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Cassia occidentalis L. is an annual or perennial Ayurvedic plant which is used in several traditional medicines to cure various diseases. This weed has been known to possess antibacterial, antifungal, antidiabetic, anti-inflammatory, anticancerous, antimutagenic and hepatoprotective activity. A wide range of chemical compounds including achrosin, aloe-emodin, emodin, anthraquinones, anthrones, apigenin, aurantiobtusin, campesterol, cassiollin, chryso-obtusin, chrysophanic acid, chrysarobin, chrysophanol, chrysoeriol etc. have been isolated from this plant. The presented review summarizes the information concerning the botany, ethnopharmacologyquery, phytochemistry, biological activity and toxicity of the C.occidentalis plant. 相似文献
104.
6种杀虫剂对小菜蛾幼虫的室内毒力活性比较 总被引:1,自引:1,他引:0
采用浸叶法测试了虫螨腈、氯虫苯甲酰胺、埃玛菌素、丁醚脲、阿维菌素、氟虫腈6种药剂对小菜蛾3龄幼虫的室内毒力。结果表明,处理后24h,埃玛菌素的毒力最高,丁醚脲的毒力最小,其LC50值分别为22.21mg/L和996.17mg/L:处理后48h,埃玛菌素和氯虫苯甲酰胺的毒力最高,丁醚脲的毒力最小,其L如值分别为13.08mg/L,13.90mg/L和244.57mg/L:处理后72h,氯虫苯甲酰胺和埃玛菌素毒力最高,丁醚脲的毒力最小,其LC50值分别为4.77mg/L.8.59mg/L和135.94mg/L。 相似文献
105.
为了筛选防治苜蓿(Medicago sativa)锈病有效单剂和复配组合,本试验采用盆栽喷雾法,测定了14种杀菌剂及5种复配剂对苜蓿锈菌的毒力,并比较不同复配的协同增效作用。结果表明:在单剂毒力测定中,苜蓿锈菌对嘧菌酯最敏感,EC50为1.8809mg·L-1;甲基硫菌灵的毒力最弱,EC50为747.0022mg·L-1。按照不同杀菌机理的药剂复配机理,嘧菌酯和戊唑醇复配中,1:9组合产生相加作用,其余比例复配均表现为增效作用,其中5:1增效作用最强,增效系数SR为4.9684;嘧菌酯和烯酰吗啉复配,协同增效作用最强的是以1:3组合,增效系数为5.1114,但二者以9:1复配时产生拮抗作用;嘧菌酯和代森锰锌复配,1:7复配组合增效系数SR为4.5757,协同增效作用比较明显。吡唑醚菌酯与苯醚甲环唑复配增效作用最强的是1:5复配组合,其增效系数SR为5.2276;与百菌清的复配,1:7复配组合增效作用最为明显,其增效系数SR为5.8058,因此,从单剂防效看嘧菌酯和吡唑醚菌酯效果最好,复配剂中,吡唑醚菌酯和百菌清以1:7防效最好。 相似文献
106.
The impact of storm water runoff on a small urban stream 总被引:2,自引:0,他引:2
Vilmantė Karlavičienė Sigita Švedienė Danutė Elena Marčiulionienė Peter Randerson Mindaugas Rimeika William Hogland 《Journal of Soils and Sediments》2009,9(1):6-12
Background, aim, and scope In urban areas, storm water runoff often transports various pollutants, some of which settle and form sediments. In order
to have the comprehensive view of the ecological state of storm water runoff recipients, both water and sediments of the stream
must be assessed. In the Baltic Sea Area, the Water Framework Directive & HELCOM Recommendations aim to prevent or minimise
pollution caused by harmful substances arising from storm water runoff, in order to promote the ecological restoration of
the Baltic Sea—one of the most vulnerable seas. The aim of the study was to investigate the toxicity of bottom sediments of
a small storm water runoff recipient focusing on the potential impact of successive discharges of urban storm water. Some
storm water runoff quality parameters and the toxicity of bottom sediments of recipients was studied in this research.
