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1.
在实验室内用5％增效浏阳霉素乳油1000倍液防治截形叶螨,24小时后的死亡率为95.5％。对三氯杀螨醇有较强抗性的二斑叶螨和朱砂叶螨,48小时后的死亡率也达90％左右。浏阳霉素对3种叶螨均无杀卵作用,但施药5～6天后,对初孵幼螨仍能杀死90％以上。低温能降低浏阳霉素的药效。在温室中施药一周后。对二斑叶螨的雌成螨无残效,但幼螨和前若螨的死亡率可达97.4％。以磷酸兰苯酯作增效剂的浏阳霉素比亚磷酸三苯酯作增效剂的药效好。在同一剂量下,对二斑叶螨的死亡率分别为98.2％和53.4％。5％浏阳霉素的1000倍液对智利植绥螨成螨的生存率、在叶上的定居率及着卵量均无影响。在温室栽培月季上喷药1次防治二斑叶螨,36天后防治效果仍保持在99％,而用三氯杀螨醇和敌敌畏防治,施药一周后需再次防治。 相似文献
2.
The activities of the chitin synthesis inhibitors, diflubenzuron and PH 60–38, against Spodoptera littoralis larvae were assayed by feeding treated alfalfa or poisoned wheat bran baits, by allowing the larvae to imbibe sucrose-containing aqueous dispersions of the compounds, and by injection into larvae. PH 60–38 was less active than diflubenzuron. On alfalfa, diflubenzuron had to be fed for at least 2 days to prevent formation of normal pupae and emergence of adults. For very big (480–540 mg) larvae, feeding diflubenzuron at concentrations of 50 mg/litre for 2 days or 2.5 mg/litre for 3 days prevented adult emergence. For 200–250 mg larvae, this was achieved by feeding concentrations of 100 mg/litre for 2 days, 5 mg/litre for 3 days or 3.5 mg/litre for 4 days. In all larvae > 150 mg, mortality in feeding experiments occurred in the prepupal or the pupal stage. Only with 30–50 mg and 100–150 mg larvae was there considerable mortality during moults between larval instars, the larvae being unable to liberate themselves from the old larval skins and head capsules. Diflubenzuron incorporated into wheat bran baits at concentrations of from 2.5 to 10 000 μg/g killed approximately 70–90% of the insects. When imbibed, diflubenzuron was much less toxic as a wettable powder than as a liquid formulation but the two formulations were equitoxic when injected into the larvae. 相似文献
3.
三氯杀螨砜对苹果叶螨作用方式及其田间应用技术研究 总被引：1，自引：0，他引：1
以三氯杀螨砜药液处理苹果叶螨 ,结果表明 ,该制剂对卵若 (幼 )螨表现出较高的杀灭活性 ,但对成螨的杀灭活性低。进一步研究发现 ,该制剂能有效抑制雌成螨生殖力 ,田间应用虽不能迅速杀死成螨 ,但能逐渐压低螨口密度 ,与甲氰菊酯混用可显著提高速效 ,达到理想效果 相似文献
4.
A field-collected strain (MR-VL) of the two-spotted spider mite, Tetranychus urticae Koch, exhibited strong resistance to bifenthrin, dicofol and fenbutatin oxide in comparison with a susceptible laboratory strain (LS-VL). The MR-VL strain was screened for cross-resistance with several currently used acaricides. Cross-resistance was detected with clofentezine (RR = 2631), dimethoate (RR = 250), chlorfenapyr (RR = 154), bromopropylate (RR = 25), amitraz (RR = 17), flucycloxuron (RR = 15) and azocyclotin (RR = 7). Abamectin, acequinocyl, bifenazate, tebufenpyrad and spirodiclofen did not show any signs of cross-resistance. Enhanced detoxification by increased activity of mono-oxygenases (MO) and esterases is at least partially responsible for the observed resistance and cross-resistance. MO assays with 7-ethoxycoumarin (7-EC) were optimised and 7-ethoxy-4-trifluoromethylcoumarin (7-EFC), a new MO-substrate, was evaluated for the first time in T urticae and proved to be a good alternative to 7-EC. Approximately 3- and 4-fold higher MO activity was detected with 7-EFC and 7-EC respectively in the MR-VL strain. Kinetic parameters of general esterase assays with 4-nitrophenyl acetate and 1-naphthyl acetate as substrate indicated that more esterases were present in the MR-VL strain. A first attempt was made to classify the esterases present in T urticae. Acetyl-, aryl- and carboxyl-esterases were detected with the use of inhibitors after separation by native PAGE. Glutathione-S-transferases did not seem to play any role in the observed resistance and no differences were detected when the general oxidative capacities of the two strains were compared. 相似文献
5.
