18种中草药提取物对褐飞虱和甜菜夜蛾的杀虫活性分析

为了筛选对农产品和环境安全、对害虫高效的植物源杀虫剂,分别采用喷雾法和饲毒法,测定了18种中草药的3种溶剂（水、乙醇、石油醚）提取物对褐飞虱Nilaparvata lugens Stål的触杀活性和对甜菜夜蛾Spodoptera exigua Hübner的胃毒作用。结果表明,各种提取物（0.8 g/mL）对甜菜夜蛾的胃毒作用不明显,校正死亡率最高为33.33%;但对褐飞虱的杀虫活性较高,其中百部、黄柏、榧子、生山栀、鹤虱、木香的乙醇或石油醚提取物,对褐飞虱3龄若虫的24 h校正死亡率均在80%以上,其石油乙醚提取物的LC50值依次为：0.0826,0.0455,0.0145,0.0047,0.0038,0.0033 g/mL。采用系统溶剂法分析发现,木香和鹤虱的主要杀虫活性成分均在氯仿萃取物中,表明其杀虫成分易溶于较弱极性溶剂中。进一步通过活性追踪法,对鹤虱提取物的柱层析各流分的活性检测表明,其杀虫活性成分的Rf值为0.5556~0.5926。该研究为进一步纯化新型植物源杀虫物质并确定其分子结构,从而开发其应用前景及发现新的杀虫活性先导化合物奠定了基础。     

藜芦杀虫活性的初步研究

先后以乙醇、氯仿和正丁醇为溶剂,提取了熊耳山区植物藜芦根茎中的活性物质。得到3个提取物:乙醇提取物、氯仿萃取物和正丁醇萃取物,产率分别为2.93%、1.14%和0.58%。测定了3种溶剂萃取物对粘虫、蚜虫、朱砂叶螨和蚊幼虫的毒杀活性。结果说明:这几种提取物都具有良好的毒杀效果。氯仿提取物对3龄粘虫有很强的拒食作用;乙醇提取物对4龄蚊幼虫的杀虫活性最高;3种溶剂萃取物对蚜虫的毒杀能力大小次序为:氯仿提取物>正丁醇提取物>乙醇提取物;对朱砂叶螨的毒杀力大小为:乙醇提取物>氯仿提取物>正丁醇提取物。采用试管反应法和层析法对藜芦根茎提取物进行化学成分预试,结果显示:乙醇提取物、氯仿提取物和正丁醇提取物中均含有生物碱类活性物质。     

杠柳萃取物对小菜蛾幼虫的毒杀活性研究

以杠柳Periploca sepium Bunge的根为材料进行甲醇超声波提取,粗提物以水／氯仿（1：1,v／v）萃取获得杠柳根氯仿萃取物。测定了萃取物对小菜蛾Plutella xyllostellaL．3龄幼虫的胃毒和触杀活性。实验结果显示,在50μg／头剂量处理下24h和48h后,氯仿萃取物对小菜蛾3龄幼虫的胃毒死亡率分别为82．22％和92．59％,显著高于触杀死亡率58．89％和68．15％。这一结果表明,杠柳根中含有对小菜蛾幼虫具有较强胃毒作用的活性成分。     

核桃楸叶乙醇提取物对三种常见害虫的杀虫活性

在室内测定了核桃楸叶乙醇提取物对三种常见害虫即温室白粉虱Trialeurodes vaporariorum、小菜蛾Plutella xylostella及豌豆蚜Aphis craccivora的毒力作用。结果表明,核桃楸叶乙醇提取物对白粉虱、小菜蛾和蚜虫均表现出较好的毒杀作用,其LC50分别为0.7527、0.7924和0.2121 g/L;在稀释质量浓度为2.0395 g/L时,白粉虱成虫和小菜蛾幼虫的校正死亡率分别为9448%和9800%,而在稀释浓度为0.9518 g/L时,蚜虫的校正死亡率为89.35%。核桃楸叶乙醇提取物对温室白粉虱、小菜蛾幼虫及蚜虫表现出较好的杀虫活性。     