Materials and methods During 9 years, at four discharge points, minimum four grab samples per year at each discharge point were taken for chemical
characterisation. General parameters (pH, SS, BOD7, CODCr and TPH) in liquid phase samples were analysed according to standard methods. Annual limit values were taken from the Lithuanian
EPA requirements for the management of storm water runoff with a focus on prevention and control of contamination. Eleven
composite samples of stream bottom sediments, each consisting of ten sub-samples, were collected in 2006. Toxicity screening
from sediments was performed using the plant Lepidium sativum according to modified I. Magone’s methodology (Magone I, Bioindication of phytotoxicity of transport emission. In: Kachalova
O-L, Zinatne (eds) Bioindication of toxicity of transport emissions in the impact of highway emissions on natural environment. Riga, pp 108–116, 1989). The level of toxic impact of Lepidium sativum (compared to control) was assessed according to the modified method of Wang (Rev Environ Contam Toxicol 126:88–127, 1992).
Results The mean pH of urban storm water runoff does not vary much from neutral, but range values are quite different, from 4.0 up
to 8.7. The highest concentration of SS reached 800 mg L−1, TPH—2.4 mg L−1, BOD7—300 mg O2 L−1 and CODCr—1,400 mg L−1. The SS was above the limit in 64% of total amount of grab samples, TPH—37%, BOD7—41% and CODCr—55%. The toxicity analysis of the bottom sediments showed varying toxicity of bottom sediments along the stream. From nine
analysed samples of bottom sediments, 30% had weak toxicity, 30% medium and 30% strong toxicity on the test organism plant
L. sativum. There was one single sample with no toxic effects, so that the results showed that urban storm water has an unacceptable
environmental impact on recipients. It was also indicated that storm water runoff discharge alone is not the potential source
of toxicity of bottom sediments. The litter demonstrated a weak toxicity of bottom sediments as well.
Discussion Most local authorities do not consider storm water runoff discharges to be a matter of great concern because they believe
that surface runoff arising from rainfall is still relatively clean. The study showed that the current method of monitoring
storm water runoff quality by chemical analyses is not the best tool for environmental impact assessment and must be combined
with toxicity tests of bottom sediments of recipients.
Recommendations and perspectives To avoid the environmental impact of storm water runoff more attention should be paid to the development and implementation
of storm water runoff pollution prevention measures. The study implies that future research concerning the relationships between
storm water runoff deposit characteristics and biological activities must be developed to evaluate the contamination potential
of stream sediment deposits for local aquatic ecosystems. Further studies should be developed to characterise the activities
of the microbial community of storm water runoff sediments, and to monitor bioremediation in situ. 相似文献
107.
Khemais Abdellaoui Monia Ben Halima-Kamel Fatma Acheuk Noureddine Soltani Nadia Aribi Mohamed HabibBen Hamouda 《Pesticide biochemistry and physiology》2013
Experiments were conducted to assess the effect of gibberellic acid (GA3), a plant growth regulator, on Locusta migratoria migratoria fifth instar larvae. Newly emerged larvae were exposed to various concentrations of GA3 administered by topical application or by forced ingestion. Results showed that treated insects exhibited toxic symptoms with a dose-dependent mortality. GA3 toxicity was also demonstrated by perturbation of the moult processes. In fact, we noted that treated insects present exuviations difficulties due to the impossibility to reject the old integuments causing mortality in the 5th instar larvae. Histological study of proventriculus revealed alterations in the epithelial cells and absence of apolysis phenomenon. Data also showed that GA3 induced significant quantitative variation of haemolymph metabolites. These changes result in a significant decrease in the total concentration of proteins and carbohydrates and an increase in the total concentration of haemolymph lipids. 相似文献
108.
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110.
采用菌丝生长速率法,在室内分别测定了啶酰菌胺(Boscalid)、井冈霉素(Jinggangmycin)和己唑醇(Hexacon-azole)对水稻纹枯病菌(Rhizoctonia solani Kühn)的毒力,并进行了田间防治试验。结果表明:啶酰菌胺、井冈霉素和己唑醇对水稻纹枯病菌菌丝生长抑制的EC50值分别为1.0692、96.2859和0.0240μg/mL;50%啶酰菌胺WDG 600倍液在第2次药后14 d对田间水稻纹枯病的防效为63.53%,极显著低于对照药剂20%井冈霉素A WP 1500倍液和5%己唑醇SC 600倍液的防效。 相似文献