Susceptibility of selected stored product insects to a combination treatment of pyriproxyfen and novaluron

There are many published studies of either insect growth regulators (IGR) or chitinase inhibitors applied directly to larvae of stored product insects or incorporated into their diets, but few studies evaluating efficacy of IGRs or chitinase inhibitors applied alone or in combination with a surface for residual control. Tests were conducted to evaluate susceptibility of Tribolium castaneum (Herbst), the red flour beetle, Trogoderma variabile (Ballion), the warehouse beetle, and Dermestes maculatus (DeGeer), the hide beetle, to Tekko^® Pro which contained the IGR pyriproxyfen and the chitinase inhibitor novaluron as active ingredients. Efficacy was assessed by adult emergence of exposed immatures, an index based on development of those exposed immatures, and progeny production of exposed adults. Concrete arenas were treated with the label rate of the insecticide applied to a surface, and bioassays were conducted at 0–16 weeks post-treatment. No exposed T. castaneum eggs or larvae reached the adult stage and index values for exposed eggs and larvae remained near the minimum. Adult emergence of T. variable from eggs or larvae did not exceed 25% for the first 8 weeks of the test, but at the end of the test at 16 weeks adult emergence was 44 and 71%, respectively, for eggs and larvae. No eggs or larvae of D. maculatus emerged as adults, but excessive cannibalization in untreated controls occurred throughout the test. Results show that Tekko^® Pro will give residual control of T. castaneum and T. variabile, and could replace older conventional neurotoxic insecticides for management of stored product insects.     

Performance of pre-commercial release formulations of spinosad against five stored-product insect species on four stored commodities

Two liquid and one dry pre-commercial release spinosad formulations were evaluated at the labeled rate of 1?ppm against five stored-grain insect species on wheat, short-grain rice, long-grain rice, and maize. Except on maize, efficacy of spinosad was compared with a currently registered grain protectant, chlorpyrifos-methyl (3?ppm) plus deltamethrin (0.5?ppm). The 7- and 14-day mortalities of the lesser grain borer, Rhyzopertha dominica, were 99.0-100.0% on spinosad and chlorpyrifos-methyl plus deltamethrin-treated wheat, short-grain rice, and long-grain rice. Adult progeny of R. dominica after 42?days on these commodities decreased by 99.7-100.0% relative to progeny production on untreated wheat. Mortality and reduction in adult progeny of the rice weevil, Sitophilus oryzae, on the three commodities, and that of the maize weevil, Sitophilus zeamais, on maize and the red flour beetle, Tribolium castaneum, on wheat were 100.0% only with chlorpyrifos-methyl plus deltamethrin. The liquid spinosad formulations were most effective against the Indianmeal moth, Plodia interpunctella, on maize and wheat. Except for R. dominica, the effectiveness of spinosad on the other species varied with the formulation, exposure time, and commodity. Chlorpyrifos-methyl plus deltamethrin was effective against insect species on the commodities tested.     

几种杀白蚁药剂或混配剂对黑翅土白蚁的室内毒力测定

对 1 5种杀白蚁药剂或混配剂对黑翅土白蚁 Odontotermes formosanus(Shiraki)室内直接毒杀速度和传递毒杀效率的测定结果表明 :毒死蜱、锐劲特、安绿宝、溴氰菊酯、辛硫·灭扫利等 5种药剂对黑翅土白蚁的毒杀效果均接近或优于常用的氯丹 ;同时 ,毒死蜱、锐劲特等药剂与植物性杀虫剂混配 ,其毒杀效果与毒死蜱等单独使用效果一致或略高 ;但植物性杀虫剂单独使用 ,其毒杀效果却低于氯丹     

巨无敌兼治园林蚜虫、螨类药效试验

多种药剂的室内、室外和生产防治试验表明，37％巨无敌乳油是一种兼治蚜虫、螨类的安全、经济、高效、低毒农药。另外，对蚜虫、螨类的防治时机、药剂的喷洒浓度进行了研究。     

A new monomeric α-amylase inhibitor from the tetraploid emmer wheat is mostly active against stored product pests

Journal of Pest Science - The tetraploid domesticated emmer wheat, Triticum turgidum L. subsp. dicoccon, expresses α-amylase protein inhibitors of varying sizes and assemblies, i.e. dimers and...     

