几种中药材对赤拟谷盗的致死作用及其趋避性研究

用中药材丁香、细辛、陈皮、吴茱萸、花椒、千年健对仓虫赤拟谷盗成虫的致死作用和趋避作用进行了研究。结果表明:6种中药材对赤拟谷盗成虫的致死效果为丁香>细辛>陈皮>吴茱萸>花椒>千年健。当丁香与其他5种药材一起同贮或分别贮存时,丁香里始终不见赤拟谷盗,在千年健里赤拟谷盗分布较多,而在其他几种药材中分布明显减少。各种中药材对拟谷盗的驱虫作用有明显差异。     

Repellancy and contact toxicity of clove bud oil and its constituents against German cockroaches,Blatella germanica (Dictyoptera: Blattellidae), under laboratory conditions

Abstract

The German cockroach, Blattella germanica L. (Dictyoptera: Blattellidae), an invasive pest of human habitats, is distributed throughout the world, except in Antarctica. They have developed resistance against chemical pesticides used for the management of their populations. Numerous essential oils and their constituents have been tested; however, the insecticidal activities of clove bud powder, oil, and their constituents have not yet been tested against the German cockroaches. Thus, in this study, clove bud powder, oil, and their major constituents, eugenol and eugenol acetate, were evaluated for their contact toxicity and repellancy against adult German cockroaches under laboratory conditions. The clove bud powder applied at 30?mg/cm² killed 92% of German cockroaches at 6?hours after treatment (HAT). Similarly, clove bud oil, eugenol and eugenol acetate applied at 4.00?ml/cm² provided 95%, 85%, and 87% German cockroach mortality at 24, 6, and 24 HAT, respectively. At 2.0?ml/cm², clove bud oil repelled 80% of German cockroaches within 30?min. In contrast, eugenol and eugenol acetate repelled 85% at 1.0?ml/cm² and 2.5?ml/cm², respectively, at 0.5 HAT. Based on this study, clove bud powder, oil, eugenol, and eugenol acetate could be environmentally friendly tools for the management of German cockroaches.     

Composition and toxic, repellent and feeding deterrent activity of essential oils against the stored-grain pests Tribolium castaneum (Coleoptera: Tenebrionidae) and Sitophilus oryzae (Coleoptera: Curculionidae)

BACKGROUND: The composition and bioactivity of essential oils from Tagetes terniflora Kunth, Cymbopogon citratus Stapf. and Elyonurus muticus (Spreng) Kuntz were evaluated against stored‐grain pests. RESULTS: Fumigant and contact toxicities were observed with T. terniflora on adults of both pests. In contact toxicity, this oil was less toxic to Tribolium castaneum (Herbst). Essential oils from C. citratus and E. muticus showed contact toxicity on S. oryzae. All essential oils produced: (a) repellency on larvae and adults of T. castaneum and adults of Sitophilus oryzae (L.); (b) post‐ingestive toxicity on T. castaneum larvae and S. oryzae adults and alteration of nutritional index on T. castaneum and S. oryzae adults. Cymbopogon citratus reduced the relative growth rate and the efficiency of conversion of ingested food in T. castaneum larvae. Tagetes terniflora produced a feeding stimulant effect in T. castaneum adults. In addition, they had a feeding deterrent action against S. oryzae adults. The composition of essential oils from C. citratus and E. muticus varied only in one component. CONCLUSION: These results showed that the essential oils from T. terniflora, C. citratus and E. muticus should be studied further for their use in integrated pest management programmes for T. castaneum and S. oryzae control. Copyright © 2011 Society of Chemical Industry     

丁香精油及其与壳聚糖复合物对水果采后病原菌的抑制作用

研究了丁香精油以及丁香精油-壳聚糖复合物对几种水果采后腐烂的主要致病真菌灰霉菌、链格孢,青霉菌、浆孢菌的孢子萌发和菌丝生长的抑制效应,确定其最低抑菌浓度和最低杀菌浓度。结果表明,丁香精油对供试病原菌均有较强的抑制效果,10μL/mL丁香油对4种菌菌丝生长和孢子萌发的抑制率达到85%以上。丁香油-壳聚糖复合物溶液在10μL/mL时(含丁香油有效成分5μL/mL)对4种菌菌丝生长和孢子萌发的抑制率在80%以上,而5μL/mL丁香油对其菌丝生长和孢子萌发的抑制率大都在80%以下,复合物的抑菌效应比含有相同有效浓度的丁香精油抑菌效应有明显提高。     

