首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 468 毫秒
1.
Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir. ) Sch.Bip. ) is a plant species endemic to the east Adriatic coast. The bioactive substance of Dalmatian pyrethrum is a natural insecticide, pyrethrin, a mixture of six active components (pyrethrins I and II, cinerins I and II, and jasmolins I and II). The insecticidal potential of pyrethrin was recognized decades ago, and dried and ground flowers have traditionally been used in Croatian agriculture and households. A total of 25 Dalmatian pyrethrum populations from Croatia were studied to determine the pyrethrin content and composition, and to identify distinct chemotypes. The total pyrethrin content ranged from 0.36 to 1.30% (dry flower weight; DW) and the pyrethrin I/pyrethrin II ratio ranged from 0.64 to 3.33%. The statistical analyses revealed that the correlations between the percentage of pyrethrin I and of all the other components were significant and negative. The total pyrethrin content was positively correlated with the percentage of pyrethrin I and negatively correlated with cinerin II. The multivariate analysis of the chemical variability enabled the identification of five chemotypes among 25 Dalmatian pyrethrum populations. The chemical characterization of indigenous Dalmatian pyrethrum populations may serve as a good background for future breeding and agricultural exploitation.  相似文献   

2.
 Rapid mass propagation of Chrysanthemum cinerariaefolium from young flower heads was developed to compare the ability of callus, in vitro shoots and rooted plants, and original plants to synthesize pyrethrins. The ability to synthesise all six pyrethrin components increased with differentiation. Jasmolin II and cinerin II were the main products present in mother plant shoots, whereas pyrethrin I was the greater component present in callus and in vitro plants. Clonal propagation increased the pyrethrin I content compared to that of plant shoots and young flowers. Total pyrethrin content was the same in in vitro and plant shoots, but lower in these shoots than in young flowers. The pyrethrin I/pyrethrin II ratio, which is directly related to insecticidal activity, varied from 3.4 in in vitro shoots to 0.87 in mother plant shoots and young flowers. Received: 11 July 1998 / Revision received: 10 March 1999 / Accepted: 12 April 1999  相似文献   

3.
The preparation of a pyrethrum extract in highly refined heavy mineral oil, suitable for use as a basis of reference in the biological evaluation of commercial pyrethrum-heavy oil preparations, is described. The solution was standardized with respect to colour, resin content and equal proportions of the pyrethrins. A standard solution containing pyrocatechol remained stable, when judged by the chemical determination of the pyrethrins, over a period of months.
When applied in a heavy mineral oil medium, pyrethrin II was shown to possess a toxicity to Tribolium castaneum Hbst. approaching, if not equal to, that of pyrethrin 1. When applied in an aqueous medium the toxicity of pyrethrin II was very much lower than that of pyrethrin I.  相似文献   

4.
There is need for a technique whereby a given insecticidal preparation can be compared with a standard containing 0.8% (w/v) pyrethrin 1 in a heavy white oil and pronounced biologically equal or inferior to the standard within known and reasonable limits. A film method was investigated, Tribolium castaneum beetles being used as the test insects.
Numerous factors which may influence the kill achieved are discussed. The results of preliminary work, planned to help in the standardization of some of these factors, are summarized.
Several materials were tested to ascertain their suitability for reception of the insecticidal film and, as thin greaseproof paper showed promise, its possibilities were explored. Although 0.3 % pyrethrin I could be distinguished from 0.4%, 0.5% could not be distinguished from 0.8%, and the results throughout were very heterogeneous.
Woven Nylon proved more satisfactory, since the test just failed to establish a significant difference between 0.6 and 0.8% pyrethrin 1. The origin of a pink coloration of the substrate, when T. castaneum beetles were confined on Nylon sprayed with pyrethrum in oil, was investigated.
Whatman filter paper no. 544 proved the best substrate, and a comparative test on it will distinguish 0.65% pyrethrin 1 from the standard 0.8%; the limit could probably be raised to 0.7%.
The influence of several factors on the homogeneity of the results was investigated, and the importance was shown of allowing beetles time to recover from the mechanical shock inherent in the method of counting into batches.
Directions are given for carrying out the film technique for comparing preparations of relatively high pyrethrin content. The method does not measure the direct spray or fumigant action of the insecticide.
The technique described is compared with the Peet-Grady method for evaluating liquid household insecticides of low pyrethrin content. A simplified, but less accurate, design for the test is indicated.  相似文献   