BACKGROUND: Diaphorina citri populations in Florida are developing resistance to commonly used neurotoxic insecticides. Alternatives to neurotoxins, such as insect growth regulators, are needed to control this season-long subtropical pest to prevent or delay development of insecticide resistance. In the present investigation, two insect growth regulators (IGRs), buprofezin and diflubenzuron, were evaluated against various developmental stages of D. citri. RESULTS: The 0–1-day-old D. citri eggs were more susceptible to buprofezin and diflubenzuron than the 3–4-day-old eggs. Adult emergence was completely suppressed by treating first- or third-instar nymphs with buprofezin or diflubenzuron at 30–240 or 23–184 µg mL−1 rates respectively. Treatment of fifth-instar nymphs with diflubenzuron at a rate of 184 µg mL−1 and with buprofezin at 30–240 µg mL−1 rates resulted in approximately 20 and 15–80% reductions in adult emergence respectively. The mean number of eggs per plant was reduced at 5 days after topical treatment with diflubenzuron. Mean egg hatch per plant was reduced at 5 and 6–15 days after topical treatments with buprofezin and diflubenzuron respectively. CONCLUSION: Buprofezin and diflubenzuron effectively suppressed D. citri adult emergence. D. citri were more susceptible as early (first–third-instar) than late (fifth-instar) nymphs. Both IGRs inhibited egg production and egg hatch. Reduction in the number of subsequent offspring suggests reduced vertical transmission of Candidatus Liberibacter asiaticus, the pathogen thought to cause citrus greening disease. The present results indicate that both IGRs tested here should be effective tools for rotation in insecticide-based D. citri management programs. Copyright © 2012 Society of Chemical Industry 相似文献
6.
7.
Fenpyroximate resistance in Tetranychus urticae (Acari: Tetranychidae): cross-resistance and biochemical resistance mechanisms 总被引：1，自引：0，他引：1
A field colony of the Two-spotted spider mite, Tetranychus urticae (Koch), resistant to fenpyroximate was further selected with fenpyroximate 5SC for 20 generations at a selection pressure of 30-50% mortality (designated as FR-20 strain). Resistance and cross-resistance levels of the FR-20 strain to 18 acaricides were determined using a spray method. The FR-20 strain was extremely resistant to fenpyroximate [resistance ratio (RR) 252]. The strain exhibited extremely strong positive cross-resistance to acrinathrin (RR 196), and high levels of resistance to benzoximate (RR 55) and propargite (RR 64). Moderate levels of cross-resistance (RR 11-40) to abamectin, fenbutatin oxide, fenpropathrin, pyridaben, pyridaben + bifenthrin and tebufenpyrad were observed. The FR-20 strain showed low levels of resistance (RR < 10) to azocyclotin, bromopropylate, chlorfenapyr, chlorfenapyr + bifenthrin, chlorfenapyr + pyridaben, dicofol, fenazaquin and milbemectin. Synergist experiments with different metabolic inhibitors revealed that piperonyl butoxide had the greatest effect on the efficacy of fenpyroximate, followed by iprobenfos and triphenyl phosphate. In a comparative assay with detoxifying enzymes, the FR-20 strain showed 2.5-fold higher activity in p-nitroanisole-O-demethylation, and 2.5- and 2.2-fold higher activities in alpha- and beta-naphthyl acetate hydrolysis, respectively. These results suggested that enhanced activities of both mixed-function oxidases and esterases likely contribute to the fenpyroximate resistance of the FR-20 strain of T urticae. 相似文献
8.