丁香对赤拟谷盗卵和幼虫的致死作用

在室内条件下,研究了丁香干燥花蕾粉末对赤拟谷盗卵和幼虫的影响。结果表明:丁香对赤拟谷盗卵孵化有明显的抑制作用,对赤拟谷盗幼虫有致死作用并且全部致死时间随着赤拟谷盗幼虫龄期的增大而延长,龄期越小的幼虫其全部致死时间越短。     

Pyrethroid synergism and prevention of emergence inTribolium castaneum andMusca domestica vicina by the insect growth regulator RO 13-5223

Ethyl [2-(4-phenoxyphenoxy)ethyl] carbamate (RO 13-5223) at a dietary concentration of 100 mg kg^-1 synergized the toxicity of thetrans- andcis-isomers of permethrin and cypermethrin in inhibiting the growth (measured as gain in larval weight) ofTribolium castaneum andMusca domestica vicina. With both species the synergism factor forcis-cypermethrin with 100 mg kg^-1 synergist was 1.5- to twofold for RO 13-5223 and about fourfold for piperonyl butoxide. Synergism was more pronounced with first instar than with fourth instarT. castaneum larvae. Methoprene was not a pyrethroid synergist withT. castaneum larvae, so the synergistic effect of RO 13-5223 appears to depend on its structural features and not its insect-growth-regulator activity. Joint application of RO 13-5223 and pyrethroids resulted in a dual effect on bothT. castaneum andM. domestica: increased inhibition of larval growth due to pyrethroid synergism, and progeny suppression — expressed by larval and pupal mortality — due to RO 13-5223 juvenilizing activity.     

The antifeedant effect of some new withanolides on three insect species,spodoptera littoralis,epilachna varivestis andtribolium castaneum

The antifeedant effect of several new withanolides on larvae ofSpodoptera littoralis, Epilachna varivestis andTribolium castaneum was investigated. 2,3-Dihydrowithanolide E (II) was an antifeedant forS. littoralis andE. varivestis; nicalbin A (XIV), and a mixture of withanicandrin (IX) and daturalactone A (X), were active against E. varivestis andT. castaneum. Some activity was shown by 6β,14α,17β,20α_F-tetrahydroxy-1-oxowitha-2,4,24-trienolide (V) againstS. littoralis; 4β,5β-epoxy-6α,14α,17β,20α_F-tetrahydroxy-l-oxowitha-2,24-dienolide (VII) againstE. varivestis andT. castaneum; 5α,6α,-epoxy-14α,17β,20α_F-trihydroxy-1-oxowitha-2,24-dienolide (VI) againstE. varivestis; and nicalbin B (XV) againstT. castaneum.     

Enhancement of the toxicity of methyl bromide toTribolium castaneum adults by its admixture with carbon Monoxide

The effect of methyl bromide in admixture with 20%, 30% and 40% carbon monoxide (CO) onTribolium castaneum adults was tested. The combination of methyl bromide with 20% CO increased the toxicity of CH₃Br 1.4-fold, with 30% CO-1.5-fold, and with 40% CO-1.7-fold. It is supposed that the inhibitory effect of CO on the insect’s microsomal mixed-function oxidase and on other enzymatic systems causes this effect.     

The effect of IKI-7899, a new chitin synthesis inhibitor,on larvae ofTribolium castaneum andSpodoptera littoralis

The effect of IKI-7899 and diflubenzuron on larval development and emergence ofTribolium castaneum and ofSpodoptera littoralis was determined. The LC₅₀ of IKI-7899 at adult emergence ofT. castaneum larvae fed the compound in their diet and the ED₅₀ of S.littoralis larvae treated topically were approximately one-sixth those of diflubenzuron.     