5.
Biosynthesis of pyrethrin I in seedlings of Chrysanthemum cinerariaefolium   总被引:2,自引:0,他引:2  
The biosynthetic pathway to natural pyrethrins in Chrysanthemum cinerariaefolium seedlings was studied using [1-13C]d-glucose as a precursor, with pyrethrin I isolated using HPLC from a leaf extract. The 13C NMR spectrum of pyrethrin I from the precursor-administered seedlings indicated that the acid moiety was biosynthesized from d-glucose via 2-C-methyl-d-erythritol 4-phosphate, whereas the alcohol moiety was possibly biosynthesized from linolenic acid.  相似文献   

6.
Small plot and field experiments on the cultivation of the insecticidal pyrethrum plant in England during 1925-37 showed that the plant grew well and produced satisfactory yields of flowers of high pyrethrin content: costings of the field trials, however, showed that the cultivation of the plant was uneconomic. Individual plants grown from seed differed considerably in growth habit and in the pyrethrin content of their flowers.  相似文献   

7.
Pyrethrin II, cinerin II, allethrin II, pyrethrin II isomer, and allethrin II isomer were prepared by esterification of rethrolons with (+)-trans-pyrethric acid and (+)-trans-methyl-2,2-dimethyl-3-(2′-carboxy-l′-propenyl) cyclopropanecarboxylate and their relative toxicities to pyrethrin I, cinerin I and allethrin I against houseflies were measured by counting “mortality” and “knock-down percent”  相似文献   

8.
红火蚁Solenopsis invicta Buren是一种危险性入侵害虫,可对人类健康、农林业生产、公共安全和生态系统产生严重的负面影响。目前,化学农药是防治红火蚁的主要方法。然而,大多数化学农药并不适用于有机农场、水产养殖区等生态敏感区。为筛选出用于生态敏感区红火蚁防治的药剂,本文结合室内和田间试验评估了植物源杀虫剂苦参碱Matrine、鱼藤酮Rotenone和除虫菊素Pyrethrin对红火蚁的防治效果。室内试验结果表明,苦参碱、鱼藤酮和除虫菊素对红火蚁均具有较高的毒性。田间试验表明,25.00 mg/L和12.50 mg/L苦参碱、250.00 mg/L 和125 mg/L鱼藤酮、75.00 mg/L和37.50 mg/L除虫菊素灌巢处理,红火蚁蚁巢减退率分别达到100%、81.25%、87.50%、79.17%、71.73%和66.67%。然而,除25.00 mg/L苦参碱外,其他处理均导致在被灌巢的蚁巢周围短期内出现新蚁巢。灌巢处理后,处理区的蚂蚁多样性指数和均匀度指数升高,优势度指数下降。综上所述,苦参碱、鱼藤酮和除虫菊素适合灌巢处理防治红火蚁,其中0.5%苦参碱可溶性液剂能有效降低红火蚁种群数量,使得蚁巢减退率达100%,同时对本地蚂蚁群落没有负面影响,因此该商品制剂在红火蚁防治方面具有较好的开发潜力。  相似文献   

9.
The impact of treatments with the pyrethrin insecticide Pyrethrum FS and the repellent kaolin product Surround® WP to control the autumn forms of Dysaphis plantaginea Pass. (Hom., Aphididae), a major insect pest of apple, was assessed in 1‐year field experiments in Switzerland. Single and multiple applications of pyrethrin and kaolin were tested at different dates after apple harvesting in autumn 2002 when sexuales of the rosy apple aphid were present. Repeated applications of Surround® WP in autumn significantly reduced the number of females in autumn and, consequently, the number of hatched fundatrices in spring. Single kaolin treatments were less effective. Unexpectedly, neither single nor multiple applications of the contact insecticide Pyrethrum FS had a knock‐down effect on females in autumn. However, pyrethrin significantly reduced the number of hatched fundatrices in spring. Neither pesticide completely controlled the rosy apple aphid but with a more detailed analysis of factors influencing the efficacy of autumn treatments a new approach to control this serious pest could be achieved.  相似文献   

