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 15 毫秒
1.
对甜菜夜蛾的毒力测定结果表明,多杀菌素能显著降低其初孵幼虫的存活率、成虫的产卵量和成虫寿命。经6.25 μg/mL药液处理的卵,其初孵幼虫存活率仅为7.48%,而对照则为76.72%;取食12.50 μg/L药液的成虫,其产卵量和成虫寿命仅为取食蜂蜜水的1/6和1/2.5。随虫龄的增加,甜菜夜蛾幼虫对多杀菌素的敏感性显著降低,3龄、4龄幼虫的敏感性仅为2龄幼虫的1/9和1/16,且增效剂氧化胡椒基丁醚(PBO)与磷酸三苯酯(TPP)表皮点滴处理不表现增效作用。多杀菌素对甜菜夜蛾卵的孵化率、蛹重以及蛹的羽化率没有明显影响。亚致死剂量处理3龄幼虫后,其体内超氧化物歧化酶、过氧化氢酶和过氧化物酶等主要保护酶系的活性在处理后0~24 h与对照差异不明显,保护酶系与甜菜夜蛾对多杀菌素敏感性之间没有明显关系。  相似文献   

2.
Susceptibility to spinosad of western flower thrips (WFT), Frankliniella occidentalis (Pergande), from south-eastern Spain was determined. LC(50) values of the field populations without previous exposure to spinosad collected in Murcia in 2001 and 2002 ranged from 0.005 to 0.077 mg L(-1). The populations collected in Almeria in 2003 in greenhouses were resistant to spinosad (LC(50) > 54 mg L(-1)) compared with the authors' highly susceptible laboratory strain. The highly sensitive laboratory strain leads to very high resistance ratios for the field populations (>13 500), but these ratios do not necessarily mean resistance problems and control failures (spinosad field rate 90-120 mg L(-1)). The populations collected in Murcia from some greenhouses in 2004 were also resistant to spinosad (RF > 3682). Spinosad overuse, with more than ten applications per crop, produced these resistant populations in some greenhouses. Spinosad showed no cross-resistance to acrinathrin, formetanate or methiocarb in laboratory strains selected for resistance towards each insecticide. Correlation analysis indicated no cross-resistance among spinosad and the other three insecticides in 13 field populations and in nine laboratory strains. The synergists piperonyl butoxide (PBO), S,S,S-tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM) did not enhance the toxicity of spinosad to the resistant strains, indicating that metabolic-mediated detoxification was not responsible for the spinosad resistance. These findings suggest that rotation with spinosad may be an effective resistance management strategy.  相似文献   

3.
The toxicity of the naturally derived insecticide spinosad was tested against the gypsy moth, Lymantria dispar. Bioassays using red oak leaf disks, treated with spinosad in a Potter spray tower, yielded an LC50 value of 0.0015 µg AI cm−2 (3‐day exposure; 13‐day evaluation; 2nd instar larvae). Applied to foliage to run‐off in the laboratory (potted red oak seedlings) and the field (4 m‐tall birch trees), spinosad effectively controlled 2nd instar larvae at concentrations ranging from 3 to 50 mg litre−1. Toxicity in the laboratory, and efficacy and persistence in the field, were comparable to those achieved with the insecticide permethrin. Laboratory studies supported field observations that control was achieved in part by knockdown due to paralysis. In addition, laboratory results demonstrated that crawling contact activity may play an important role in field efficacy; 50% of treated larvae were paralyzed 16 h after a 2‐min crawling exposure to glass coated with a 4 mg litre−1 spinosad solution. © 2000 Society of Chemical Industry  相似文献   