灰毛豆甲醇提取物的杀虫活性

研究灰毛豆(Tephrosia purpurea)各部位提取物的杀虫活性及其作用方式。结果表明,灰毛豆对白纹伊蚊Aedes albopictus Skuse幼虫、菜青虫Pieris rapae(L.)、斜纹夜蛾Prodenialitura(Fabricius)幼虫和黄曲条跳甲Phyllotreta striolata(Fabricius)成虫都有杀虫活性。灰毛豆种子、树皮、根皮、豆荚、枝条和树叶的甲醇提取物对白纹伊蚊4龄幼虫24h的LC50值分别是22.1,97.7,36.6,142.6,165.6和618.3mg.L-1,树干木质部没有杀虫活性;灰毛豆种子、树皮和根皮甲醇提取物对3龄菜青虫24h的触杀毒力LC50值分别是232.1,206.3和236.7mg.L-1;种子、树皮、根皮、枝条、树叶和豆荚对3龄菜青虫的24h胃毒毒力LC50值分别是192.6,168.4,249.7,524.5,1001.0,和510.7mg.L-1。在取食或接触有提取物的叶碟后,5龄菜青虫会出现取食量减少和生长发育变慢的亚致死现象。这些研究结果表明,灰毛豆除茎干木质部以外的其它各部位均含有杀虫活性成分,其作用方式为胃毒和触杀。     

葎草不同溶剂提取物和萃取物的杀虫活性

对律草[Humulus scandens(Lour.) Merr.]全草干粉的不同溶剂提取物以及丙酮提取物的不同溶剂萃取物的杀虫活性进行了研究.在葎草的石油醚、苯、三氯甲烷、乙酸乙酯、丙酮和乙醇提取物(333 g·L-1)中,丙酮和乙醇提取物对小菜蛾(Plutella xylostella L.)的触杀作用较强,其中丙酮提取物的触杀作用最强,试虫的48h校正死亡率达到86.67％.6种溶剂提取物(100g·L-1)对小菜蛾的拒食活性均较弱,24和48 h拒食率仅为9.65％～ 20.45％.6种溶剂提取物对棉蚜(Aphis gossypii Glover)均有较强的触杀效果.其中丙酮提取物的触杀作用最强,经50g·L-1丙酮提取物处理后棉蚜24和48 h的校正死亡率分别为76.78％和85.64％,而经100g·L-1丙酮提取物处理后棉蚜24和48 h的校正死亡率分别为82.63％和92.53％.丙酮提取物的石油醚、三氯甲烷和乙酸乙酯萃取物对小菜蛾均有一定的触杀活性,且随萃取物浓度提高及处理时间的延长触杀活性增强;其中石油醚萃取物的触杀作用最强,经25.0g·L-1石油醚萃取物处理后小菜蛾24和48 h校正死亡率分别达到80.00％和96.67％ 研究结果表明:葎草丙酮提取物对小菜蛾和棉蚜的杀虫活性均最强,其主要有效杀虫活性成分存在于丙酮提取物的石油醚萃取物中.     