5种芳香型植物叶提取液对线虫活性影响的测定

研究测定了5种芳香型植物叶提取液杀灭线虫生物活性的效果.结果表明,不同种植物的叶提取液,对线虫杀灭活性存在明显差异.其中以桂花、广玉兰叶的水提取液对甘薯茎线虫致死效果较好,杀灭率分别为74.07%和54.75%.另外比较了不同植物叶提取液对线虫杀灭效果与作用时间的关系.     

五种杀虫剂对槟榔成蚜的室内毒力测定

槟榔蚜虫是棕榈科植物叶子、花果、苞叶上经常发生的昆虫。该研究主要通过玻片浸渍法测定了施定康、特福力、可汗、顺发宁以及30%吡丙醚·溴虫腈SC这五种杀虫剂对槟榔成蚜的毒力。结果表明这五种杀虫剂分别对槟榔蚜虫处理24h后,其作用效果按计算的LC₅₀值大小比较,其毒力效果强弱依次为:顺发宁>特福力>施定康>30%吡丙醚·溴虫腈SC>可汗;处理48h后,其作用效果按计算的LC₅₀值大小比较,其毒力效果强弱依次为:施定康>顺发宁>特福力>30%吡丙醚·溴虫腈SC>可汗。     

Seed viability of selected tree,shrub, and vine species stored in the field

Seeds from 10 species were collected, sealed in fiberglass screen pouches, and stored under hardware-cloth cages on both a forest and cleared site for up to five years. At each site, half of the pouches were placed under leaf litter and the other half were planted in mineral soil. Liquidambar styraciflua and Callicarpa americana seeds had high germination rates under all conditions. Quercus falcata, Sassafras albidum, Rhus copallina, and Vaccinium arboreum required planting in mineral soil to ensure germination. Planted Myrica cerifera and Vitis aestivalis seeds germinated well on both sites. Myrica cerifera also germinated well if placed under litter on the forest floor and Vitis aestivalis if placed under litter on the cleared site. Germination of Crataegus uniflora seeds was erratic. Most Lonicera japonica were unsound when collected. Germination rates generally decreased over time, but some Sassafras albidum, Myrica cerifera, and Vaccinium arboreum seed germinated after four years, and Rhus coppalina, Callicarpa americana, Crataegus uniflora, and Vitis aestivalis seeds germinated after five years in the field.     

CPV-Bt对湖南马尾松毛虫的药效试验

以湖南马尾松毛虫发生地采集的马尾松毛虫为试验材料,选用CPV、Bt 2种微生物复配后对其进行室内药效试验,结果表明：Bt对越冬代松毛虫前12d死亡率的影响显著,死亡率与Bt浓度呈正比,Bt浓度为6×10^7个芽孢／mL时,死亡率可达70．36％;Bt使用浓度为5×10^6芽孢／mL时,第一代松毛虫（群体饲养）处理6d平均死亡率可达70．41％,Bt使用浓度为1×10^7芽孢／mL时,平均死亡率可达75．09％;CPV对越冬代松毛虫处理12d后残留种群带毒率影响显著,带毒率与CPV浓度呈正比,当CPV浓度为2×10^5个多角体／mL时,其带毒率可达53．68％;复配药荆按其对第一代松毛虫（单虫饲养）的药效（前6d死亡率）可分为5类,其平均药效（死亡率）最高达100％,最低的仅为43．12％;CPV-Bt复配药刺防治马尾松毛虫的越冬代和第一代,若只需达到70％杀虫率和50％残留种群带毒率水平,越冬代宜选用2×10^5个多角体／mL＋6×10^7个芽孢／mL,第一代宜选用5×10^4个多角体／mL＋1×10^7个芽孢／mL。     

Repellent activity of selected essential oils against Aedes aegypti

Essential oils extracted from ten plant species were screened for repellency against Aedes aegypti mosquitoes. Three oils; Zanthoxylum piperitum, Anethum graveolens and Kaempferia galanga, exerted protection against A. aegypti, with median complete-protection times of 1, 0.5 and 0.25 h, respectively. The protection times were increased significantly by incorporating 10% vanillin. The highest potential was established from Z. piperitum oil +10% vanillin (2.5 h, range=1-2.5 h). Mixtures from pairs of the effective oils possessed slight repellency that ranged from 0-0.5 h. None of the oil combinations repelled A. aegypti for longer than their constituent oil alone. With vanillin added, however, each oil mixture provided improved protection, which was approximately equal to oil on its own. GC/MS analysis revealed that the main component of Z. piperitum fruit oil was limonene (37.99%), with minor amounts of sabinene (13.30%) and beta-myrcene (7.17%). Repellent testing of stored samples of Z. piperitum fruit oil against A. aegypti demonstrated that repellent activity of those kept at -20 degrees C or 4 degrees C was present for a period of at least 3 months. Therefore, the essential oil of Z. piperitum fruit may prove useful in the development of mosquito repellents as an effective personal protection measure against mosquito bites.     