4.
Laboratory studies were conducted to determine the effect of the naturally derived compound spinosad on Ceratitis capitata Wied. (Diptera, Tephritidae). The organophosphate fenthion was used as a standard. Direct dose-dependent mortality and reduced fecundity were observed in oral treatment of adults with spinosad. The LC90 values 14 h and seven days after treatment were 19·50 and 0·49 mg litre−1 respectively. Fenthion was less active (the LC50 eight days after treatment was 1·17 mg litre−1) and did not affect the fecundity of the fly. Adults were also very susceptible to spinosad and fenthion via residual contact. For spinosad, 100% mortality was recorded 48 h after treatment for a dose of 10 mg litre−1. Spinosad was more effective than fenthion in suppressing larval development when neonate larvae were reared on treated diet supplemented with a range of concentrations from 0·02 to 0·83 mg kg−1 diet. Last-instar larvae were much less susceptible to spinosad or fenthion when exposed via dipping or when they pupated in treated medium and both products had similar performance. A lack of ovicidal activity was observed in direct egg-treatments with spinosad but significant reductions from 1 mg litre−1 onwards were recorded for fenthion.  相似文献   

5.
The response to azinphos-methyl of different life-stages of the codling moth Cydia pomonella (L.) was studied. A similarity in response to azinphos-methyl (LC(50), LC(90)) was observed in neonate larvae obtained from the first and second generations of field populations. Mortality rates for neonate larvae of a field population cross-bred with a laboratory colony were lower (by a factor of 1.2-2.2) in comparison with field neonate larvae. The mortality rate of larvae from a laboratory colony exposed to artificial diet containing azinphos-methyl gradually decreased at older instars. The mortality rates of fifth-instar larvae were remarkably low when exposed to artificial diet mixed with azinphos-methyl or when topically treated with the insecticide. One- to three-day-old females were more sensitive than males of the same age, whereas the opposite was observed in 14-to 17-day-old adults. Mortality rates of 14- to 17-day-old adults were higher than those under 10 days old. No significant difference in sensitivity to the organophosphorus compound was noticed between the sexes of 7- to 10-day-old adults. Neonate larvae of the codling moth can serve as a target life-stage for various groups of pesticides, and the importance of using such a stage as a standardized methodology for monitoring resistance in the codling moth is discussed.  相似文献   

6.
Spinosad, a reduced-risk commercial insecticide derived from a bacterial fermentation product, possesses both contact and oral toxicities against insects. Contact toxicity of spinosad to adults of Rhyzopertha dominica (F), Sitophilus oryzae (L), and Tribolium castaneum (Herbst) was evaluated by exposure for 24 or 48 h to treated glass Petri dishes. Adults were exposed to different deposits (0.001-0.79 mg cm(-2)) of spinosad in 24-h tests and to deposits of 0, 0.0016 and 0.016mg cm(-2) in 48-h tests. Rhyzopertha dominica was most susceptible to spinosad in 24- and 48-h tests, followed by S. oryzae, and T. castaneum. The 24-h LD50 values were 0.0004, 0.077 and 0.189mg cm(-2) for R. dominica, S. oryzae, and T. castaneum, respectively. All R. dominica adults were dead following 48 h exposure to both spinosad deposits, whereas mortality of S. oryzae and T. castaneum ranged from 10 to 85% and 12 to 48%, respectively. Rhyzopertha dominica, T. castaneum, and O. surinamensis adults were exposed for 14 days to whole wheat, cracked wheat and wheat flour treated with 0, 0.1 and 1.0 mg kg(-1) of spinosad. Rhyzopertha dominica adults were highly susceptible to spinosad, followed by O. surinamensis and T. castaneum. Immatures (eggs and larvae) of T. castaneum and O. surinamensis exposed for 14 days were more susceptible on spinosad-treated whole wheat than on treated cracked wheat and wheat flour. This is the first report documenting contact activity of spinosad, and the effect of grain condition on spinosad toxicity, to stored-product insects.  相似文献   

7.
多杀菌素微球制备关键工艺研究:Ⅱ   总被引:4,自引:3,他引:1  
采用乳化-溶剂挥发法,以聚乳酸(PLA)为成球材料(壁材)制备了多杀菌素微球。研究了PLA浓度和油/水相体积比对多杀菌素微球制备的影响规律,确定了制备多杀菌素微球的优选配方及工艺条件。制备得到中位径(D50)为12.73 μm、跨距为1.4811、载药量在31%左右、包封率为100.2%、包封产率为89.4%的多杀菌素微球,重复性良好。扫描电镜(SEM)观察结果表明,所得微球为表面较光滑的实心小圆球。差示扫描量热(DSC)分析结果证实,多杀菌素和PLA的确形成了载药微球。室内毒力测定结果表明,自制5%多杀菌素微球悬浮剂与市售2.5%多杀菌素悬浮 剂(菜喜)对小菜蛾Plutella xylostella 2龄幼虫的毒力基本相同,LC50值分别为0.40和0.38 μg/mL。  相似文献   