亮叶中南鱼藤的杀虫活性及有效成分

研究了亮叶中南鱼藤Derris fordii var. lucida的杀虫活性及有效成分。通过生物测定确定了该植物提取物对几种害虫的杀虫活性及其作用方式,并在活性跟踪的基础上,通过萃取、柱层析、薄层制备、重结晶、核磁共振和质谱等方法对其有效成分进行了分离和鉴定。结果表明,亮叶中南鱼藤不同部位甲醇提取物中仅根部提取物表现出杀虫活性。根甲醇提取物对白纹伊蚊Aedes albopictus 4龄幼虫、棉蚜Aphis gossypii Glover 无翅成蚜、豆蚜Aphis craccivora Koch无翅成蚜、桃蚜Myzus persicae (Sulzer)无翅成蚜、甘薯天蛾Herse convolvuli L. 2龄幼虫、三化螟Scirpophaga incertulas (Walker)初孵幼虫、菜青虫Pieris rapae (L.) 2龄幼虫和黄曲条跳甲Phyllotreta striolata (Fabricius)成虫都有毒杀效果,其LC₅₀值分别是260.3 mg/L、234.6 mg/L、141.3 mg/L、16.4 mg/L、233.4 mg/L、20.8 mg/L、11.7 mg/L和148.4 mg/L。根甲醇提取物对甘薯天蛾3龄幼虫24 h的触杀和胃毒毒力LC₅₀值分别为101.6 mg/L和234.9 mg/L。此外,亚致死剂量的根甲醇提取物对甘薯天蛾3龄幼虫还有拒食和抑制生长发育的作用。从根中分离和鉴定了3个化合物,即鱼藤酮、6a,12a-脱氢鱼藤素和β-谷甾醇。鱼藤酮和6a,12a-脱氢鱼藤素对三化螟初孵幼虫表现出毒杀活性,24 h的LC₅₀值分别是2.6 mg/L和5.3 mg/L。结论为：亮叶中南鱼藤仅根为活性部位,该甲醇提取物对棉蚜等多种害虫有活性,其主要作用方式为触杀和胃毒,鱼藤酮和6a,12a-脱氢鱼藤素是根中的主要杀虫活性成分。     

喜旱莲子草提取物的杀虫活性

【背景】喜旱莲子草是全球性恶性入侵杂草,近年来在我国已呈蔓延之势,对经济及生态环境造成严重破坏。目前已开展了其入侵机制和生物防治等方面的研究,然而,针对其资源化利用的研究较少。【方法】分别研究了喜旱莲子草的石油醚、氯仿、乙酸乙酯和正丁醇等溶剂提取物对小菜蛾、斜纹夜蛾的选择忌避、触杀和胃毒作用。【结果】喜旱莲子草各有机相提取物对小菜蛾和斜纹夜蛾均具有一定的选择忌避作用。随着处理时间的延长,不同溶剂提取物对小菜蛾和斜纹夜蛾的触杀和胃毒作用效果逐渐增强,且校正死亡率与提取物浓度呈正相关关系;经喜旱莲子草石油醚提取物、乙酸乙酯提取物和正丁醇提取物4000 g·L-1处理后,小菜蛾的触杀校正死亡率均达到70%,经石油醚提取物、乙酸乙酯提取物、正丁醇提取物和水提取物4000 g·L-1及正丁醇层和水层500 g·L-1处理后,斜纹夜蛾的触杀和胃毒校正死亡率均达到80%。【结论与意义】该研究结果对喜旱莲子草的进一步研究开发具有参考价值。     

担子菌黄硬皮马勃杀虫活性研究

研究了担子菌黄硬皮马勃 SclerodermacitrinumPer. 子实体提取物对3龄粘虫的杀虫活性.黄硬皮马勃甲醇-氯仿总浸膏及其石油醚萃取物在浓度为25mg·mL-1时,对3龄粘虫的48h拒食率分别为96.8%和81.3%,而其氯仿及正丁醇萃取物的拒食活性相对较弱;石油醚浸膏具有较强的毒杀作用,在浓度10mg·mL-1时,3龄粘虫的48h校正死亡率均大于80%;石油醚萃取物的触杀活性相对较弱,25mg·mL-1剂量对3龄粘虫7d内的校正死亡率小于60.0%.     

瑞香狼毒根提取物对山楂叶螨的生物活性

采用不同的生物活性测定方法比较了瑞香狼毒(Stellera chamaejasme L.)根部4种不同溶剂提取物的杀螨活性。结果表明,瑞香狼毒根提取物对山楂叶螨(Tetranychus viennensis Zacher)有很好的触杀和内吸活性。在触杀活性测试中,石油醚提取物和氯仿提取物的杀螨活性最高;在内吸作用中,乙醇、氯仿和石油醚提取物的杀螨活性均较高,杀螨效果显著。在对石油醚提取物的不同溶剂萃取物进行生物活性追踪测定中发现,石油醚萃取物和氯仿萃取物具有较高的生物活性,浓度为0.6 g.L-1,山楂叶螨的24 h校正死亡率分别达到93.22%和79.66%。     

trans-2,5-Hexadien-l-yl Chrysanthemates and Related Esters

As a simplified model of natural pyrethrins, trans-2,5-hexadien-l-yl chrysanthemate (V), and its 2- or 3-methyl substituted homologues (III and IV), were prepared and tested for insecticidal activities against houseflies. All these compounds retained sufficient insect toxicity to illustrate an interesting relationships between chemical structure and insecticidal activity.