10.
Phytochemistry Reviews - Pyrethrin is a potent biopesticide, a natural mixture of six compounds (pyrethrin I and II, cinerin I and II, and jasmolin I and II), biosynthesized in plants of Dalmatian...  相似文献   

11.
The synergistic action of phenolic lactones on allethrin and pyrethrin were investigated from the mortality of synergized pyrethroids against rice-weevil by petri-dish method.

In the series of α-benzylidene-γ-butyrolactones, (±) hibalactone and α-piperonylidenebutyrolactone were appreciably sy~ergistic on allethrin although less effective than piperonyl butoxide. (±) Hinokinin, 2-piperonylidene-3-piperonyl-l,4-butanediol also showed week activation, but α-benzylidene-, α-anisylidene-, α-veratrylidene-butyrolactone, α-piperonylidenea-α’-piperonyl-tetrahydrofuran, α-trirnethoxybenzylidene-β-trimethoxybenzyl-butyrolactone were not synergistic on the insecticidal action.

In the series of synergized pyrethrin, (±) hibalactone and α-piperonylidene-butyrolactone showed week synergism but the other test compounds showed no appreciable synergism.  相似文献   

12.
研究了微生物群落在实验室培养条件下对不同土壤环境所产生的变化。在实验室中模拟农田环境,并且在农药和无机肥料的影响下,观察土壤中微生物群落60 d内的功能多样性的变化。实验土壤有4种类型:无农药和化肥影响的土壤(S1);有农药杀灭菊酯和甲基托布津的影响(S2);加入(NH_4)_2HPO_4(S3);加入农药杀灭菊酯、甲基托布津和无机化学肥料(NH_4)_2HPO_4(S4)。实验用BIOLOG GN微平板鉴定系统测定四种土壤的颜色平均变化率(AWCD)值,通过比较S1、S2、S3和S4样本在不同培养天数的AWCD-时间曲线,讨论了农药和无机化学肥料对土壤微生物的影响。  相似文献   

13.
The flowers of Pyrethrum (Chrysanthemum cinerariaefolium) are known to contain Pyrethrins that are naturally occurring potential insecticide. Hairy roots were induced from leaves of C. cinerariaefolium using Agrobacterium rhizogenes strain A4. The root clones were characterized in to four groups i.e. thick, unbranched (D2 and D5), thin, highly branched (D3), thick, branched (B2) and thick, highly branched (D1, D6). Six established hairy root clones showed the presence of pyrethrin and were selected for elicitation studies. Growth kinetics studies revealed highest growth index in hairy root clone D1 (592.0) followed by D6 and D3 on dry weight basis after 40 days of culture. The maximum pyrethrin content was found in the clone D3 (7.2 mg/g dw) which is comparable to the flowers obtained from the variety “Avadh”. Hairy root clone D2 (5.2 mg/g dw) and D6 (1.3 mg/g dw) contained pyrethrin but in less amount as compared to clone D3. The PCR analysis showed the presence of rol B and rol C genes in all the six hairy root clones while rol A was detected only in D2 clone. The methanolic extract of D3 clone showed antifungal activities against phytopathogenic fungal strains which were found maximum against Curvuleria andropogonis followed by Colletotrichum acutatum and Rhizoctonia solani. Hairy root clones D2, D3 and D6 were elicited with culture filtrate of endophytic fungus (Fusarium oxysporum) and bacteria (Bacillus subtilis). The culture filtrate (4.0?%v/v) of both the fungal and bacterial origin was found to be effective in enhancing the pyrethrin content in all the tested hairy root clones. Clone D3 showed maximum pyrethrin content on elicitation with F. oxysporum (9.7 mg/g dw) and B. subtilis (9.7 mg/g dw) culture filtrate, which is 32?% higher than the non elicited D3 hairy roots (7.2 mg/g dw). F. oxysporum also enhanced the hairy root growth resulting into the higher biomass yield of D3 (50?%) and D2 (76?%) in comparison to control non elicited hairy root clones of D3 and D2, respectively leading to higher pyrethrin yield.  相似文献   