8.
Every year raw tobacco and manufactured tobacco products are lost to two major storage pests, the cigarette beetle, Lasioderma serricorne (F) and the tobacco moth, Ephestia elutella (Hiibner). Post-harvest management of both insects is achieved through sanitation, insect monitoring and fumigation with phosphine. However, insect resistance to phosphine and control failures have been reported, and fumigants are under constant regulatory pressure. Here we report the evaluation of spinosad, a bioinsecticide derived from the fermentation of the soil micro-organism Saccharopolyspora spinosa Mertz & Yao. Spinosad was first registered in 1997 and is now widely used as a field pest control agent on many crops, including tobacco. The insecticidal activity of the fermentation product (technical spinosad, TS) was measured by diet incorporation assays against L serricorne and E elutella larvae. Mortality levels were determined on newly hatched larvae and over the whole insect life cycle. For both species, no emergence of adult insects was observed in cured tobacco sprayed with 50mg TS kg(-1) and inoculated with eggs or newly hatched larvae. These results indicated that spinosad has potential for the control of both species in stored tobacco, since 100% control of both pests could be achieved at 50 mg TS kg(-1), and with almost full control (90-95%) at 10 mg kg(-1). We also monitored the stability of the product on cured tobacco. The original concentration of the main active component of TS, spinosyn A, did not change significantly over 18 months, indicating no loss of spinosad during a typical leaf storage period of time. Bioassays against larvae confirmed that the bioinsecticidal activity of spinosad was retained.  相似文献   

9.
BACKGROUND: The goal of the research was to gather efficacy data required to introduce reduced-risk insecticides in sustainable control programs for European corn borer, Ostrinia nubilalis Hubner, on potato. RESULTS: Laboratory tests confirmed that sprays of indoxacarb and novaluron at recommended field rates are as effective as spinosad against neonate larvae of O. nubilalis. However, there is evidence that higher rates would enhance the inhibition of chitin synthesis by novaluron. The three insecticides showed ovilarvicidal activity when applied to O. nubilalis egg masses 2 days prior to black head stage. The ovicidal activity of spinosad and novaluron was almost twice that of indoxacarb. At the recommended field rates, the residues of the three insecticides displayed contact toxicity to O. nubilalis larvae. Spinosad residues 16 h old or less provided the highest immediate (24 h after exposure) contact mortality, followed by indoxacarb and then by novaluron. Also, residues of spinosad had faster contact efficacy than indoxacarb, which had faster efficacy than novaluron. CONCLUSION: Spinosad, indoxacarb and novaluron have ovicidal properties, which could enhance O. nubilalis management programs. However, the contact residual toxicity is limited in duration and would likely only play a minor role in O. nubilalis control.  相似文献   

10.
The pine processionary moth Thaumetopoea wilkinsoni Tams is a serious pest on pine trees in southwestern Turkey. The efficacy of a naturally derived insecticide, spinosad, on fourth-fifth instar larvae of T. wilkinsoni was studied under laboratory conditions. The product exhibited strong larvicidal activity and at doses above 5 mg litre(-1) caused > 90% mortality in the fourth-fifth larval stages of the species after 72 h. At 72 h the LD50 and LD90 values were 3.26 and 5.69 mg litre(-1) respectively. The results showed that spinosad is highly effective on T. wilkinsoni larvae.  相似文献   