Biological activity of the essential oil from the leaves of Piper sarmentosum Roxb. (Piperaceae) and its chemical constituents on Brontispa longissima (Gestro) (Coleoptera: Hispidae)

The results showed that the essential oil from Piper sarmentosum has strong antifeedant and toxicity effects on Brontispa longissima. The best antifeedant and contact toxicity effects were observed in the 1st-2nd instar larvae. The essential oil also displayed a notable fumigation effect on the eggs and pupae of B. longissima. It took the control-treated insects 43.34 d to complete one generation, while the insects treated with 2000 mg/L essential oil needed 73.58 d. The essential oil was analyzed by gas chromatography/mass spectrometry and 41 components were identified. Myristicin (65.22%) and trans-caryophyllene (13.89%) were the major components. Myristicin exhibited strong antifeedant and contact toxicity effects on both the 3rd instar larvae and the imagoes of B. longissima, when it showed a significant fumigation effect on the eggs and pupae of B. longissima. Another P. sarmentosum essential oil and myristicin all showed a strong inhibiting effect on the growth and development of B. longissima along with the activity of AChE, CarE, GSTs and Na⁺, K⁺-ATPase in B. longissima larvae.     

Properties of Tribolium gut chitin synthetase

An insect chitin synthetase (CS) is readily assayed using the microsomal fraction (～0.5 mg protein) from an homogenate of Tribolium castaneum larvae. This enzyme preparation is incubated at 22°C with uridine 5′-diphospho-N-acetyl[³H]glucosamine in 355 μl of 25 mM Tris-HCl buffer containing 10 mM MgCl₂, 17 mM N-acetylglucosamine, and 1 mM dithiothreitol. Other divalent cations and amino sugars are less effective activators or are inhibitory. T. castaneum CS is strongly inhibited by polyoxin D and uridine 5′-diphosphate. These activation and inhibition properties of Tribolium castaneum gut CS are similar to those of fungal CS. The polymerization product formed by the Tribolium enzyme is stable in alkali but hydrolyzed by chitinase. Enzymes of Tribolium confusum, Tribolium brevicornis, Tenebrio molitor, and Galleria mellonella are also active under the same conditions. These enzymes are from the gut and probably from the peritrophic membrane. Integumental CS activity is not detected under the indicated assay conditions.     

Seed coat texture,host species and time of application affect the efficacy of essential oils applied for the control of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) in stored pulses

The effects of the texture of seed coats of three pulse cultivars, of which two, TVu12349 (wrinkled cowpea) and Borno brown (rough cowpea) belonged to Vigna unguiculata, and one, Bunmonu (smooth bambara groundnut) belonged to Vigna subterranea, as well as pre-and post-oviposition application on the efficacy of the essential oils of clove (Syzgium aromaticum), West African black pepper (WABP) (Piper guineense) and ginger (Zingiber officinale), against oviposition and development of Callosobruchus maculatus, were investigated under prevailing storage conditions (32-35°C and 40-50% RH) and 24 h darkness in Maiduguri, Nigeria. Seed coat texture influenced the bioactivity of the essential oils, especially clove oil, against oviposition and the proportion of C. maculatus adults that emerged significantly more than host species: the mean numbers of eggs laid on the smooth-seeded Bunmonu, the rough-seeded Borno brown and the wrinkled TVu12349 were 16.9, 16.7 and 24.2%, respectively; adult emergence was 31.1% in the wrinkled TVu12349, 45.3% in the rough-seeded Borno brownand 10.2% in the smooth-seeded Bunmonu. The smooth-seeded Bunmonu reduced oviposition in seeds treated with clove oil by 91.4% and 98.4% relative to the mean number of eggs laid in the rough-seeded and the wrinkled Tvu12349, respectively; comparable figures of oviposition reduction by Bunmonu in untreated seeds were 4.8 and 15.9% relative to the mean number of eggs laid in Borno brown and Tvu12349, respectively. Both pre-and post-oviposition application of the essential oils significantly suppressed oviposition and/or adult emergence. In the pre-oviposition application, treatment of bambaranut seeds with clove, WABP and ginger oils at the rate of 1 mg/5 g seed reduced the mean number of eggs laid by C. maculatus by 70.7, 98.7 and 86.2%, respectively, relative to the number of eggs laid in untreated seeds. Post-oviposition treatments were, however, more effective on average, than pre-oviposition treatments in reducing the proportion of C. maculatus adults that emerged. In the post-oviposition application, no adult C. maculatus emerged in bambaranut seeds treated with clove oil at the rate of 0.5 or 1 mg/5 g seed.     