Diflubenzuron, PH 60–43, PH 60–45, penfluron(PH 60–44) and triflumuron were assayed by a dipping technique for their toxicity toEarias insulana (Boisd ) eggs of different age Testing at a screening concentration of 0 1% a 1 showed that diflubenzuron, triflumuron and PH 60–43 were highly active, whereas PH 60–44 and PH 60–45 were nearly inactive With triflumuron the mortality of 0-1-day-old eggs was >90% even at 0 005%, at 0 001% it was 50% In 1-2-day-old eggs, a >90% kill was obtained even at 0 0005%, whereas at 0 00025% it was 86% PH 60–43 was also highly active, at 0 01% the kill of 0-1-day-old eggs was >90% Again, this rate of kill was obtained with 1-2-day-old eggs at a still lower concentration, 0 005% Both compounds were inactive against 2-3-day-old eggs, even at 0 1% 相似文献
9.
Resistance against dicofol was investigated in the carmine spider mite, Tetranychus cinnabarinus. Higher resistance levels were detected by leaf residual bioassays than by topical bioassays, both done using a Potter spray tower, in almost all populations of T cinnabarinus examined from Antalya, Turkey. For instance, the resistance level at LC95 was 17.5‐fold in topical bioassays but 58.9‐fold in leaf residual bioassays for the population collected from greenhouses in the Topçular district. There were differences of resistance levels at LC95, ranging between 2.6‐ and 23.9‐fold using topical bioassays and between 5.0‐ and 58.9‐fold in residual bioassays, in populations collected from greenhouses from various districts. Populations from cotton showed lower resistance levels against dicofol than populations from greenhouses. Resistance to dicofol at LC50 as indicated by topical and residual bioassays increased 19.7‐ and 100.7‐fold, respectively, in a colony from the laboratory strain of T cinnabarinus selected with dicofol alone for 16 cycles. However, the dicofol resistance at LC50 increased 19.4‐ and 52.0‐fold in another colony selected in rotation with dicofol and tetradifon for six and eight cycles, respectively. The changes in resistance to dicofol 5 months after the selection ceased were as follows: in the colony selected for dicofol alone, using topical and residual bioassays, the resistance levels at LC50 decreased to 11.7‐ and 99.1‐fold, respectively, and in the colony selected in rotation with dicofol and tetradifon to 10.8‐ and 15.8‐fold, respectively. © 2001 Society of Chemical Industry 相似文献
10.
Robert F. Ker 《Pest management science》1978,9(3):259-265
Cuticle consists of chitin microfibrils embedded in a matrix composed largely of hydrated proteins. The effect of diflubenzuron, an inhibitor of chitin synthetase, on the deposition of both these components is reviewed. The polymerisation reaction is but one step in the pathway leading to chitin microfibrils. Possibly interactions to other steps in the pathway serve to enhance the consequences of the inhibition. Such enhancement could help to explain the abrupt changes in the rate of chitin synthesis that can be observed as diflubenzuron is cleared from epidermal cells. Cuticle proteins differ widely in their ability to form a stable layer when chitin is largely absent. In the most stable regions, diflubenzuron has no effect on the amount or nature of the proteins deposited. In contrast, there are many regions where the deposition of solid cuticle is stopped, presumably because the proteins involved cannot form a coherent layer. Intermediate degrees of stability are found. There is an association between the regions of stability and those of high sclerotisation; though sclerotisation often takes place long after deposition. Even when the protein layer is fairly stable it may not be deposited in a regular manner. This statement is illustrated by electron micrographs of cuticle from the hind tibiae of adult locusts. These micrographs also show that diflubenzuron can affect epidermal cells. In normal cells the plaques are in contact with the newly secreted cuticle; they are still present but this contact is not maintained after treatment with diflubenzuron. 相似文献
11.
The chitin biosynthesis inhibitor diflubenzuron and its analog BAY SIR 8514 are equitoxic for eggs ofSpodoptera littoralis. BAY SIR 8514 residues on alfalfa fed toSpodoptera larvae were more toxic than diflubenzuron residues, whereas BAY SIR 8514 topically applied to these larvae was consistently twice as toxic as diflubenzuron, according to different criteria. 相似文献
12.
