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31.
大豆种子萌发对镉与模拟酸雨胁迫的响应   总被引:2,自引:0,他引:2  
为了解土壤中镉(Cd)与酸雨对作物种子萌发的环境生物学效应,采用种子常规萌发试验研究了不同浓度的Cd~(2+)溶液与模拟酸雨复合污染对大豆种子萌发过程中发芽率、发芽势、发芽指数、活力指数变化的影响.结果表明,Cd~(2+)对大豆种子萌发的毒害作用比酸雨明显,是构成复合污染的主要因素.Cd~(2+)和酸雨复合污染对大豆种子发芽率和发芽势有显著的正交互作用效应,即存在协同作用.Cd~(2+)与酸雨复合污染对大豆种子发芽指数和活力指数都有影响,但不表现出显著的交互作用效应,表明复合污染对这两项指标是两种污染物单因素效应的简单叠加.综合考虑,Cd~(2+)与酸雨复合污染对大豆种子萌发表现出明显的协同作用.  相似文献   
32.
Transfer of bioactive organic compounds from soil to plants might represent animal and human health risks. Sewage sludge and manure are potential sources for bioactive compounds such as human- and veterinary drugs. In the present study, uptake of the anti-diabetic compound, metformin, the antibiotic agent ciprofloxacin and the anti-coccidial narasin in carrot (Daucuscarota ssp. sativus cvs. Napoli) and barley (Hordeumvulgare) were investigated. The pharmaceuticals were selected in order to cover various chemical properties, in addition to their presence in relevant environmental matrixes. The root concentration factors (RCF) found in the present study were higher than the corresponding leaf concentration factors (LCF) for the three test pharmaceuticals. The uptake of metformin was higher compared with ciprofloxacin and narasin for all plant compartments analyzed. Metformin was studied more explicitly with regard to uptake and translocation in meadow fescue (Festucapratense), three other carrot cultivars (D.carota ssp. sativus cvs. Amager, Rothild and Nutri Red), wheat cereal (Triticumaestivum) and turnip rape seed (Brassicacampestris). Uptake of metformin in meadow fescue was comparable with uptake in the four carrot cultivars (RCF 2-10, LCF approximately 1.5), uptake in wheat cereals were comparable with barley cereals (seed concentration factors, SCF, 0.02-0.04) while the accumulation in turnip rape seeds was as high as 1.5. All three pharmaceuticals produced negative effects on growth and development of carrots when grown in soil concentration of 6-10 mg kg−1 dry weight.  相似文献   
33.
The present study was designed to reveal whether long-term consumption of bitter apricot seeds causes changes in lipid profile and other risk factors for cardiovascular diseases. The study group consisted of 12 healthy adult volunteers (5 females and 7 males). The average age of women was 41.60 ± 11.28 years and the average age of men was 36.71 ± 13.70 years. Volunteers consumed 60 mg kg?1 of body weight of bitter apricot seeds divided into 8–12 doses daily for 12 weeks. Volunteers were recruited from the general population of Slovak Republic. After 12 weeks, mean body weight of the participants increased from 77.34 to 78.22 kg (P > 0.05). The average total cholesterol levels decreased from 4.86 mmol L?1 at the beginning of the study to 4.44 mmol L?1 at the end of the study (P < 0.05). We did not observe any significant increase in high-density cholesterol (from 1.55 to 1.60 mmol L?1). The average low-density cholesterol levels decreased from 2.93 mmol L?1 at the beginning of the study to 2.31 mmol L?1 at the end of the study (P < 0.001). Concentration of triglycerides increased significantly over the 12-week intervention period from 0.84 to 1.17 mmol L?1. After the intervention, the high-sensitivity C-reactive protein level decreased from 1.92 to 1.23 mg L?1, but results were non-significant (P > 0.05). Creatine kinase serum levels increased from 2.31 to 2.77 mg L?1 (P > 0.05) over the 12-week intervention period. The results suggest that regular intake of bitter apricot seeds may be considered potentially useful for prevention of cardiovascular diseases.  相似文献   
34.
Sound whole-seed faba beans were treated with (methyl-14C) fenitrothion [O, O-dimethyl-O-(3-methyl-4-nitrophenyl) phosphorothioate] at 5 and 10 mg insecticide/kg seeds, a dose normally used in practice. During the 30 weeks of storage period, the penetration and distribution of insecticide residues were studied. The amount of surface residues, internal residues and bound insecticide residues was estimated. Surface residues were found to decrease with the increase in time of storage, whereas internal residues showed a gradual increase with time apparently not dose dependent. Grain-bound residues increased with time and reached to its maximum (14–18%) after 24 weeks of storage. Chromatographic analysis of the internal extracts revealed the presence of the parent compound together with three main metabolites which were found in both free and conjugated form. Feeding mice for 90 days with a diet mixed with total internal fenitrothion residues in stored faba beans led to a reduction in body weight gain, and an appreciable decrease in cholinesterase activity of 32% for plasma and 15% for red blood cells (RBCS) after two months of experiment. Also, a significant decrease was showed in both total protein and albumin concentration at the end of feeding period (90 days). Liver and kidney function, as well as lipid profile of treated mice significantly increased at the end of feeding period. After a one-month recovery period, all the examined blood parameters returned to about the control values except blood urea and serum triglyceride.  相似文献   
35.