Contact and fumigant toxicity of plant essential oils and efficacy of spray formulations containing the oils against B‐ and Q‐biotypes of Bemisia tabaci

BACKGROUND: The contact + fumigant toxicity of 92 plant essential oils and control efficacy of 18 experimental spray formulations containing nine selected essential oils (0.5 and 0.1% sprays) and six commercial insecticides to females from B‐ and Q‐biotypes of Bemisia tabaci were evaluated using vapour‐phase mortality and spray bioassays. RESULTS: Garlic and oregano (LC₅₀, 0.15 mL cm^?3) were the most toxic oils against B‐ and Q‐biotype females. Strong fumigant toxicity to both biotype females was also obtained from catnip, cinnamon bark, clove bud, clove leaf, davana, savory and vetiver Haiti oils (LC₅₀, 0.17–0.48 mL cm^?3). The 0.5% sprays of these oils (except for thyme red oil) resulted in 90–100% mortality against both biotype females. Only garlic applied as 0.1% spray provided 100% mortality. Spinosad 100 g L^?1 suspension concentrate (SC) treatment resulted in 92 and 95% mortality against both biotype females, whereas acetamiprid 80 g L^?1 wettable powder (WP), imidacloprid 80 g L^?1 SC, thiamethoxam 100 g L^?1 water‐dispersible granule (WDG) and pyridaben 200 g L^?1 WP treatments resulted in 89–100% mortality against B‐biotype females only. CONCLUSION: In the light of global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment, the essential oils described, particularly garlic, cinnamon bark and vetiver Haiti, merit further study as potential insecticides for the control of B. tabaci populations as fumigants with contact action. Copyright © 2011 Society of Chemical Industry     

Synthetic pyrethroids: Toxicity and synergism on dietary exposure of Tribolium castaneum (Herbst) larvae

The potency of six dietary pyrethroids, as toxicants and inhibitors of weight gain in first- and fourth-instar Tribolium castaneum (Herbst) larvae, decreased in the order of cis-cypermethrin and deltamethrin > trans-cypermethrin and cis-permethrin > fenvalerate and trans-permethrin. Dosages that reduced larval weight also delayed pupation and emergence, probably due to their antifeeding activity. Three oxidase inhibitors (piperonyl butoxide, O, O-diethyl O-phenyl phosphorothioate, and O-isobutyl O-prop-2-ynyl phenylphosphonate), at a dietary concentration of 100 mg kg^?1, had little or no effect on the toxicity of trans-permethrin, but strongly synergised the toxicity of cis-cypermethrin by about 3-, 3- and 10-fold, respectively. Piperonyl butoxide also synergised the toxicity of cis-permethrin, trans-cypermethrin and deltamethrin, but not that of fenvalerate. On the other hand, an esterase inhibitor, profenofos, did not enhance the potency of any of the α-cyano-3-phenoxybenzyl pyrethroids. Oxidases appear to be more important than esterases in pyrethroid detoxification by T. castaneum larvae.     

Dose-response effects of clove oil from Syzygium aromaticum on the root-knot nematode Meloidogyne incognita

BACKGROUND: Clove oil, derived from the plant Syzygium aromaticum (L.) Merr. & Perry, is active against various organisms, and was prepared in a soy lecithin/detergent formulation to determine concentrations active against the root-knot nematode Meloidogyne incognita (Kofoid and White) Chitwood. RESULTS: In microwell assays, the mean effective clove oil concentration that reduced egg hatch by 50% (EC(50)) was 0.097% (v/v) clove oil; the EC(50) for second-stage juvenile (J2) viability was 0.145% clove oil (compared with carrier control treatments). Volatiles from 5.0% clove oil reduced nematode egg hatch in water by 30%, and decreased viability of hatched J2 by as much as 100%. Reductions were not as large with nematodes in carrier. In soil trials with J2 recovered from Baermann funnels, the EC(50) = 0.192% clove oil (compared with water controls). CONCLUSION: The results demonstrated that the tested formulation is active against M. incognita eggs and J2, that the EC(50) values for J2 in the microwell studies and the soil recovery tests were similar to each other and that direct contact with the clove oil is needed for optimal management results with this natural product.     

