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101.
5种杀虫剂的烟青虫防治效果研究 总被引:1,自引:0,他引:1
5种杀虫剂对烟青虫的毒力试验表明:质量分数为80%~83%的高效氯氰菊酯和86.7%的氰戊菊酯分别稀释2000和1000倍对烟青虫的防治效果较好,LG50分别为0.0322ug.头^-1和0.0582ug.头^-1,久效磷和乙酰甲胺磷稀释1000倍的效果次之,吡虫啉效果最差。 相似文献
102.
几种杀螨剂对3种叶螨的毒力比较 总被引:1,自引:0,他引:1
作者于 1 996年对二斑叶螨 (TetranychusurticaeKoch)、朱砂叶螨 [T .cinnabarinus(Boisdural) ]和山楂叶螨 (T .viennensisZacher)进行了三氯杀螨醇、甲氰菊酯、哒螨酮、霸螨灵等 4种杀螨剂的毒力测定 ,并对 3种叶螨在LC50 和LC95水平上 ,比较了相互之间的毒力差别。结果表明 ,二斑叶螨的毒力最高 ,朱砂叶螨次之 ,山楂叶螨毒力最低。 相似文献
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WU Hai-gang XU Guang-ke HU Jing LIU Jin-ni CHEN Qin-xi ZHANG Ying-bing JI Wan-min YI Ben-chi MA Yun 《中国畜牧兽医》2017,44(8):2523-2528
The purpose of this study was to evaluate the safety of the cefquinome sulfate liposomes by using the acute toxicity test, local irritation test and chronic toxicity test. The results showed that the LD50 of cefquinome sulfate liposomes was 639.73 mg/kg after intramuscular injection of its suspension and 95% confidence interval was 573.06 to 714.17 mg/kg. There was no significant stimulation to muscle. Subchronic toxicity test showed that the weight, haematological indexes and biochemical criterion of rabbits in variety dose had no significant difference compared with normal group (P>0.05). There was no visible pathological changes on the liver,kidney histology. According to pathological observation, the structure of liver and kidney were clear in treated and middle dose groups,but there existed disorganized hepatic cell cord in the liver and hemorrhag between glomerulopathy,tubulointerstitial and hepatic sinusoids in high dose group. All results proved that the cefquinome sulfate liposomes was safe and reliable based on the animal experiments. 相似文献
105.
In order to obtain higher purity and high yield of LPS isolated from Escherichia coli, and evaluate its virulence,excrement of diarrhea piglet was collected as pathological samples, of which, some strains of Escherichia coli were isolated and identified. And furthermore, a strain of Escherichia coli was acquired by 16S rDNA identification. The LPS from this strain of Escherichia coli was isolated with the hot-phenol water method and purified by DNaseⅠ, RNaseA, proteinase K treatment and alcohol precipitation. The polysaccharide, protein and nucleic acid content of purified LPS were detected by phenol-sulfuric acid method, Bradford method and UV points spectrophotometric method. And its bioactivity and acute median lethal dose was determinated by tachypleus amebocyte lysate (TAL) method and acute toxicity experiment method, respectively. The results showed that a strain of highly pathogenic Escherichia coli was successfully isolated. The average yield of purified LPS was 3.74%, the proportion of the polysaccharide was 13.40%, the protein was 0.48%, and the nucleic acid was 0.06%. SDS-PAGE electrophoresis and silver stain showed that the bands were mainly concentrated in the range of 14 to 160 ku. The LAL bioactivity of the prepared LPS was 1.21×107 EU/mg, LD50 of the mouse abdominal cavity was 31.86 mg/kg. The results revealed that the diarrhea piglets in the farm was caused by pathogenic Escherichia coli,purified LPS from this strain of Escherichia coli had the advantages of higher purity, high yield and strong virulence, which would provide theoretical data for clinical prevention and treatment of diarrhea piglets. 相似文献
106.
《Journal of plant nutrition》2013,36(3):619-628
Abstract The phytotoxicity of aluminum (Al) in relation to preculture with phosphates was examined in the rice cultivar Arkansas fortuna. In plants precultured with phosphates, Al did not inhibit shoot growth, while Al retarded shoot growth in plants precultured without phosphates. In contrast, Al inhibited root elongation, irrespective of the presence of phosphates in the preculture solution. A large proportion of the Al in roots was in unknown, insoluble forms. In phosphate‐precultured plants, Al deposition was slightly increased, presumably due to the formation of aluminum phosphates in the roots, and phosphorus levels in shoots were markedly increased. Binding with phosphates may ameliorate the toxicity of Al when it enters the shoots and account for the uninhibited shoot growth in the presence of Al in plants precultured with phosphates. 相似文献
107.
大田常用农药对家蚕的熏蒸毒性测试 总被引:11,自引:4,他引:7
为减少粮桑混栽地区大田使用农药不当对蚕桑生产造成的损失,采用密闭熏蒸法测定了7种大田常用农药对家蚕的熏蒸毒性。在30℃环境中经过24 h,对2龄起蚕的LC50:敌敌畏0.1860 mg/m3,敌畏.毒1.3241 mg/m3,毒死蜱48.4111 mg/m3,氟腈.唑磷139.8818 mg/m3,三唑磷161.1514 mg/m3,氟虫腈208.330 mg/m3,吡虫啉333.330mg/m3时2龄起蚕仍无中毒症状。在25℃下经过24 h,对2龄起蚕的LC50:敌敌畏0.2020 mg/m3,敌畏.毒3.7282mg/m3,毒死蜱91.3669 mg/m3。结果表明:农药对家蚕的熏蒸毒性随着温度的升高而增强;敌敌畏、敌畏.毒对家蚕的熏蒸毒性最强,毒死蜱有一定的熏蒸毒性,三唑磷、氟腈.唑磷、氟虫腈、吡虫啉对家蚕的熏蒸毒性较小。 相似文献
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