The cis isomer (XII) of compound V and two positional isomers, 2-methylene-4-penten-l-yl and 1,5-hexadien-3-yl chrysanthemates (XIII and XIV), were also synthesized. Of these isomers, XIII was very slightly active, but the other isomers (XII and XIV) were completely ineffective.

On the other hand, the insecticidal activity of 5-hexen-2-yn-l-yl ester (XV), en-yne analogue of V, was almost the same as that of V.     

4种杀虫剂对南亚实蝇各虫态不同日龄的毒力测定

为明确南亚实蝇Bactrocera tau Walker不同发育阶段、不同日龄以及不同性别成虫对常用杀虫剂的敏感度,本研究采用胃毒法测定了杀虫剂对南亚实蝇室内种群幼虫和成虫的活性,采用浸泡法测了杀虫剂对卵和蛹的活性.结果表明4种杀虫剂对南亚实蝇不同日龄各虫态的毒杀活性存在差异,随日龄增加,各虫态对不同药剂的耐药性增加,且耐药性的强弱不同.高效氟氯氰菊酯EC对南亚实蝇卵、2日龄和5日龄幼虫具有较好的毒杀活性,LC50分别为2.88 mg/L、2.08 mg/L和6.39 mg/L,辛硫磷EC、多杀霉素SC以及高效氯氰菊酯EC的杀虫活性较差,LC50分别为4.71 mg/L、3.95 mg/L和11.60 mg/L;幼虫对高效氟氯氰菊酯EC的耐药性增长较快,对多杀霉素SC的耐药性增加较慢;多杀霉素SC对2日龄和5日龄的蛹和雌雄成虫的毒杀活性较高,但耐药性增加较快,蛹对辛硫磷EC的耐药性增长较慢,雌雄成虫均对高效氯氰菊酯EC耐药性增长较慢,不同日龄的雌成虫的耐药性均高于雄成虫.由于南亚实蝇世代重叠严重,在成虫暴发期之前,可将高效氟氯氰菊酯EC作为首选药剂使用,在成虫暴发期之后防治时可将多杀霉素SC作为优选药剂使用,防治最佳时期为各虫态的初期.     

Iridoid glucosides with insecticidal activity from Galium melanantherum

The insecticidal activity of the endemic species Galium melanantherum was evaluated against Crematogaster scutellaris ants and Kalotermes flavicollis termites. Iridoid glucosides 1-7 were isolated for the first time as metabolites of the investigated plant, along with the coumarin scopolin. The main components of the extract were found to be the non-acetylated iridoids: geniposidic acid (1), 10-hydroxyloganin (2), deacetyldaphylloside (3), monotropein (4), deacetylasperulosidic acid (5) and scandoside (6), while asperulosidic acid (7) was present only in minute quantities. All isolated metabolites were identified on the basis of their spectral data. Laboratory bioassays revealed significant levels of toxicity for 1-4 against Kalotermes flavicollis termites and Crematogaster scutellaris ants.     

Chemical Constituents and Activities of the Essential Oil from Myristica fragrans against Cigarette Beetle Lasioderma serricorne

Essential oil extracted from nutmeg seeds (Myristica fragrans Houtt .) by hydrodistillation was subjected to GC/MS and GC analysis. A total of 27 constituents were identified, of which eugenol (19.9%), methylisoeugenol (16.8%), methyleugenol (16.7%), sabinene (11.8%), and terpinen‐4‐ol (8.5%) were the major components. The essential oil was tested against Lasioderma serricorne for insecticidal and repellent activity, the LD₅₀ value at the end of 24 h exposure period was 19.3 μg/adult. Six active compounds were isolated by bioassay‐guided fractionation. They were identified as eugenol ( 1 ), methyleugenol ( 2 ), methylisoeugenol ( 3 ), elemicin ( 4 ), myristicin ( 5 ), and safrole ( 6 ). Among these isolates, 4 showed the strongest contact toxicity against L. serricorne adults with an LD₅₀ value of 9.8 μg/adult. Repellency of crude oil and active compounds were also determined. Compounds 1, 2, 4 , and 5 were strongly repellent against the cigarette beetle and exhibited the same level of repellency compared with the positive control, DEET. The results indicate that the essential oil of M. fragrans and its active constituents have potential for development as natural insecticides and repellents to control L. serricorne.     