Malathion resistance of stored-product insects in Israel

A study was conducted to determine the extent of resistance to malathion in field populations of insects collected from nine granaries located in different regions of Israel. The results showed that the maximum resistance factor calcuated from the LC_so ^s of the different insect species tested was:Tribolium castaneum (Herbst), x 538.0;Oryzaephilus surinamensis (L.), x 8.0;Sitophilus oryzae (L.), x 1.2; andRhyzopertha dominica (F.), x 9.0. There were significant differences between the resistance level among strains collected from different locations in Israel. By using triphenyl phosphate (TPP), an inhibitor of carboxyesterase, it was shown that, in the case ofT. castaneum andR. dominica, the resistance is a malathion-specific type and that in the case ofO. surinamensis it is partially non-specific to malathion. The significance of these findings in selecting new insecticides to replace malathion as a grain protectant was considered.     

Inhibition of insect pest α-amylases by little and finger millet inhibitors

The inhibitory effect of three proteinaceous inhibitors isolated from little and finger millet was examined on gut α-amylases for four stored grain and four phytophagous insect-pests. Additionally, using native PAGE, several α-amylases isozymes were observed in all insect-pests studied. Furthermore, thermostabilities and the pH optimum for insect-pests α-amylases, which varied from acidic to alkaline, were also determined. On the other hand, proteinaceous inhibitors from little millet seeds Panicum sumatrense (LMCO3) and from finger millet (FMCO11 and FMCO13) inhibited insect-pests α-amylases with different proportions. The highest inhibition percent was recorded for LMCO3 and FMCO13 against Callosobruchus chinensis α-amylase, where the inhibition percent was approximately 70 and 50%, respectively. Furthermore, millet α-amylase inhibitors also reduced significantly digestive α-amylolytic activities of Acaea janata, C. cephalonica, Sitophilus oryzae, and Tribolium castaneum, indicating that these α-amylase inhibitors could be used toward crop insect-pests.     

Herbicidal action of clove oil on cucumber seedlings

The herbicidal action of clove oil on cucumber seedlings was characterized under light and dark conditions. Paraquat showed herbicidal activity only under the light condition, whereas the clove oil displayed herbicidal activity in both the light and the dark condition. Specifically, wilting and water content reduction progressed rapidly under both the light and the dark condition 1 h after the clove oil treatment, whereas the paraquat damage occurred only under the light condition 5 h after treatment. The malondialdehyde concentration increased more with the clove oil treatment than with the paraquat treatment under the light and dark conditions. The superoxide dismutase (SOD) activity was stimulated, but the catalase activity decreased in the clove oil treatment. In contrast, both the SOD and catalase activity decreased in the paraquat treatment. These results suggest that clove oil exerts herbicidal effects through a mechanism that is different from that of paraquat.     

The effects of low oxygen tensions on three stored-product insect pests

The relationship between different oxygen tensions and exposure times producing 95% mortality, and loss in weight of three stored-product insects at 54% R.H. and 26°C, was determined.Ephestia cautella (Wlk.) pupae andTribolium castaneum (Herbst) adults reacted in a similar pattern: the lower the oxygen concentration, the shorter the exposure time needed to produce 95% mortality, and the higher the rate of loss in weight. The response ofSitophilus oryzae (L.) adults was different: there was greater sensitivity at 1% oxygen than at the lower or higher levels of oxygen tested. A relationship was demonstrated between low oxygen tensions (0–5%) and the relative humidity of the environment for producing a lethal atmosphere forE. cautella pupae andT. castaneum adults.     

Bioactivity against Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) of Cymbopogon citratus and Eucalyptus citriodora essential oils grown in Colombia

BACKGROUND: Essential oils isolated from Cymbopogon citratus (DC) Stapf. and Eucalyptus citriodora Hook grown in Colombia were analysed by gas chromatography–mass spectrometry (GC‐MS) and tested for repellent activity and contact toxicity against Tribolium castaneum (Herbst.) (Coleoptera: Tenebrionidae). RESULTS: The main components of C. citratus oil were geranial (34.4%), neral (28.4%) and geraniol (11.5%), whereas those of E. citriodora were citronellal (40%), isopulegol (14.6%) and citronellol (13%). The mean repellent doses after 4 h exposure were 0.021 and 0.084 mL L^?1 for C. citratus and E. citriodora oils respectively—values lower than that observed for the commercial product IR3535 (0.686 mL L^?1). CONCLUSION: These studies showed the composition and repellent activity of essential oils of C. citratus and E. citriodora, suggesting that these are potential candidates as insect repellents. Copyright © 2010 Society of Chemical Industry