Repellent activity of five essential oils against Culex pipiens

Essential oils extracted from the seeds of anise (Pimpinella anisum), dried fruits of eucalyptus (Eucalyptus camaldulensis), dried foliage of mint (Mentha piperita) and basil (Ocimum basilicum) and fresh foliage of laurel (Laurus nobilis) were tested for their repellency against the adult females of Culex pipiens. All essential oils showed repellency in varying degrees, eucalyptus, basil and anise being the most active.     

An investigation and comparison of the bioactivity of selected essential oils on human lice and house dust mites

The insecticidal potency of some essential oils suggests that they may find an application in the control of house dust mites, but current in vitro assays for mites do not appear to give consistent results. A simple, novel, mite chamber assay was therefore developed to carry out testing. Different species of insects are susceptible to different essential oil components, so we compared the relative acaricidal and pediculicidal activity of three essential oils: tea tree, lavender and lemon, because the activity of their constituents on lice ranges from highly active to virtually inactive. The most effective essential oil against both lice and mites was tea tree oil; lavender was the second most effective, and lemon oil the least, although it did show activity against mites, unlike lice. The assay proved simple and effective and gave reproducible results.     

Evaluation of spinetoram and spinosad for control of Prostephanus truncatus,Rhyzopertha dominica,Sitophilus oryzae,and Tribolium confusum on stored grains under laboratory tests

Spinetoram and spinosad have been evaluated against certain stored-product insect pests with success but there are no data available on the comparison of the efficacy of these two novel compounds in stored grains. Thus, laboratory bioassays were conducted to compare spinetoram and spinosad as grain protectants against Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae) adults, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) adults, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) adults, and Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) adults and larvae. Factors such as treatment (1 ppm spinetoram, 1 ppm spinosad, 0.1 ppm spinetoram + 0.9 ppm spinosad, 0.5 ppm spinetoram + 0.5 ppm spinosad, and 0.9 ppm spinetoram + 0.1 ppm spinosad), exposure interval (1, 2, 7, and 14 days), temperature (20, 25, and 30 °C), and commodity (barley, maize, rye, and wheat) were evaluated. Progeny production was assessed after 60 days of exposure. Concerning temperatures, for P. truncatus adults, after 14 days of exposure, all adults were dead in treatments except of the case of spinosad alone at 20 °C. Offspring emergence was completely suppressed in all treatments at 20 and 25 °C. For R. dominica adults, after 7 days of exposure, the overall mortality ranged from 92.8 to 100 %. After 14 days of exposure, all adults were dead in all treatments of the combined use of spinetoram and spinosad at 25 and 30 °C. Progeny production was completely suppressed in all treatments at 30 °C. For S. oryzae adults, after 7 days of exposure, all S. oryzae were died at 25 and 30 °C in all treatments except in the case of spinosad alone. Offspring emergence was very low in all treatments and temperatures except in the case of spinosad alone at 30 °C. For T. confusum adults, after 1, 2, and 7 days of exposure, the overall mortality was low in all treatments and temperatures. Concerning commodities, for R. dominica adults, after 7 and 14 days of exposure, the overall mortality was >97 %. Offspring emergence was very low in all commodities. For S. oryzae adults, after 7 and 14 days of exposure, the overall mortality was increased exceeding 91 % except in the case of spinosad alone 7 days after exposure in barley. Progeny production was high in barley and rye in all treatments. For T. confusum adults, after 7 and 14 days, the overall mortality was low in barley, rye, and wheat. No offspring emergence was recorded in all treatments and commodities. For T. confusum larvae, after 14 days of exposure mortality was further increased, but did not reach 100 % for any of the combinations tested. The results of the present study suggest that the simultaneous application of spinetoram and spinosad was generally equally effective with the use of either spinosad or spinetoram alone. Furthermore, the increase of dose of either compound resulted in the same mortality levels. Thus, no benefits were achieved when spinetoram and spinosad were used simultaneously on grains, regardless of the proportion of each ingredient. These issues should be seriously considered when control measures against stored-product insects are designed.     

