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1.
The residual efficacy of diatomaceous earth alone and in combination with Beauveria bassiana (Balsamo) Vuillemin or a neonicotinoid insecticide thiamethoxam against Rhyzopertha dominica (Coleoptera: Bostrychidae) was studied under laboratory conditions. The mortality of adult R. dominica was decreased over the 9?months of storage period and the combined application of the test materials enhanced the mortality rates compared with alone treatments. The greatest mortality was observed in the combination of DE with thiamethoxam. Progeny suppression was decreased with the extended storage period. The maximum rate of mycosis and sporulation in the cadavers of R. dominica was observed where B. bassiana was applied alone at the lowest-dose rate. The results of this study indicate that all three control measures may provide safety for an extended period of time against R. dominica.  相似文献   

2.
Defined populations of American (Periplaneta americana), German (Blattella germanica), and Oriental (Blatta orientalis) cockroaches, and silverfish (Lepisma saccharina) were observed after exposure to deposits (25 g/m2) of a new 1,1,1–trimethyl-N-trimethylsilane-modified, highly hydrophobic diatomaceous earth (DE) formulation by using a computer-aided device measuring motility, circadian rhythm, and mortality under defined environmental and climatic field-simulating and exposure-enforced conditions. In a humid climate (85% relative humidity) with water and food offered ad libitum, complete population eradication could be achieved on the sixth day against B. germanica, on the eighth day against P. americana, and on the ninth day against L. saccharina, respectively. No population eradication occurred within 10 days of exposure when testing B. orientalis, showing a mean survival rate of 29.4 ± 6.7 % of the populations. When comparing the species-specific mortality rates with the results obtained from corresponding reference control groups, significantly higher mortality rates could be observed in B. germanica (F = 66; df = 52; P < 0.00001), P. americana (F = 344; df =66; P < 0.00001), L. saccharina (F = 253; df = 24; P < 0.00001), and B. orientalis (F = 422; df = 11; P < 0.00001). Overall, the efficacy of the hydrophobised DE examined ranked as follows: B. germanica > P. americana (F = 51; df = 24; P < 0.00001) > L. saccharina (F = 43; df = 24; P < 0.00001) >> B. orientalis (F = 9; df = 15; P < 0.000001). DE exposure resulted in complete disruption of the circadian activity in B. germanica and P. americana, but not when tested against B. orientalis, where the species-specific circadian motility peak was still preserved at lower levels after 10 days of exposure. In contrast to the cockroach species examined, no specific circadian rhythm could be measured in the L. saccharina control and treatment groups. Results indicate that hydrophobised DE originating from freshwater diatoms modified with 1,1,1-trimethyl-N-trimethylsilane can be successfully used for the control of infestations with German and American cockroaches as well as silverfish, but not against Oriental cockroaches. It is concluded that species-specific morphological, physiological and behavioural characteristics of insects influencing DE efficacy as well as the toxicological risk of modified DE to humans deserve further investigation.  相似文献   

3.
Agrobacterium tumefaciens-mediated transformation (AMT) was used in order to create fluorescent conidia of Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales). From the fungal transformants, one Enhanced Green Fluorescent Protein B. bassiana strain indicated stability (maintained the GFP characteristics) in fluorescent signal, while its pathogenicity did not differ significantly from the wild B. bassiana type. After exposure on wheat treated with the transformed conidia, fluorescence was evident on all body parts but especially on metasternon of adults of Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) and on elytra in of Sitophilus oryzae (L.) (Coleoptera: Curculionidae). No significant differences were noted in fluorescence levels in the case of T. confusum between the transformed and the wild strain. However, the addition of diatomaceous earth (DE) increased attachment, especially at increased intervals after exposure. For S. oryzae, fluorescence of the transformed strain was decreased with the increased post-exposure time, but the simultaneous presence of DE increased fluorescence. The results of this study demonstrate that fluorescent conidia of B. bassiana can be utilized as a tool for the evaluation of parameters that affect the attachment of entomopathogenic fungi in insects?? cuticle.  相似文献   