11.
The development of resistance to an insecticide under various types of application method has yet to be reported in the literature. Five fall armyworm Spodoptera armigera (JE Smith) colonies were reared in a chamber for ten generations before starting topical application bioassays. From each colony, 200-500 third-fourth-instar larvae were fed for 72 h on corn plants sprayed with cypermethrin or spinosad at minimum application rate (20 g ha(-1)) using a small droplet size nozzle XR8001VS (volume median diameter D(v0.5) = 163 microm) or a large droplet size nozzle XR8008VS (D(v0.5) = 519 microm). Surviving larvae were transferred to untreated corn leaves to complete their life cycle. Next-generation third-instar larvae of each colony were topically dosed with technical cypermethrin or spinosad at 1 microL per larva, and mortality was recorded 24 h post-treatment. The results indicated that cypermethrin demonstrated an insecticidal activity greater than that of spinosad, and the cypermethrin regression lines moved to the right faster than those for spinosad, indicating an increased tolerance of cypermethrin. Generally, larvae from all generations (F1-F7) under the XR8008VS treatments were less susceptible to cypermethrin and developed resistance faster and to higher levels than larvae from the XR8001VS treatments. The confidence limits (95%) of LD(50) for all spinosad treatments indicated that there was no significant difference from the LD(50) value of the susceptible reference strain. The results are a first indication that application technology/insecticide reaction may affect the rapidity of resistance development in certain pest/plant scenarios, but field studies are needed to confirm this conclusion.  相似文献   

12.
The influence of post-treatment temperature on the toxicities of two pyrethroids (lambda-cyhalothrin and bifenthrin), a carbamate (methomyl) and a spinosyn (spinosad) to Ostrinia nubilalis (Hubner) larvae was evaluated in laboratory assays. From 24 to 35 degrees C, the toxicities of the pyrethroids decreased 9.5- and 13.6-fold while spinosad toxicity decreased 3.8-fold. The toxicity of methomyl did not change significantly. The results demonstrate that the most effective insecticide against a pest may vary with environmental conditions. In situations where comparable products from multiple insecticide classes are available, temperature should be included as a factor in the decision-making process.  相似文献   

13.
BACKGROUND: Bait-formulated spinosad is currently being introduced for housefly (Musca domestica L.) control around the world. Spinosad resistance was evaluated in a multiresistant field population and strains derived from this by selection with insecticides. Constitutive and spinosad-induced expression levels of three cytochrome P450 genes, CYP6A1, CYP6D1 and CYP6D3, previously reported to be involved in insecticide resistance, were examined. RESULTS: In 2004 a baseline for spinosad toxicity of Danish houseflies where all field populations were considered to be susceptible was established. In the present study, females of a multiresistant field population 791a were, however, 27-fold spinosad resistant at LC50, whereas 791a male houseflies were susceptible. Strain 791a was selected with spinosad, thiamethoxam, fipronil and imidacloprid, resulting in four strains with individual characteristics. Selection of 791a with spinosad did not alter spinosad resistance in either males or females, but counterselected against resistance to the insecticides thiamethoxam and imidacloprid targeting nicotinic acetylcholine receptors. A synergist study with piperonyl butoxide, as well as gene expression studies of CYP6A1, CYP6D1 and CYP6D3, indicated a partial involvement of cytochrome P450 genes in spinosad resistance. CONCLUSION: This study reports female-linked spinosad resistance in Danish houseflies. Negative cross-resistance was observed between spinosad and neonicotinoids in one multiresistant housefly strain. Spinosad resistance involved alterations of cytochrome P450 gene expression. Copyright © 2011 Society of Chemical Industry  相似文献   

14.
The toxicity of spinosad, a new insecticide derived from the bacterium Saccharopolyspora spinosa, was evaluated against susceptible and resistant strains of house fly (Musca domestica L.). Spinosad was highly toxic to house flies based on 72-h LD50 values and the symptoms of poisoning were consistent with a neurotoxic mechanism of action. Spinosad was relatively slow acting, with the maximum toxicity noted at 72 h. Piperonyl butoxide and S,S,S,-tribu-tylphosphorotrithioate synergized the toxicity of spinosad by 3·0- and 1·8-fold, respectively, while diethyl maleate had no significant effect. These results suggest that there is a small degree of monooxygenase-mediated spinosad detoxification in house flies, while hydrolases may be only minimally important and glutathione transferases may have no role. There were no substantial levels of cross-resistance detected, except in the LPR strain where a low 4·3-fold cross-resistance was observed. The cyclodiene-resistant OCR strain was 2·7-fold more sensitive to spinosad than the susceptible strain (CS). These results suggest that cross-resistance may not be a limiting factor for the use of spinosad against house flies. © 1998 Society of Chemical Industry  相似文献   

15.

