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采用硅胶和Sephalex LH-20凝胶色谱柱层析等分离方法对南川卫矛茎提取物的乙酸乙酯组分的化学成分进行了分离纯化,并根据理化性质和核磁共振、质谱等波谱数据进行了结构鉴定.分离得到了11个三萜类化合物,分别鉴定为:木栓酮、3-0-木栓烷-28-羧酸、29-羟基-3-木栓酮、大子五层龙酸、直楔草酸、雷公藤内酯甲、雷公... 相似文献
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以甲醇、乙酸乙酯、氯仿和蒸馏水为溶剂获得4种马缨丹提取液,并以杨梦尼夜蛾和春尺蠖幼虫为受体,对其进行了拒食和触杀活性的测定.结果表明:乙酸乙酯提取液(100 mg/mL)对杨梦尼夜蛾和春尺蠖幼虫拒食活性最强,蒸馏水提取液次之,甲醇和氯仿提取液在4种提取物活性最差;马缨丹4种溶剂提取液对杨梦尼夜蛾和春尺蠖具有一定的触杀作用,但活性均不高. 相似文献
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对广东省梅州市梅江区西阳镇林林试验样地进行调查,初步掌握了辣木人工林为害害虫的
主要种类、发生规律以及空间分布。结果表明:辣木人工林主要害虫种类有含夜蛾 Prodenia litura、小
菜蛾 Plutella xylostella、赤斑白条天牛 Batocera rufomaculata、花蓟马 Frankliniella intonsa、稻管蓟马
Haplothrips aculeatus、斜纹夜蛾 Spodoptera litura 和茶蚜 Toxoptera aurantii 共 7 种;夜蛾与小菜蛾的发生
危害程度已达到重度危害水平,而花蓟马、稻管蓟马与茶蚜则达到中度危害水平,斜纹夜蛾与赤斑白条
天牛的危害程度则为轻度;主要害虫幼虫种群的发生为害高峰时间为 9 月,1 月 -3 月幼虫种群几乎不发
生为害,其余月份幼虫种群虫口密度较低;夜蛾、小菜蛾、花蓟马、稻管蓟马、茶蚜与斜纹夜蛾的幼虫
空间分布均呈均匀分布,而赤斑白条天牛幼虫呈聚集分布,聚集发生的原因是林间外界环境因子与其自
身生物学特性共同相互作用引起的。 相似文献
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竹笋夜蛾发生规律及防治技术 总被引:1,自引:0,他引:1
<正> 竹笋夜蛾属鳞翅目,夜蛾科。在新县、光山、商城、信阳、罗山等县竹产区均有发生,其危害日趋严重。1987年竹笋平均被害率55%,1988年竹笋被害率已达67%。受害笋轻者蛀孔,生长缓慢,节突断头;重者幼笋由绿变黄,腐烂死亡。1985年以来,我们在新县竹区进行了系统观察和室内外防治技术试验。结果表明,选择好防治时间、农药种类、施药方法、药剂浓度,是防治竹笋夜蛾的关键。一、发生及危害规律竹笋夜蛾一年一代,以卵在禾本科杂草上越冬。三月中旬卵孵化,先取食禾本科杂草,被害草呈枯心状。三月下旬为卵孵化盛 相似文献
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两种卵蜂在舞毒蛾卵上的寄生动态 总被引:3,自引:0,他引:3
北京地区大蛾卵跳小蜂和舞毒蛾卵平腹小蜂在舞毒蛾卵上一年可以分别完成4-5代和2—3代。两种卵蜂对舞毒蛾的寄生率因采集时期不同而有差异,以8月采集的卵块寄生率最高。7月中旬至8月中旬采集的卵中大蛾卵跳小蜂的寄生率为2.26—4.18%。7月中下旬采集的,舞毒蛾卵平腹小蜂的寄生率为0.64—0.66%。大蛾卵跳小蜂当年羽化的占99.3%,次年羽化的占0.7%。舞毒蛾卵平腹小蜂当年羽化的占81.0%,次年羽化的为19.0%。为保护两种卵蜂,人工采摘卵块除治舞毒蛾的最好时期是9月下旬至次年3月下旬。 相似文献
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本文报道了为害日本甜柿Diospyros kaki L.F.的害虫种类达54种,隶属于7目25科45属及其危害的不同部位和器官;研究了苹梢鹰夜蛾Hypocala subsafura Guenee和柿梢鹰夜蛾H.moorei Butler、铅灰齿爪锶金龟Holotrichia plumbea Hope、曲胫敉缘蝽Micitis tenebrosa Fabricius和斜纹夜蛾Prodenia lit 相似文献
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印楝提取物对桑天牛产卵、卵孵化及其幼虫存活的影响 总被引:1,自引:0,他引:1
用一定量的印楝提取物处理构树枝条喂饲桑天牛成虫,研究了其对桑天牛产卵、卵孵化及幼虫成活的影响。在室温下,将成对的天牛放在盖有铁丝网的190 mm×240 mm塑料桶中进行实验。每头雌成虫取食印楝提取物0.10 mg0、.15 mg0、.20 mg和0.25 mg后,15 d期间其平均产卵量分别为6.29、3.00、1.67和1.00粒;取食剂量为0.05 mg0、.10 mg、0.15 mg和0.20 mg的孵化率分别为42.38%、41.78%、16.77%和30.00%,当取食量达到0.25 mg时,孵化率为0,卵孵化被完全抑制;取食量为0.15 mg、0.20 mg的幼虫存活率分别为25.00%、33.33%,对照组的平均产卵量、卵孵化率及其子代幼虫存活率分别为16.33、78.91%、72.73%,T检验显示雌成虫取食上述剂量的印楝提取物对抑制其产卵、卵孵化及其子代幼虫存活显著。 相似文献
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冬枣绿盲蝽越冬卵毒力测定与田间防治试验 总被引:4,自引:2,他引:2
通过室内和田间试验,比较了13种不同农药对冬枣越冬卵杀伤力的差异,筛选了3种对冬枣绿盲蝽越冬卵具有较好杀灭作用的农药。室内试验结果表明:在13种农药中,对越冬卵具有较好杀灭效果的有敌敌畏、敌百虫和氰戊菊酯,敌敌畏杀卵效果较好,为75.56%,其次为氰戊菊酯和敌百虫,防治效果分别为71.24%、59.09%。而大田试验,各种农药的杀卵效果较差,氰戊菊酯效果较好,500倍、1000倍处理杀灭率仅为32.42%、22.57%;其次为敌百虫200倍液,杀灭率为21.13%。因此必须采取多种方法才能有效控制绿盲蝽的危害。 相似文献
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The alkaloidal fraction obtained from an ethanolic extract of the leaves of Mikania cordata exhibited significant in vivo antiulcer activity in diclofenac sodium-induced gastric erosions in Long Evans rats. 相似文献
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Schlemper SR Schlemper V da Silva D Cordeiro F Cruz AB Oliveira AE Cechinel-Filho V 《Fitoterapia》2001,72(1):73-75
The antibacterial effects of extracts obtained from Persea cordata stem bark, employed in Brazil to treat infectious diseases, were studied. The ethyl acetate fraction of the hydroalcoholic extract showed activity against pathogenic bacteria which may justify the popular use of the plant. 相似文献