14.
The wheat midge, Sitodiplosis mosellana, is a serious pest of wheat worldwide. In North America, management of S. mosellana in spring wheat relies on the timely application of pesticides, based on midge adults levels caught in pheromone traps or seen via field scouting during wheat heading. In this context, biopesticides can be an effective alternative to pesticides for controlling S. mosellana within an Integrated Pest Management program. A field study using insect pathogenic fungus Beauveria bassiana GHA, nematode Steinernema Jeltiae with Barricade polymer gel 1%, pyrethrin, combined formulations of B. bassiana GHA and pyrethrin, Jasmonic acid (JA) and chlorpyrifos (chemical check) was performed to determine to which extent they affect midge larval populations, kernel damage levels, grain yield, and quality, and the impacts on adult parasitoid Macroglenes penetrans populations. The results indicated that biopesticides JA and S. Jeltiae were the most effective in reducing larval populations and kernel damage levels, and produced a higher spring wheat yield when compared to the water control at both study locations (East Valier and North Valier, Montana, USA). Increased test weight in wheat had been recorded with two previous biopesticides at East Valier but not for North Valier, when compared over water control. These results were comparable in efficacy to the chlorpyrifos. This study also suggested that B. bassiana and pyrethrin may work synergistically, as exemplified by lower total larval populations and kernel damage levels when applied together. This study did not demonstrate the effect of any treatments on M. penetrans populations.  相似文献   

15.
The effect of seven synthetic synergists upon the knockdown speed of four pyrethroids against larvae of the common house mosquito, Culex pipiens pallens Coquillett was evaluated with the bioassay by means of petri dish method previously proposed by the author. The results indicated that six synergists studied, except MGK-F5026, decrease the knock-down speed of pyrethrin, allethrin, bartbrin and dimethrin against mosquito larvae.  相似文献   

16.
Although natural insecticides pyrethrins produced by Tanacetum cinerariifolium are used worldwide to control insect pest species, little information is known of their biosynthesis. From the buds of T. cinerariifolium, we have purified a protein that is able to transfer the chrysanthemoyl group from the coenzyme A (CoA) thioester to pyrethrolone to produce pyrethrin I and have isolated cDNAs that encode the enzyme. To our surprise, the active principle was not a member of a known acyltransferase family but a member of the GDSL lipase family. The recombinant enzyme (TcGLIP) was expressed in Escherichia coli and displayed the acyltransferase reaction with high substrate specificity, recognized the absolute configurations of three asymmetric carbons and also showed esterase activity. A S40A mutation in the Block I domain reduced both acyltransferase and esterase activities, which suggested an important role of this serine residue in these two activities. The signal peptide directed the localization of TcGLIP::enhanced green fluorescent protein (EGFP) fusion, as well as EGFP, to the extracellular space. High TcGLIP gene expression was observed in the leaves of mature plants and seedlings as well as in buds and flowers, a finding that was consistent with the pyrethrin I content in these parts. Expression was enhanced in response to wounding, which suggested that the enzyme plays a key role in the defense mechanism of T. cinerariifolium.  相似文献   