BACKGROUND

Tuta absoluta (Lepidoptera: Gelechiidae) is difficult to control by means of foliar insecticides, partly because of the endophytic feeding behavior of its larvae. The biopesticide spinosad is applied as a foliar spray for control of T. absoluta and has systemic properties when applied as a soil drench to the growing medium of tomato plants. The aims of this study were to determine the: (i) instar-dependent tolerance of larvae to spinosad; (ii) efficacy of spinosad drench application for the control of larvae; (iii) residual period of systemic activity of spinosad in leaves and fruit after drenching; and (iv) effect of spinosad drenching on tomato plant growth parameters.

RESULTS

The estimated LC50 value (Lethal Concentration at which 50% of the larvae died) differed between instars. The LC50 for second-instar larvae (0.41 ppm) to spinosad was significantly lower than that for third- (0.64 ppm) and fourth-instar (0.63 ppm) larvae. The LC80 value (Concentration at which 80% of the larvae died) for fourth-instar larvae (2.48 ppm) was 2.6- and 1.7-fold higher than that for the second- and third-instar larvae, respectively. The spinosad concentration recorded in leaves at 25 days after treatment (DAT; 0.26 μg g−1) was significantly lower than that in leaves sampled at 3, 10 and 15 DAT. High larval mortalities were, however, recorded for the duration of the experiment, which lasted 25 days (equivalent to one T. absoluta generation).

CONCLUSION

Systemic spinosad effectively controlled T. absoluta larvae over a prolonged period. However, drenching this insecticide violates the recommendation of the Insecticide Resistance Action Committee to avoid treating consecutive insect generations with the same mode of action and can therefore result in the evolution of insecticide resistance. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   

16.
BACKGROUND: Resistance to spinosad and methoxyfenozide has been studied in several insect pests, but there is a lack of information on Spodoptera exigua (Hübner) in Mexico. Therefore, evidence for the development of resistance in this pest to both compounds was examined. The effects of methoxyfenozide on reproductive parameters of S. exigua adults were also determined.RESULTS: Third instars from a field population were exposed for 24 h to the LC(50) of spinosad or methoxyfenozide for over six generations (G(2)-G(7)). No significant reduction in susceptibility to either compound was detected for up to five generations. In G(7), LC(50) values for insects exposed to spinosad and methoxyfenozide were respectively 2.75-fold and 1.25-fold greater than for G(1) larvae. Oral treatment with methoxyfenozide reduced the fecundity and fertility of G(7) adults, confirming sublethal effects on reproduction. Finally, five populations (Se-La Floriza, Se-Lazareto, Se-Bachigualato, Se-Los Agustinos and Se-Villa de Arista) of S. exigua were collected from fields in three states of Mexico for resistance monitoring to spinosad and methoxyfenozide. With the exception of Se-Villa de Arista, the other populations showed significant resistance to spinosad, with resistance ratios between 16- and 37-fold, compared with a susceptible laboratory colony. In contrast, only one population (Se-Lazareto) showed significant resistance to methoxyfenozide (13-fold).CONCLUSION: Resistance management programmes should be established, particularly in areas where S. exigua has developed resistance to spinosad. Copyright (c) 2008 Society of Chemical Industry.  相似文献   