The purpose of this study was to investigate common pesticides in stored wheat at Kermanshah province's silos in Iran. A simple, inexpensive, reliable and environmentally friendly method based on dispersive liquid–liquid microextraction with solidification of floating organic drop was developed. The analytical characteristics of the method were determined. Also, various parameters such as the materials of the silos, types of ownerships of the silos, geographic orientation of silo locations and climatic conditions of silo locations on pesticide residues in studied wheat samples were investigated. Among all the studied parameters, the climatic conditions of silo locations showed the highest influence on pesticide residues in wheat samples. Generally, 61.2% of the samples had pesticide levels below the method detection limits and 38.8% of the total samples had at least one of the understudied pesticides. Also, 13.9% of the samples had deltamethrin residues, 16.7% of the samples had permethrin, 22.2% of the samples had malathion, 11.1% of the samples had both permethrin and malathion and 2.8% of the samples had both deltamethrin and malathion. The results revealed that the residues of deltamethrin and malathion were lower than the standard level announced by European Union regulation and only three samples contained permethrin higher than Europe standard level.  相似文献   
36.
应用高梯度磁分离技术处理糖蜜酒精废水   总被引:25,自引:0,他引:25  
采用投磁种的方法进行强化,高梯度磁分离技术可以有效地用于处理有机工业废水,废水经处理后其浊度、色度和COD都大大降低.系统地研究了这一新方法应用于处理糖蜜酒精废水以及磁种再生的全过程,探讨了磁种的活性、处理效果及其影响因素.结果表明,废水磁种强化磁分离处理过程主要是一个pH控制过程,最佳处理pH值为5左右,磁种再生pH值为11左右.  相似文献   
37.
离子液体对三种农作物发芽和生长的毒性研究   总被引:5,自引:0,他引:5  
为了考察离子液体的生态毒性,研究了5种离子液体及其浓度变化对3种农作物发芽及生长状况的影响。结果表明:就种子发芽这一生态毒理指标而言,不同作物对离子液体毒性的敏感程度不同,其次序为黄瓜>玉米>白菜;在一定浓度下,离子液体对白菜、黄瓜和玉米均具有一定的毒害作用;对于所考察的5种离子液体,阴离子为卤素的[EMIM]Br和[BMIM]Cl对植物发芽和生长的抑制作用远大于阴离子为烷基硫酸酯和烷基磷酸酯的同类离子液体 [EMIM][ES]、[EMIM][DEP]和[MMIM][DMP]。这种毒性顺序可能与卤素离子对细胞膜较强的穿透能力和由于离子液体的稳定性所造成的阴阳“离子对”的共迁移有关。  相似文献   
38.
Rice seeds (Tianyou, 3618) were used to examine the physiological and biochemical responses to phosphine exposure during germination. A control (0 mg m−3) and four concentrations of phosphine (1.4 mg m−3, 4.2 mg m−3, 7.0 mg m−3 and 13.9 mg m−3) were used to treat the rice seeds. Each treatment was applied for 90 min once per day for five days. The germination rate (GR); germination potential (GP); germination index (GI); antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); and lipid peroxidation measured through via malondialdehyde (MDA) were determined as indicators of the physiological and biochemical responses of the rice seeds to phosphine exposure. These indicators were determined once per day for five days. The results indicated that the GR, GP and GI of the rice seeds markedly decreased after phosphine exposure. The changes in the activities of the antioxidant enzymes due to the phosphine exposure were also significant. The exposure lowered the CAT and SOD activities and increased POD activity in the treated rice seeds compared with controls. The MDA content exhibited a slow increase trend with the increase of phosphine concentration. These results suggest that phosphine has inhibitory effects on seed germination. In addition, phosphine exposure caused oxidative stress in the seeds. The antioxidant enzymes could play a pivotal role against oxidative injury. Overall, the effect of phosphine on rice seeds is different from what has been reported previously for insects and mammals.  相似文献   
39.
王磊  宋乃平*  徐秀梅  徐坤  杨微 《生态环境》2012,(6):1004-1008
选择宁夏中卫市中冶·美利纸业集团的林纸一体化人工速生杨基地作为研究对象,以CBERS/CCD影像和同步实测样地数据为基础,利用相关分析方法筛选出相关系数分别为0.939和0.936的NDVI和RVI两个变量,构建了基于NDVI、RVI及NDVI和RVI的3个人工速生林地叶面积遥感回归估测模型,R2分别为0.882、0.877和0.885,并通过相关检验,估算出研究区不同林龄速生杨林地的叶面积。结合样地的实测净光合速率(PN,Net Photosynthetic Rate,μmol·m-2·s-1),推算出不同林龄的速生杨单位叶面积的年二氧化碳净吸收量,最终估算出整个研究区的年固定碳(CO2)的净增量分别为326 648.66、315 688.73和322 509.04 t。通过与常规方法测得结果的比较,表明遥感结合地面实测数据估算林木固碳是可行的;从建立模型的R2值分析,根据不同植被指数建立的多元模型的精度要优于单一植被指数建立的一元模型;根据估测结果,随着林龄的增长,林木的固碳能力不断提高,但受不同生境的影响,增长速度存在空间差异。  相似文献   
40.
A lactose-binding lectin (TCL) was purified from the seeds of African walnut, Tetracarpidium conophorum, and acute toxicity studies of the lectin were carried out with Swiss albino male mice. Animals were administered doses of TCL from 500 to 2500?mg?kg?1 body weight (b.wt.) orally while intraperitoneally the dose ranged from 10 to 600?mg?kg?1 b.wt. Animals were then assessed for organ and body weight changes, mortality, and histopathology. TCL did not cause any observable toxicity via the oral route; however, when administered intraperitoneally, TCL elicited toxicity with an LD50 of 50?mg?kg?1 b.wt. Death from intoxication was preceded by convulsion, hypoactivity, salivation, ataxia, and weakness. The animals given lethal doses of the lectin showed profound respiratory depression which was judged to be the primary cause of death. Histopathological analysis indicated that the lungs, liver, and spleen were adversely affected while the kidney and other organs were essentially normal. In all the affected organs, the severity of toxicity was dose-dependent as the effect of the lectin became more pronounced with increase of the dose administered.  相似文献   
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