Repellent action and contact toxicity mechanisms of the essential oil extracted from Chinese chive against Plutella xylostella larvae

Botanical pesticides play increasingly important roles in the control of agricultural pests. In this study, the insecticidal effects, specifically the repellent action and contact toxicity, of the essential oil extracted from Chinese chive (EOC) against Plutella xylostella larvae were confirmed. The mechanisms of repellent’s action were studied using electroantennograms (EAGs), and the effects on glutathione S‐transferase (GST), carboxylesterase (CarE), and acetyl cholinesterase were investigated after EOC treatments. The EOC affected the EAG results and inhibited the activities of GST and CarE in treated P. xylostella larvae, which could explain its insecticidal effects. And, four pyrazines showed greater repellent activities than that of the EOC, which was confirmed as the main active compounds of EOC.     

Screening of insecticidal activity of plant essential oils and extract-based formulations against four agricultural insect pests and their risk assessment

Frankliniella occidentalis (Pergande), Myzus persicae (Sulzer), Plutella xylostella (L), and Spodoptera exigua (Hübner) are notorious agricultural insect pests worldwide. Due to the rapid development of resistance to the conventional insecticides, the number of available insecticides might be reduced in a near future, and botanical insecticides can be considered as one of the potential candidates to solve this problem. In the present study, test formulations were prepared using plant essential oils and extracts as main active ingredients, and their insecticidal activity and phytotoxicity were examined. Among the combinations tested, two oil-in-water formulations of NRS-13 containing thyme white oil and NRS-24 containing basil and rosemary oils were selected based on their notable insecticidal activity and low phytotoxicity. Chemical analyses on the active essential oils, the quantitative analysis of the major components in the formulations, insecticidal activities under pot and field conditions, their acute toxicity on mammals, and ecotoxicity on fish were also examined. The NRS-13 (BaechooSafer^TM) and NRS-24 (JindiOut^TM) formulations showed species-specific insecticidal activity against P. xylostella and M. persicae, respectively. In addition, both formulations produced low acute oral and dermal toxicity, skin and eye irritation, and fish toxicities, which suggests those formulations based on essential oils could be considered as insecticides for pest control in small-scale environments in organic farming.     

苏云金芽孢杆菌鲇泽变种7—29杀虫蛋白质结构基因的...

The regulative region (181bp) and the fifth toxic active domain (217bp) were removed from the insecticidal protein gene of Bacillus thuringiensis var. aizawai 7-29. After the synthesis of the adaptor (15bp) that contains initiation codon (ATG) and the PCR synthesis of the fifth toxic active domain (229bp) that contains stop codon (TAA), were inserted into on 5' truncated and 3' truncated of the coding fod N-terminal peptid's DNA fragment, that to become a modified structural gene. The modified structural gene can be play initiatic translation-function and stop translation-function during translation of insecticidal protein. The insecticidal protein was determined by western blotting, showed the expression of modified structural gene in Escherichia coli JM 103. The bioassay of insecticidal proteins showed the 3' truncated and 5' truncated of insecticidal gene was higher toxic active than the 3' truncated of insecticidal gene in Escherichia coli JM 103.     