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Macleaya cordata (plume poppy) is used in traditional Chinese medicine for its anti-inflammatory and antibacterial activities. In this study, we examined whether M. cordata extract and/or its major alkaloid constituents, protopine, allocryptopine, sanguinarine and chelerythrine activate the Nrf2 signalling pathway which regulates the expression of cytoprotective enzymes including heme oxygenase-1 (HO-1) and thioredoxin 1. In murine macrophage RAW264.7 cells, M. cordata extract increased both mRNA and protein levels of HO-1. Of the alkaloids examined, only sanguinarine appeared to be responsible for these effects. At the concentration of 2 μM, sanguinarine induced nuclear accumulation of Nrf2, increased the expression of Hmox1 gene encoding HO-1 and elevated HO-1 protein levels. Sanguinarine-induced Hmox1 mRNA expression was suppressed by SB203580, a pharmacologic inhibitor of p38 mitogen-activated protein kinases (p38 MAPKs). The upregulation of HO-1 in RAW264.7 cells by sanguinarine was, however, accompanied by decrease in cell viability. Nonetheless, sanguinarine at micromolar, non-cytotoxic concentrations elevated protein levels of HO-1 and thioredoxin 1 in primary cultures of human hepatocytes. We conclude that sanguinarine may, under appropriate conditions, increase the capacity of the enzymatic antioxidant defence system via activation of the p38 MAPK/Nrf2 pathway. 相似文献
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The hexane extract of Phyllanthus maderaspatensis (200 and 100 mg/kg) showed significant hepatoprotection on carbon tetrachloride and thioacetamide induced liver damage in rats. The protective effect was evident from serum biochemical parameters and histopathological analysis. Rats treated with P. maderaspatensis remarkably prevented the elevation of serum AST, ALT and LDH and liver lipid peroxides in CCl(4) and thioacetamide treated rats. Hepatic glutathione levels significantly increased by the treatment with the extracts. Histopathological changes induced by CCl(4) and thioacetamide were also significantly reduced by the extract treatment. The activity of hexane extracts of P. maderaspatensis was comparable to that of silymarin, the reference hepatoprotective drug. 相似文献
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The crude extract of Mikania cordata (1 and 3 g/kg, p.o.) and deoxymikanolide (1) (10 mg/kg, p.o.) significantly inhibited acetic acid-induced writhing in mice. Three other sesquiterpene dilactones isolated from the same plant, namely mikanolide, dihydromikanolide and scandenolide, did not show significant analgesic activity. 相似文献
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Four new neolignans, wilfordiols A-D (1-4), together with five known compounds (5-9), were isolated from an aqueous extract of the dried leaves of Tripterygium wilfordii. Their structures were determined by spectroscopic methods, including 1D and 2D NMR, HRESIMS, and CD experiments. The anti-inflammation activities of compounds 1-9 were evaluated by the inhibitory effect on NO production, in vitro. 相似文献
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J R Villagómez-Ibarra M Sánchez O Espejo A Zú?iga-Estrada J M Torres-Valencia P Joseph-Nathan 《Fitoterapia》2001,72(6):692-694
The antibacterial activity of the hexane, ethyl acetate and methanol extracts of the flowers, leaves and stems of Gnaphalium oxyphyllum var. oxyphyllum, G. liebmannii var. monticola and G. viscosum was investigated. The hexane extracts showed in all cases the higher inhibitions, G. oxyphyllum flower extract exhibiting the wider spectrum of activity. 相似文献