The efficacy of selected biological and chemical control agents against Heterobasidion abietinum on Abies cilicica

The efficacy of 30% aqueous urea solution, borax powder and spore suspensions of Phlebiopsis gigantea and Trichoderma harzianum against establishment of artificially inoculated Heterobasidion abietinum on Abies cilicica was tested both in the field and in a simulated stump treatment experiment carried out in a growth chamber. In the field, in each of the four selected stands 20 fresh stumps per control agent were treated and 20 stumps were left as untreated controls. In two of the stands, the treatments were applied in June and in the two others in November. Stumps were sampled twice, at 6‐ and 12‐months after treatment. In the growth chamber, 10 log pieces per treatment and control were used, and sampling performed after 6‐week incubation. Results of the urea and borax treatments were consistent between the experiments; the mean efficacies were 98.8 and 99.4% in the growth chamber, and 80.2–91.3 and 89.4–90.1% in the two samplings of the field experiment, respectively. Despite the high efficacies of the P. gigantea (85.9%) and T. harzianum (97.5%) treatments in the growth chamber, efficacies of these biological control agents in the field were 47.1–49.2 and 61.3–65.5%, respectively.     

五种杀菌剂防治菩提树黑痣病试验

黑痣病[Phyllachora repens(Corda)Sacc.]是菩提树Ficus religiosa的主要病害。选用代森锰锌、多菌灵、甲基硫菌灵、咪鲜胺和等量式波尔多液5种杀菌剂测定其对菩提树黑痣病病原菌子囊孢子萌发的抑制作用,并用于大田试验。结果表明,波尔多液和代森锰锌对孢子萌发抑制效果最为显著,田间防治试验也以波尔多液和代森锰锌的防效最好。     

MA-chitosan nanogel loaded with Cuminum cyminum essential oil for efficient management of two stored product beetle pests

Natural essential oils have received increased attention as alternatives to synthetic pesticides for pest management of foodstuffs. Recently, microencapsulation and other controlled release techniques are used to increase insecticidal efficiency and persistence of essential oils with slow and controlled release. In this study, the possibility of improving the insecticidal activity of plant essential oils was investigated for effective management of two stored product beetle pests. Self-assembly technique was used to prepare nanogels of myristic acid-chitosan loaded by essential oil extracted from cumin, Cuminum cyminum L. Fumigant toxicity of C. cyminum oil and oil-loaded nanogels (OLNs) were investigated at 4, 7, 10, 13, and 16 µL/L air against the granary weevil Sitophilus granarius L. and 8, 11, 14, 17, and 20 µL/L air for confused flour beetle Tribolium confusum Jacquelin du Val. Experiments were conducted at 27 ± 1 °C and 55 ± 5 % relative humidity in continuous darkness. Insecticidal bioassay revealed that OLNs were more toxic than C. cyminum oil against tested beetle pests. The persistence of the oil and OLNs was also evaluated against two tested species. Results indicated that C. cyminum oil completely lost its insecticidal activity after 12 days, whereas at the same period, the OLNs lost about 60 % of its activity when applied against S. granarius and 15% for T. confusum. Therefore, it could be concluded that encapsulation improved the persistence of the oil.     

Methodical improvements of standard laboratory tests for determining the sideeffects of agrochemicals on predatory mites (Acari: Phytoseiidae)

In the course of the alignment of national registration procedures with general EU guidelines, changes, improvements and validation of current test guidelines are advisable. The following is intended to contribute to the improvement of the present standard laboratory test procedure with predatory mites, as described byOvermeer (1988). Changes in the design of the test arena are described and discussed. They provide an open test system, conform with the requirements of the ESCORT Guidance Document (Anonymus 1994), avoiding uncontaminated areas on the test unit, easy to handle, and enabling reproducible assessments of the impact of agrochemicals.     

8种杀菌剂对桉树枝枯病病原菌室内毒力测定

选择8种不同的杀菌剂,用菌落生长速度法对桉树枝枯病主要病原菌可可毛色二孢、拟隐孢壳菌进行了室内毒力测定。结果表明:对可可毛色二孢抑菌效果最好的是25%咪鲜胺,EC50值为0.03 mg/L,效果最差的是50%异菌脲,EC50值为11.49 mg/L;对拟隐孢壳菌抑菌效果最好的是25%咪鲜胺,EC50值0.23 mg/L,效果最差的是25%苯醚甲环唑,EC50值为6.65 mg/L。