Fumigant activity of plant essential oils and components from Schizonepeta tenuifolia against Lycoriella ingenua (Diptera: Sciaridae)

Plant essential oils from 21 plant species were tested for their insecticidal activities against larvae of Lycoriella ingenua Dufour (Diptera: Sciaridae) by using a fumigation bioassay. Good insecticidal activity against larvae of L. ingenua was achieved with essential oils of Acorus gramineus Solander, Schizonepeta tenuifolia Briquet, and Zanthoxylum piperitum De Candolle at 25 microg/ml air. S. tenuifolia oil showed the most potent insecticidal activity among the plant essential oils. At 12.5 microg/ml air concentration, S. tenuifolia oil caused 96.6% mortality, but mortality decreased to 60% at 3.125 microg/ml air. Analysis by gas chromatography-mass spectrometry led to identification of three major compounds from S. tenuifolia oil. These three compounds were tested individually for their insecticidal activities against larvae of L. ingenua and compared with the toxicity of dichlorvos. Pulegone was the most toxic, followed by menthone and limonene with LC50 values of 1.21, 6.03, and 15.42 microg/ml, respectively. LC50 of dichlorvos was 8.13 microg/ml. Effects of S. tenuifolia and its components on growth of Pleurotus ostreatus (Jacq. ex Fr.) Kummer also were investigated.     

Evaluation of common cocklebur Xanthium strumarium leaf extract as post‐harvest grain protectant of black gram against pulse beetle Callosobruchus chinensis (Coleoptera: Bruchidae) and isolation of crude compound

The pulse beetle Callosobruchus chinensis L. is considered the most important stored grain pest of black gram Vigna mungo Hepper in Bangladesh and other tropical and subtropical countries. Bioactive compounds derived from plants can be used to control of the pulse beetle as a potential alternative to synthetic insecticides. Therefore, aqueous extracts of common cocklebur Xanthium strumarium L. leaf was examined for insecticidal properties against C. chinensis. The extracts showed toxicity, repellent properties, inhibited fecundity and adult emergence of the insects, and protected grains. Insect mortality was accounted highest (72.6%) with 4% extract at 4 days after treatment. The beetles showed highest repellency rate (58.0%) with 4% concentration at 1 hour exposure; however insect repellency decreased with time. The beetles exerted the lowest fecundity and grain damage and produced the lowest number of offspring when they were reared on grains treated with 4% extract. The insecticidal compounds present in common cocklebur leaf were extracted in chloroform and ethanol, and isolated by thin layer chromatography (TLC) and spectral studies (¹H‐NMR and IR), which identified the presence of aromatic ester, n‐hexyl salicylate or o‐hydroxy‐n‐hexyl‐benzoate and a long‐chain ketone. Therefore, naturally occurring X. strumarium and its derivatives may be potential components for integrated management of C. chinensis.     

In vivo anti-inflammatory and antinociceptive activity evaluation of phenolic compounds from Sideritis stricta

An acetone extract obtained from aerial parts of S. stricta Boiss. & Heldr. apud Bentham, its fractions and phenolic compounds were investigated for their in vivo anti-inflammatory and antinociceptive activities. For the anti-inflammatory activity and for the antinociceptive activity assessment, carrageenan-induced hind paw edema and p-benzoquinone-induced abdominal constriction tests were used, respectively. The acetone extract of the plant and its phenolic fraction exhibited potent inhibitory activity against both bioassay models in mice. From the active phenolic fraction a well-known phenylethanoid glycoside, verbascoside (acteoside) (1), and two flavonoid glycosides, isoscutellarein 7-O-[6"'-O-acetyl-beta-D-allopyranosyl-(1-->2)]-beta-D-glucopyranoside (2) and isoscutellarein 7-O-[6"'-O-acetyl-beta-D-allopyranosyl-(1-->2)]-6"-O-acetyl-beta-D-glucopyranoside (3), were isolated. During phytochemical studies we also isolated a methoxyflavone, xanthomicrol (4), from the non-polar fraction. The structures of the isolated compounds were established by spectroscopic evidence (UV, IR, 1D- and 2D-NMR, MS). Although antinociceptive and anti-inflammatory activities of the phenolic components were found not significant in the statistical analysis, compounds 1 to 3 showed a notable activity without inducing any apparent acute toxicity as well as gastric damage. Furthermore, a mixture of flavonoid glycosides (2 + 3) exhibited a significant inhibitory effect in both models at a higher dose.