The chitin precursor [14C] N-acetylglucosamine injected into the haemolymph of Spodoptera littoralis (Boisduval) larva was incorporated into the chitin exponentially with time. When caterpillars were injected with precursor at the commencement of feeding on acylurea-treated leaf discs, flufenoxuron, teflubenzuron and diflubenzuron were found to be equally effective inhibitors of chitin synthesis, measured after 21 h. The dose response curves by feeding are not parallel, indicating that the relative potency of the compounds will vary across the dose range. When chitin precursor was injected simultaneously with topically applied diflubenzuron, flufenoxuron or teflubenzuron, all three acylureas were found to be equally effective as inhibitors of chitin synthesis when measured after five hours. The I50values (50% inhibition of chitin synthesis) were not significantly different; average 600 ng, compared with LD50values (50% lethal dose) of ～ 13 ng for flufenoxuron and teflubenzuron but 130 ng for diflubenzuron (topical application). Injection of precursor 24 h after topical application of insecticide gave an I50value which had dropped 670- and 150-fold for flufenoxuron and teflubenzuron respectively but only 20-fold for diflubenzuron. It is postulated that the reason for the low increase in diflubenzuron effectiveness with time was due either to less diflubenzuron than flufenoxuron reaching the site of action, or more probably, a faster rate of metabolism and excretion for diflubenzuron. The lower toxicity of diflubenzuron compared with flufenoxuron and teflubenzuron may not be due to any inherent differences in biochemical effectiveness, but rather to different penetration/metabolism properties. 相似文献
13.
The chitin synthesis inhibitor diflubenzuron, applied as a wettable powder spray to woven polypropylene at 100–500 mg m?2, was effective against Dermestes maculatus De Geer for at least 12 weeks. D. maculatus was unable to develop on ox hide dipped in a suspension of diflubenzuron (125 mg litre?1), or on fishmeal dusted at 1–10 mg of active ingredient kg?1. Diflubenzuron prevented the development of infestations of Callosobruchus maculatus (L.) on peas and of Acanthoscelides obtectus (Say) on beans dusted at 1–5 mg kg?1. The compound was also very effective against early instar larvae of Trogoderma granarium Everts on wheat. The persistence and activity of diflubenzuron at low dosage rates against D. maculatus appear to justify larger scale trials. 相似文献
14.
Susan A. Lee Barry S. Clarke Donald W. Jenner Francis A. Williamson 《Pest management science》1990,28(4):367-375
Flufenoxuron (“Cascade”) is a novel acylurea with acaricidal and insecticidal properties. It acts in a similar manner to diflubenzuron (DFB) by impairing chitin incorporation into insect cuticle. Chitin can be localised cytochemically using the lectin, wheat germ agglutinin (WGA), which binds specifically to N-acetylglucosamine-containing polymers. WGA adsorbed to monodisperse colloidal gold (WGA-gold) was used as an electron-dense marker for localising chitin in the cuticle of sixth-instar Spodoptera littoralis. In the cuticle of control insects, the deposition zone and endocuticle were heavily labelled. In flufenoxuron- and DFB-treated insects, only the endocuticle (formed before treatment) was labelled, the deposition zone being devoid of label. These results show that flufenoxuron and DFB act in similar manner in reducing chitin incorporation in the cuticle of S. littoralis. 相似文献
15.
Abstract Penfluron and diflubenzuron, both chitin synthesis inhibitors known to be highly effective against nymphs of Poekilocerus pictus (F.), were tested against the adult for their possible effects upon reproduction. These compounds were found to have the maximum effect, when no eggs were laid, if both sexes were treated. The eggs of treated males × untreated females did not hatch and those of treated females × untreated males gave rise to nymphs which died before reaching maturity. 相似文献
16.
三氟氯氰菊酯和甲氰菊酯对二点叶螨生命活力及繁殖力的影响 总被引：3，自引：1，他引：3
采用室内盆栽和叶盘饲养二点叶螨的方法,测定了三氟氯氰菊酯和甲氰菊酯不同浓度对二点叶螨的生命活力和繁殖力的影响。结果表明:分别用三氟氯氰菊酯10和20mg/L在二点叶螨第Ⅰ若螨期处理后,其成螨寿命、产卵量和卵的孵化率分别比对照增加19.4％和14.0％、41.1％和36.8％以及159.1％和107.3％;当分别用甲氰菊酯7.5和15mg/L在二点叶螨第Ⅰ若螨期处理后,其成螨寿命、产卵量和卵的孵化率分别比对照增加24.7％和23.7％、17.1％和9.21％以及174.2％和141％。用三氟氯氰菊酯20mg/L和甲氰菊酯15mg/L分别处理雌成螨后,其产卵量分别比对照增加24.6％和70.2％。在盆栽菜豆苗上以若螨为主的二点叶螨种群,在用三氟氯氰菊酯10、20mg/L处理后的第7d,其各螨态(成螨、幼若螨和卵)的增长指数分别为3.39和3.68、2.37和4.76、2.58和4.38;用甲氰菊酯7.5、15mg/L处理是3.74和4.82、3.22和4.00、2.30和3.75,均高于同期对照。三氟氯氰菊酯和甲氰菊酯对雌成螨和卵的数量明显增加,对害螨的发生有刺激作用。 相似文献
17.