17.
Susceptibility to spinosad (Success®/Tracer®) of beet armyworm (Spodoptera exigua) from the southern USA and Southeast Asia was determined through exposure of second‐ and third‐instar larvae to dipped cotton leaves. LC50 estimates of susceptibility of second‐ and third‐instar larvae of field populations ranged from 0.279 to 6.14 and 0.589 to 14.0 mg spinosad litre−1, respectively. A Thailand population was 22‐ and 24‐fold less susceptible than the six other US field populations evaluated, and 85‐ and 58‐fold less susceptible than a reference laboratory population, respectively. From these results, we initiated experiments to test the hypothesis that the Thailand population was resistant to spinosad. F1 crosses between the resistant Thailand population and a susceptible reference strain yielded individuals that were 22‐fold less sensitive to spinosad than the susceptible parent. This same resistant strain exhibited significantly greater survivorship on plants treated with spinosad in the field. Lastly, selection of an Arizona population resulted in a significant reduction in susceptibility to spinosad, further substantiating the hypothesis of a genetic basis for resistance to spinosad. These findings indicate a vulnerability of this new insecticide to resistance development in beet armyworm and should serve as a warning against excessive use of it. © 2000 Society of Chemical Industry  相似文献   

18.
BACKGROUND: Six sweet cherry (Prunus avium L.) cultivars were tested with GF-120 with spinosad (0.2 g L(-1) spinosad bait) or without it (blank bait) to understand leaf phytotoxicity observed in the field. RESULTS: Spinosad bait and blank bait did not differ significantly with respect to damage observed. Leaf damage was found almost exclusively at the abaxial (lower) surfaces with the doses (0, 17, 20, 25 or 40%) and cultivars tested. The effects of the blank bait on abaxial surfaces increased from 24 to 168 h, and with dose, in terms of the proportion of droplets (0.00, 0.42, 0.52, 0.75 or 0.94) and area (0.0, 18.7, 23.5, 40.5 or 91.6 mm) burned. In addition, chlorophyll was reduced with increasing dose on abaxial surfaces (SPAD = 44.6, 36.1, 34.1, 31.0, 21.5), but not on adaxial (upper) surfaces (SPAD = 44.6, 44.2, 44.0, 44.8, 44.4). The chlorophyll level in undamaged leaves (adaxial surfaces) differed by cultivar. Cherry leaves were less damaged by a 20% bait application in June (0.26) than in July (0.46) and August (0.50). Incidental insect leaf feeding at bait locations occurred at a low rate and was highest on abaxial bait surfaces. CONCLUSIONS: Applying GF-120 to the adaxial leaf surface, or at doses of 相似文献   

19.
Abundance and diversity of arthropods were compared in olive trees treated against the olive fruit fly with spinosad bait sprays and an untreated control, paying special attention to predators and parasitoids. Spinosad bait sprays did not reduce the abundance and diversity of arthropods as a whole in the canopy. However, principal response curve analysis revealed a significant deleterious effect of the treatments on natural enemies in the last of the three years of study. The most affected taxa were Anthocoridae (especially Orius spp.) and Aphelinidae.  相似文献   

20.
BACKGROUND: Spinosad is a biopesticide widely used for control of Frankliniella occidentalis (Pergande). It is reported to be non‐toxic to several predatory mite species used for the biological control of thrips. Predatory mites Typhlodromips montdorensis (Schicha), Neoseiulus cucumeris (Oudemans) and Hypoaspis miles (Berlese) have been used for control of F. occidentalis. This study investigated the impact of direct and residual toxicity of spinosad on F. occidentalis and predatory mites. The repellency of spinosad residues to these predatory mites was also investigated. RESULTS: Direct contact to spinosad effectively reduced the number of F. occidentalis adults and larvae, causing > 96% mortality. Spinosad residues aged 2–96 h were also toxic to F. occidentalis. Direct exposure to spinosad resulted in > 90% mortality of all three mite species. Thresholds for the residual toxicity (contact) of spinosad (LT25) were estimated as 4.2, 3.2 and 5.8 days for T. montdorensis, N. cucumeris and H. miles respectively. When mites were simultaneously exposed to spinosad residues and fed spinosad‐intoxicated thrips larvae, toxicity increased. Residual thresholds were re‐estimated as 5.4, 3.9 and 6.1 days for T. montdorensis, N. cucumeris and H. miles respectively. Residues aged 2–48 h repelled T. montdorensis and H. miles, and residues aged 2–24 h repelled N. cucumeris. CONCLUSION: Predatory mites can be safely released 6 days after spinosad is applied for the management of F. occidentalis. Copyright © 2011 Society of Chemical Industry  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