well-known reputation for fineness, lightness and
softness. This study evaluated the Angora fibre shape and morphology in comparison with Cashmere fibre and wool as well as
the relation between characteristics of Angora fibre. Unlike other keratinous textile fibres, single Angora fibre composes
of two sections named as body and head, each of which has individual surface characteristics. Differences between the scale
shapes, scale length and scale frequency of Angora hair types were explained in details. Medullation in Angora fibre was explained
for different types of Angora hairs defined as down, awn and bristle. This classification was done according to the fibre
fineness starting from the finer one. Relation between fibre shape and comfort factor was also analyzed. The relation between
mean fibre diameter (MFD), fibre curvature (FC) and percentage of medullation by volume (MEDV) for Angora rabbit fibre was
not as strong as wool and Cashmere fibre. Accordingly, when Angora hair types were analyzed individually, it was observed
that relation between FC and MEDV for Angora fibre was stronger than wool and Cashmere fibre. Multiple regression analysis
was also performed. Diameter distribution along the snippet length (about 200μm) of Angora fibre is uneven compared to Cashmere fibre and wool. 相似文献
99.
Selami Demir Arslan Saral Ferruh Ertürk Levent Kuzu 《Water, air, and soil pollution》2010,212(1-4):429-439
Chemical mass balance (CMB) and principal component analysis (PCA) are used together for source identification and source apportionment in this air pollution modeling study. Source profile sets, each of which contains five source profiles based on ten pollutant species, were generated using a computer program. Another algorithm was implemented to produce ten random data sets, which was composed of 100 simulated measurement results for all of ten pollutant species. Ten source profile sets were selected. Five of them contained sources of dissimilar characteristics, whereas the other five were chosen from those of similar emission profiles. Ten simulated data sets for each source profile set were used in the analyses. PCA was applied to all simulated data sets; a number of principal factors were extracted and interpreted. The identified sources for each data set were used in fitting with CMB analyses, and source contributions were estimated. The performance of PCA–CMB combination was evaluated in the aspect of percent variance explained, percent apportionment, R 2, and χ 2. PCA was able to explain 89.6% to 100% of the variance within the data sets used. Two to five sources were extracted depending on the characteristics of source profile sets used. CMB was found to be successful in the aspect of percent apportionment since 95.4% to 100% of mass concentrations were apportioned. The values of R 2 and χ 2 were found out to range from 0.981 to 1.000 and from 0.000 to 29.947, respectively. Evaluating overall results from the analyses, PCA–CMB combination produced satisfactory results in the aspect of source identification and source apportionment. 相似文献
100.
Multivariate Statistical Techniques for the Assessment of Surface Water Quality at the Mid-Black Sea Coast of Turkey 总被引:1,自引:0,他引:1
Feryal Akbal Levent G��rel Tolga Bahad?r ?lknur G��ler G��lfem Bakan Hanife B��y��kg��ng?r 《Water, air, and soil pollution》2011,216(1-4):21-37
The aim of this study was to investigate the seasonal and spatial variations in surface water quality at the mid-Black Sea coast of Turkey. The samples were collected from ten monitoring stations including rivers and sea water during the years from 2007 to 2008. The samples were analyzed for 25 parameters: total carbon, total inorganic carbon, total organic carbon, chromium, cadmium, copper, lead, iron, nickel, manganese, phenol, surfactants, ammonium, nitrite and nitrate-nitrogen, total phosphorus, adsorbable organic halogen, sulfate, hardness, dissolved oxygen, pH, temperature, total dissolved solids, electrical conductivity, and salinity. Multivariate statistical techniques, cluster analysis (CA) and factor analysis/principal component analysis (FA/PCA), were applied to analyze the similarities among the sampling sites to identify the source apportionment of pollution parameters in surface waters. The results indicate that seven factors for river water explained 82.24% of the variance. In seawater, seven factors account for 89.65% of the total variance. Varifactors obtained from factor analysis indicate that the parameters responsible for water quality variations are mainly related to organic pollution (municipal effluents), inorganic pollution (industrial effluents and waste disposal areas), nutrients (agricultural runoff), and dissolved salts (soil leaching and runoff process). 相似文献