17.
除虫菊发状根的诱导及培养条件优化   总被引:1,自引:0,他引:1       下载免费PDF全文
以除虫菊(Pyrethrum cinerariifolium Trey.)无菌苗为外植体,研究除虫菊发状根的诱导、培养条件优化,并对发状根中的除虫菊素进行检测和生物活性测定。结果显示,乙酰丁香酮能促进除虫菊下胚轴和子叶发状根的诱导,当乙酰丁香酮浓度为150 μmol/L时除虫菊下胚轴和子叶的诱导率为对照的2.29倍和2.66倍,预培养6 d时,下胚轴发状根诱导率为对照的2.25倍,发根农杆菌A4的诱导率均高于ATCC15834,愈伤组织较适合发状根的诱导,愈伤组织侵染后适合在无激素的MS培养基上进行发状根诱导,250 mL三角瓶中添加50 mL MS培养基较适合发状根的生长。对除虫菊发状根进行PCR检测发现,发根农杆菌含有的Ri T-DNA的rolB基因已整合进入发状根基因组中。通过GCMS检测发现,愈伤组织中除虫菊素的6种成分均未检测到,而发状根中检测到瓜菊素Ⅰ、茉酮菊素Ⅰ和茉酮菊素Ⅱ 3种成分,发状根对粘虫的拒食作用明显优于愈伤组织。本研究为通过组织培养方式生产除虫菊素奠定了基础。  相似文献   

18.
The frequency of the L1014 F kdr mutation was determined in 14 field populations of house flies, Musca domestica L., with resistance factors at LD50 for pyrethrin/piperonyl butoxide and bioresmethrin/piperonyl butoxide from 4 to 29 and 2 to 98, respectively. A polymerase chain reaction test for identifying kdr homo- or heterozygote house flies was used to determine the frequency of kdr. The L1014 F allele was found in all populations tested. The frequency of kdr in the field populations was high and varied from 0.46 to 0.99. Eleven of the populations were in Hardy-Weinberg equilibrium, whereas two strains had higher number of heterozygotes than expected, indicating a possible heterozygote advantage. The frequency of kdr was strongly correlated with the reduced mortality observed in the bioassays with pyrethrum and bioresmethrin synergized by piperonyl butoxide. This indicates that kdr is a major mechanism for pyrethroid resistance in these field populations. Five field populations had resistance factors >25 and >10 for bioresmethrin/piperonyl butoxide and pyrethrin/piperonyl butoxide, respectively. The frequencies of kdr in these five populations varied from 0.89 to 0.99. The frequencies of kdr in the field populations showing no or a low level of resistance had frequencies of kdr from 0.46 to 0.75, which indicates that the L1014 F kdr allele is a fully recessive genetic trait in house flies. We have shown that the molecular diagnostic PASA method to determine the resistance phenotypes and the frequency of kdr is a powerful tool, which could be used to get information to make recommendations about pest and resistance management.  相似文献   