The increase in cuticle thickness with age of fifth instar larvae of Pieris brassicae (L.) was measured microscopically. The injection of a lethal dose of either Polyoxin D or diflubenzuron revealed total inhibition of cuticular growth and caused comparable abnormalities in the cuticles.In a further experiment [14C]glucose was injected along with Polyoxin D into Pieris brassicae and the incorporation of radioactivity into various tissue fractions was measured. This revealed that the impairment of cuticular growth was due to inhibition of chitin synthesis.With the methods used the effects of Polyoxin D and two benzoylphenylurea insecticides appeared to be the same. 相似文献
18.
The chitin synthesis inhibitors diflubenzuron and teflubenzuron have recently become ineffective for the control of Spodoptera exigua in floricultural crops. An extended laboratory test with second-instar larvae of S. exigua on Vicia faba plants was carried out to determine the influence of synergists on the biological activity of three benzoylphenyl ureas (BPUs). The co-application of piperonyl butoxide, an oxidase inhibitor, did not increase the activity of diflubenzuron, teflubenzuron or hexaflumuron. The best results were obtained with diethyl maleate, for suppressing glutathione S-transferase activity, and with dimethoate, as a hydrolase inhibitor. A joint application of diflubenzuron (at a concentration which resulted in 43% survival) with diethyl maleate or dimethoate gave only 6.2 and 8.9% surviving larvae, respectively. In addition, development to fourth-instar larvae was inhibited. The more stable teflubenzuron was synergized by both compounds to a much lesser extent than diflubenzuron. None of the synergists had a significant effect on the activity of hexaflumuron, which was the most potent insecticide of the three BPUs tested against S. exigua. 相似文献
19.
J. E. Cranham 《Pest management science》1972,3(3):271-276
Formetanate was found to be somewhat less effective on three strains of Panonychus ulmi (Koch) resistant to organophosphorus compounds (O.P.'s), and on two others multi-resistant to O.P.'s and tetradifon, than on susceptible mites; the LC50's in tests on larvae or adult mites were two to three times greater. Chlorphenamidine was as effective on O.P.-resistant mites as on susceptibles; but on the multi-resistant strains it was more effective, the ratio of LC50's, R/S, in assays on larvae being ×0.37. However, it has not been shown that resistance to tetradifon confers true (pleiotropic) negative cross-resistance to chlorphenamidine. 相似文献
20.
CME 134, a new benzoylphenyl urea chitin synthesis inhibitor, was less active than diflubenzuron and BAY SIR 8514, when tested againstSpodoptera littoralis eggs by a dipping method. AgainstS. littoralis larvae the compound was tested by feeding treated alfalfa, topical application and contact with crystalline residues on glass, followed by observation until the adult stage. With both 200–250 and 360–440-mg larvae 100% mortality was obtained by one-day feeding of alfalfa treated with 0.15 ppm a.i. Topical application to 100- and 200-mg larvae showed CME 134 to be about five and nine times more active than BAY SIR 8514 and diflubenzuron, respectively. These differences were even much greater in the contact tests. Cotton field plots were sprayed with either CME 134 or diflubenzuron formulations, leaves were collected at different intervals and fed for one day toS. littoralis larvae in the laboratory. 0.0009% a.i. CME 134 residues gave complete kill of 30–50-mg larvae after 5 and 20 days, and 86% kill after 28 days of aging. With 0.003 and 0.009% a.i., complete kill was obtained in 200–250-mg larvae until 50 days after spraying. 相似文献