4.
5.
Diatomaceous earth has been demonstrated in Australia, Germany, and the USA to protect stored products from infestation by insect pests. However, application of diatomaceous earth has rarely been used in Asian countries for the protection of stored grain from insect damage. These facts and the paucity of existing data from the tropics prompted the present study of storage with diatomaceous earth. We exposed rice treated with the diatomaceous earth product Fossil Shield® to infestation by Tribolium castaneum Herbst. During the dry season, when tests were conducted, the mean temperature was 29?±?2?°C and relative humidity was 80?±?3?%. The population of T. castaneum in rice was significantly reduced after treatment with Fossil Shield®. Diatomaceous earth at 1?g and 2?g per kilogram rice reduced population growth of T. castaneum to a coefficient of 0.27, and 0.02 respectively after 42 days. Fossil Shield® at 0.5?g per kilogram rice increased the mortality of T. castaneum, but did not stop population growth.  相似文献   

6.
The insecticidal efficacy of five diatomaceous earth (DE) formulations, Protect-It®, SilicoSec®, Insecto®, Perma-Guard? D-10 and Dryacide® was evaluated against adult Tribolium castaneum Herbst, the red flour beetle, on three oilseeds: safflower, sunflower and sesame. The DE formulations were applied at three rates: 0.5, 1 and 1.5 g/kg. The experiment was carried out at 26°C and 55 (±5)% RH in the dark. The mortality of T. castaneum adults was measured after 3, 7, 14 and 21 days exposure. After the 21-day mortality count, all surviving insects were removed and the samples retained under the same conditions for a further 45 days to assess progeny production (F1). Significant differences were recorded among the three oilseed types as well as between the DE formulations tested. After 21 days exposure, even at the lowest treatment rate, adult mortality was high (>90%) in safflower for all DE formulations. In contrast adult mortality was significantly lower in the case of sesame. Increased application rates improved the efficacy of DEs in sunflower and sesame. Even at the lowest rate the complete suppression in progeny production was achieved on treated safflower. The greatest number of progeny was recorded for treated sunflower seeds. Protect-It® and Dryacide® were the most efficient DE formulations against T. castaneum.  相似文献   

7.
The results of the clinical assessment of a multiherbal indigenous formulation on 22 patients with bleeding piles are reported.  相似文献   

8.
ABSTRACT

Two formulations of wood preservative one containing water-dispersible copper naphthenate (CuN) alone and in combination with sodium fluoride (NaF) were used to treat southern pine sapwood blocks to determine the effect of the addition of sodium fluoride in the QNS on the protection against wood decay fungi using laboratory soil block tests following AWPA (American Wood protection Association) standard E10-16 [American Wood Protection Association AWPA-E10. (2016 American Wood Protection Association. (2016) Standard E10-16 Laboratory Method for Evaluating the Decay Resistance of Wood-Based Materials Against Pure Basidiomycete Cultures: Soil/Block Test. [Google Scholar]) Laboratory Method for Evaluating the Decay Resistance of Wood-based Materials Against Pure Basidiomycete Cultures: Soil/Block Test]. The standard consists in exposing treated blocks to pure monoculture of white rot (Irpex lacteus (FP-105915) and Trametes versicolor (R-105)) and brown rot fungi (Gloeophyllum trabeum (Madison 617) and Postia placenta (Madison 698) during a specific period. The weight loss (WL) in percentage of treated blocks was used as an indicator of the biological performance of treated blocks against basidiomycetes at specific retentions. Minimum WL was obtained with blocks treated with the formulation containing mixture of QNS and sodium fluoride with the retention of 0.29?kg/m3 Cu and 0.51?kg/m3 of fluorine in treated blocks. A copper retention of 1.65?kg/m3 from blocks treated with formulations containing only QNS was needed to obtain similar WL to blocks containing blocks Cu++ and F? (fluorine). The lower Cu retention is attributed to a combination of the presence of the fluorine with some toxic activities against bacteria and decay and the interaction of anions fluorine and ionic Cu (II) in the aqueous treating solutions to form more soluble biological toxic hydrate of copper fluoride ((H2O Cu (II) F2) in treated blocks compared to copper complexes less biological available in water-dispersible CuN-treated bocks.  相似文献   