19.
Penetration of topically-applied pyrethrin I into adult male American cockroaches (Periplaneta americana L.) and its subsequent distribution within the insects was studied microchemically and biologically. After applying an LD95 (0.5 g per insect), pyrethrin I was lost from the surface of the insects at a rate diminishing with time; 20% of the dose applied penetrated during the first hour, but elimination limited the amount found inside the insects to a maximum of 13%. The amount inside the insects increased for an hour after dosing, when symptoms of poisoning had become severe, but then remained steady until the end of the test, 48 hrs after dosing.Pyrethrin I sorbs strongly but reversibly on insect solids from aqueous solution, and at equilibrium is distributed between solids and solution in the ratio 3 × 104: 1. This ratio would give a concentration of only 4 × 10–11 M of pyrethrin I in the haemolymph of insects poisoned with an LD95 of the insecticide, but solids in the haemolymph would increase its pyrethrin I content and speed the spread of the insecticide from cuticle to nervous system. Chemical tests able to detect pyrethrin I at concentrations of 2×10–8 M failed to show its presence in the haemolymph of poisoned cockroaches, but the haemolymph caused symptoms resembling those of pyrethroid poisoning when applied to nerve preparations from normal cockroaches.Although pyrethrin I at 4 × 10–11 M in the haemolymph of cockroaches treated topically with LD95s of the insecticide seems too dilute to have produced the symptoms observed in their nervous systems, the results of additional tests did not support the alternative suggestion that the insecticide reached the nervous system by spreading over the cuticle and through the tracheal system. Larger concentrations of pyrethrin I occurring locally in the haemolymph near the nervous system during the early stages of poisoning may explain the anomaly.
Résumé La pénétration d'une application topique de pyrethrine I chez le mâle adulte de Periplaneta americana et sa distribution ultérieure dans l'organisme est étudiée microchimiquement et biologiquement. Après application d'une dose égale à la DL 95 (0,5 g par insecte), la pyrethrine I est absorbée à la surface de l'insecte à un taux décroissant avec le temps; 20% de la dose appliquée pénètre durant la 1ère heure, mais l'élimination limite la quantité trouvée dans l'organisme à un maximum de 13%. La quantité trouvée dans l'organisme s'accroît pendant la 1ère heure après l'intoxication, quand les symptômes de l'intoxication deviennent importants, puis reste stationnaire jusqu'à la fin du test, soit 48 heures après l'intoxication.La pyrethrine I s'absorbe fortement mais réversiblement sur la phase solide de l'insecte, à partir de la solution aqueuse et le coefficient de partition est de 3×104: 1. Ce coefficient donnarait une concentration de pyrethrine I de seulement 4 × 10–11 M dans l'hémolymphe des insectes intoxiqués à la DL 95, mais la phase solide de l'hémolymphe augmenterait sa teneur en pyrethrine I et accélérerait la vitesse de pénétration de l'insecticide, de la cuticule vers le système nerveux. Des tests chimiques capables de déceler la pyrethrine I à la concentration de 2×10–8 M n'ont pu établir sa présence dans l'hémolymphe des blattes intoxiquées, mais cette hémolymphe provoque des symptômes analogues à ceux de l'intoxication par les pyrethrines, quand elle est appliquée à des préparations nerveuses de blattes nonintoxiquées.Quoique la pyrethrine I à la concentration de 4 × 10–11 M dans l'hémolymphe de blattes traitées localement à la DL 95 de cet insecticide, semble trop diluée pour produire les symptômes observés dans le système nerveux, des résultats supplémentaires n'ont pas autorisé une autre hypothèse, à savoir que l'insecticide atteindrait le système nerveux via la cuticule et le système trachéen. Des concentrations plus fortes de pyrethrine I, localisées près du système nerveux pendant les premiers stades de l'intoxication pourraient expliquer cette anomalie.
  相似文献   

20.
5种生物杀虫剂对4种天敌昆虫的安全性评价   总被引:1,自引:0,他引:1       下载免费PDF全文
【目的】生物杀虫剂及天敌昆虫的应用是绿色防控的发展方向,但有关生物杀虫剂对天敌昆虫的安全性尚不明确。研究生物杀虫剂对天敌昆虫的影响可以为更好地协调使用生物杀虫剂和天敌昆虫提供理论依据。【方法】在实验室条件下采用药膜法和滤纸膜片法测定了5种生物杀虫剂(苦参碱、桉油精、鱼藤酮、除虫菊素、橄榄鲨)在田间推荐使用浓度下,对4种天敌昆虫(丽蚜小蜂、东亚小花蝽、食蚜瘿蚊、巴氏新小绥螨)的致死率。【结果】除虫菊素对丽蚜小蜂、东亚小花蝽、巴氏新小绥螨的影响较大,致死率均达到100%;鱼藤酮对丽蚜小蜂、食蚜瘿蚊、巴氏新小绥螨的影响均较大,致死率在98.65%以上;橄榄鲨对丽蚜小蜂、东亚小花蝽、食蚜瘿蚊的影响较小,致死率均小于30%;苦参碱对丽蚜小蜂的影响最大,致死率达100%,对食蚜瘿蚊和巴氏新小绥螨的影响较小,致死率分别为15.56%和15.91%;桉油精对巴氏新小绥螨的影响最大,致死率达100%,对东亚小花蝽和食蚜瘿蚊的影响较小,致死率分别为15.91%和6.67%。【结论】这5种生物杀虫剂中,橄榄鲨对丽蚜小蜂、东亚小花蝽、食蚜瘿蚊安全,桉油精对东亚小花蝽、食蚜瘿蚊安全,苦参碱对食蚜瘿蚊、巴氏新小绥螨安全,鱼藤酮对东亚小花蝽安全,除虫菊素对食蚜瘿蚊安全。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号