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The current study examined whether soil pH could influence the toxicity of herbicides to soybean-rhizobium symbiosis. This can be useful for farmers to minimize the toxicity of them to crop-rhizobium symbiosis via applying their reduced doses. The toxicity of bentazon, metribuzin, and trifluralin to soybean-rhizobium symbiosis was investigated in pH 6.4, 7.2, and 8 soils. Seed inoculation decreased shoot:root (S:R) ratio but increased height, shoot dry weight (SDW), root dry weight (RDW), shoot nitrogen content (SNC), root nitrogen content (RNC), and nitrogen fixation effectiveness (NFE) in the pH 7.2 soil without herbicide application. All herbicides decreased NFE in all soil pH regimes except metribuzin in the pH 6.4 soil. Unlike trifluralin, the toxicity of bentazon and metribuzin to soybean-rhizobium symbiosis was influenced by the soil pH. It can be concluded that soil acidification and alkalization, which can rapidly occur in agroecosystems, can decrease and increase the toxicity of bentazon and metribuzin to soybean-rhizobium symbiosis, respectively.

Laboratory experiments were conducted to evaluate the acute toxicity of a widely used textile dye namely Reactive Red 120 (RR 120) on certain aquatic species such as Pseudokirchneriella subcapitata (green alga), Lemna gibba (duck weed), Daphnia magna (water flea) and Oncorhynchus mykiss (Rainbow trout). All experiments were performed as per the OECD Guidelines for Testing of Chemicals. The toxicity end points of EC50, LC50, NOEC and LOEC for RR 120 were determined with 95% confidence limits using TOX STAT version 3.5. The EC50 of RR 120 for green alga, duck weed and water flea are >100.00, 64.34, 10.40 mg L(-1), respectively and LC50 for Rainbow trout is 78.84 mg L(-1). Based on the results, the test item RR 120 could be classified as non-toxic to green alga, harmful to duck weed and Rainbow trout, toxic to water flea.

Explosives materials are stable in soil and recalcitrant to biodegradation. Different authors report that TNT (2,4,6-trinitrotoluene), RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) and HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) are toxic, but most investigations have been performed in artificial soil with individual substances. The aim of the presented research was to assess the toxicity of forest soil contaminated with these substances both individually as well in combinations of these substances. TNT was the most toxic substance. Although RDX and HMX did not have adverse effects on plants, these compounds did cause earthworm mortality, which has not been reported in earlier research. Synergistic effects of explosives mixture were observed.

TBA is an herbicide in general low acute toxicity and placed into a third category of toxicity. The aim of this study was to determine the effect of TBA and its formulation Radazin TZ-50 in doses of ADI values and 1/100 LD 50 on haematological and biochemical blood parameters in mice. The number of leukocytes was significantly decreased (p < 0.05) in all treated groups compared to non-treated mice (8.81 ± 3.23 × 10(9)/L). The lowest value 3.90 ± 0.74 × 10(9)/L was observed in group treated with TBA (1/100 LD 50) followed by TBA (ADI) 4.49 ± 0.98 × 10(9)/L, Radazin TZ-50 (1/100 LD 50) 4.67 ± 1.24 × 10(9)/L and Radazin TZ-50 (ADI) 4.73 ± 1.15 × 10(9)/L. The values of the enzyme AST was increased from 190.00 ± 26.46-270.00 ± 147.30 U/L in serum of all treated groups as compared to non-treated mice (110.00 ± 20.00). LDH values showed significant increase (3236.67 ± 56.86-4054.33.5 ± 837.16 U/L) as compared to non-treated mice (1010.00 ± 222.71 U/L). Total protein value was significantly (p < 0.05) increased in TBA 1/100 LD50 (63.00 ± 7.48 g/L) and Radazin TZ-50 1/100 LD50 (60.00 ± 2.00 g/L) compared to non-treated mice 52.00 ± 4.00 g/L. Increased serum concentrations of urea and creatinine obtained in mice treated with TBA and Radazin TZ-50 indicates a greater degree of dysfunction of the nephron. TBA and its formulation of Radazin TZ-50 in applied doses demonstrate changes in the number of leukocytes and limited hepatotoxic effects.

The aim of this study was to investigate the toxicity of herbicides (metribuzin and glyphosate), insecticides (imidacloprid and thiamethoxam) and fungicides (hexaconazole, metalaxyl and kitazin) at the recommended and the higher dose rates on plant growth promoting activities of Bradyrhizobium sp. under in vitro conditions. The Bradyrhizobium sp. strain MRM6 was isolated from nodules of greengram plants. Pesticide-concentration dependent progressive-decline was observed in plant growth promoting traits of the strain MRM6 apart from exo-polysaccharides which increased consistently on increasing pesticide concentrations. Generally, the highest toxicity to plant growth promoting characteristics of the Bradyrhizobium sp. strain MRM6 was observed when the strain MRM6 was grown with three times the recommended field rates of glyphosate, imidacloprid and hexaconazole.

Controlled release formulations of metribuzin in polyvinyl chloride, (emulsion); carboxy methyl cellulose, CMC and carboxy methyl cellulose- kaolinite composite, CMC-KAO are reported. The MET-CMC-KAO-3 (T(9)) formulation provided a superior control (76.1%) of weeds in field grown wheat in comparison to metribuzin 75 DF (57.14%) at the dose (350 g a.i. ha(-1)) after 90 days of sowing. The treatment (T(9)) reduced the dry weight of the weed flora after 30 days of sowing (4.0 g m(-2)) and significantly superior over metribuzin 75 DF (6.0 g m(-2)) and control (17.72 g m(-2)). There were nil to negligible metribuzin residue in soil at harvest of wheat crop and were within prescribed limit of 10 mg L(-1) in drinking water (EPA).

The aim of the study was to evaluate acute toxic effects of the preparation Sencor 70 WG (metribuzin 70% W/V) on hematological, biochemical indices and histology of the common carp (Cyprinus carpio L.). In carp exposed for 96 h to Sencor 70 WG in the concentration of 250.2 mg/L, showed significantly lower (p<0.01) values of plasma total proteins, albumins, total globulins, triacylglycerols, lactate dehydrogenase, lactate, inorganic phosphate, hematocrit, hemoglobin concentration, mean erythrocyte volume, the leucocrite value, lymphocyte, and significantly higher (p<0.01) values of glucose, ammonia, calcium, monocytes, neutrophile granulocytes, developmental forms myeloid sequence and basophiles compared to the control group. Histopathological examination revealed hyaline degeneration of the epithelial cells of renal tubules of the caudal kidney. This alteration of kidney resulted in hypoproteinemia, followed by generation of transudate in body cavity.