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111.
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Chlorantraniliprole, an anthranilic diamide insecticide with novel mode of action, is found effective against several lepidopteran as well as coleopteran, dipteran, and hemipteran pests. The present studies were carried out to study the persistence pattern of chlorantraniliprole on sugarcane field soil following application of granule formulation. The residues of chlorantraniliprole were estimated using high performance liquid chromatograph (HPLC) and confirmed by liquid chromatograph-mass spectrometry (LC-MS/MS). Following application of chlorantraniliprole (Ferterra 0.4G) at 100 and 200 g a.i. ha?1, the average initial deposits of chlorantraniliprole were observed to be 0.88 and 1.59 mg kg?1, respectively. These residues dissipated below the limit of quantification (LOQ) of 0.01 mg kg?1 after 56 days of the application of insecticides at both the dosages. The half-life values (t 1/2) of chlorantraniliprole were worked out to be 8.36 and 8.25 days, at recommended and double the recommended dosages, respectively.  相似文献   
113.
Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 μg L?1; Cu was 392 μg L?1 at the extreme downstream, Allahabad and Ni was 146 μg L?1 at midstream, Agra. Largest concentration of Cu was 617 μg kg?1, Ni 1,621 μg kg?1 at midstream while Pb was 1,214 μg kg?1 at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 μg kg?1 in Oreochromis niloticus and 1.55 μg kg?1 in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 μg kg?1 in O. niloticus and 124 μg kg?1 in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02?×?10?4 which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment.  相似文献   
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Imidacloprid is extensively used on a broad range of crops worldwide as seed dressing, soil treatment, and foliar application. Hence, the degradation potential of bacterial strains from sugarcane-growing soils was studied in liquid medium for subsequent use in bioremediation of contaminated soils. The microbe cultures degrading imidacloprid were isolated and enriched on Dorn’s broth containing imidacloprid as sole carbon source maintained at 28 °C and Bacillus alkalinitrilicus showed maximum potential to degrade imidacloprid. Clay loam soil samples were fortified with imidacloprid at 50, 100, and 150 mg kg?1 along with 45?×?107 microbe cells under two opposing sets of conditions, viz., autoclaved and unautoclaved. To study degradation and metabolism of imidacloprid under these two conditions, samples were drawn at regular intervals of 7, 14, 28, 35, 42, 49, and 56 days. Among metabolites, three metabolites were detected, viz., 6-chloronicotinic acid, nitrosimine followed by imidacloprid-NTG under both the conditions. Total imidacloprid residues were not found to follow the first-order kinetics in both types of conditions. This paper reports for the first time the potential use of pure cultures of soil-isolated native bacterium B. alkalinitrilicus and also its use along with natural soil microflora for remediation of imidacloprid-contaminated soils.  相似文献   
116.
In this study, we surveyed diversity in a range of local crops in the Lume and Gimbichu districts of Ethiopia, together with the knowledge of local people regarding crop uses, socio-economic importance, conservation, management and existing threats. Data were collected using semistructured interviews and participant observation. The study identified 28 farmers' varieties of 12 crop species. Among these, wheat (Triticum turgidum) and tef (Eragrostis tef) have high intra-specific diversity, with 9 and 6 varieties respectively. Self-seed supply or seed saving was the main (80?%) source of seeds for replanting. Agronomic performance (yield and pest resistance), market demand, nutritional and use diversity attributes of the crop varieties were highlighted as important criteria for making decisions regarding planting and maintenance. Over 74?% of the informants grow a combination of "improved" and farmers' varieties. Of the farmers' varieties, the most obvious decline and/or loss was reported for wheat varieties. Introduction of improved wheat varieties, pest infestation, shortage of land, low yield performance and climate variability were identified as the principal factors contributing to this loss or decline. Appropriate interventions for future conservation and sustainable use of farmers' varieties were suggested.  相似文献   
117.

Background, aim, and scope  

Zinc is an essential micronutrient element but its concentrations found in contaminated soils frequently exceed those required by the plant and soil organisms, and thus create danger to animal and human health. Phytoremediation is a technique, often employed in remediation of contaminated soils, which aims to remove heavy metals or other contaminants from soils or waters using plants. Arabidopsis (A.) halleri ssp. gemmifera is a plant recently found to be grown vigorously in heavy metal contaminated areas of Japan and it contained remarkably high amount of heavy metals in its shoots. However, the magnitude of Zn accumulation and tolerance in A. halleri ssp. gemmifera need to be investigated for its use as a phytoremediation plant.  相似文献   
118.
Environmental Chemistry Letters - Microbial cells react with intestinal surfaces and produce enzymes and metabolites that influence human health, host metabolism and immunity. Gut...  相似文献   
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Phototransformation of the herbicide metsulfuron methyl was investigated on glass surface under sunlight and ultraviolet (UV) light and compared with dark condition. The half-lives of metsulfuron methyl under UV light and sunlight were found to be 0.5 and 7.8 days respectively. Rate of phototransformation followed first order kinetics with significant correlation coefficient. The major photoproducts were identified as methyl-2-sulfonyl-amino-benzoate, 2-amino-6-methoxy-4-methyltriazine and saccharin (O-sulfobenzoimide). Various metabolites from this study were identified by high performance liquid chromatography (HPLC). Authentic samples required for HPLC comparison were prepared in laboratory and characterized on the basis of nuclear magnetic resonance (NMR) and infra red (IR) spectral data. These metabolites were also identified from metsulfuron methyl treated wheat field soil.  相似文献   
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