9.
Efficacy of the insecticides spinosad and methoprene, applied alone or in combination to wheat, was evaluated against six stored-product insect species, Rhyzopertha dominica, Sitophilus oryzae, S. granarius, Cryptolestes ferrugineus, Oryzaephilus surinamensis, and Liposcelis bostrychophila. The concentrations of the insecticides were 0.1 and 0.5 ppm for spinosad and 1 and 5 ppm for methoprene. Parental mortality of R. dominica was 100% on wheat treated with either rate of spinosad, with no progeny production in any combination treatment. Parental mortality of S. oryzae did not exceed 62%, and progeny production was not reduced by any insecticide treatment. All S. granarius adults exposed on wheat treated with spinosad alone at 0.5 ppm were killed, but parental mortality was reduced when methoprene was added. Progeny production was reduced in treatments containing spinosad. Mortality of adult C. ferrugineus was 97% or greater in treatments containing spinosad, but adult mortality of O. surinamensis and L. bostrychophila was not reduced by insecticide treatments. The specific combinations of spinosad and methoprene evaluated in our study would have no benefit over spinosad used alone for control of any of the six species tested.  相似文献   

10.
Recently, Apolygus lucorum (Hemiptera: Miridae) has become an important insect pest of Bt cotton and fruit trees in China. At present, the application of chemical insecticides is the main control option for this pest. We investigated the lethal effect of seven neonicotinoid insecticides on A. lucorum adults, including six commercialized neonicotinoids and a novel one, cycloxaprid, which is developed in China. In addition, we assessed the sublethal physiological (longevity, fecundity) and behavioral (pre-oviposition and oviposition periods) effects of LD10 (low lethal dose) and LD40 (moderate lethal dose) of cycloxaprid on the mirid bug. Lethal effect of the insecticides was determined using a topical exposure method; contact toxicity against the adults was ranked as follows: cycloxaprid, nitenpyram > clothianidin > acetamiprid, imidacloprid > thiamethoxam > dinotefuran. Among these insecticides, the toxicity of cycloxaprid against the adults was the highest; its LD50 value was 2.54 ng a.i. (active ingredient)/adult. Both LD10 (0.74 ng a.i./adult) and LD40 (1.98 ng a.i./adult) of cycloxaprid induced sublethal effects in the adults; we observed a reduced longevity in males and the LD40 also shortened the longevity of females. In addition, the LD40 prolonged the pre-oviposition period and shortened the oviposition period of females, and it decreased their fecundity. The hatching rate of eggs laid by the females exposed to LD10 and LD40 greatly decreased (two-fold lower when exposed to LD40). Our results demonstrate that cycloxaprid is among the best candidate insecticides for controlling A. lucorum, and it showed significant lethal and sublethal effects on this mirid bug.  相似文献   

11.
Margosan-0, a commercial preparation of neem seed kernel extract was tested for its effects as toxicant, deterrent and sterilant against the bean aphidAphis fabae and compared with the German product Neem-Azal S. Second and 4th nymphal instars ofA. fabae, placed on bean plants treated with different concentrations of Margosan-0 or Neem-Azal S, were adversely affected and very high percentage of mortality occurred after 96 hours. In a choice test, higher numbers of adults settled and larviposited on plants treated with Margosan-0 in comparison to the control. Neem-Azal S treated plants showed high deterrence to the adults at high concentrations. The deterrent effect was reflected in a reduced larviposition. Plants treated with different concentrations of either Neem-Azal S or Margosan-0 significantly affected the longevity and fecundity ofA. fabae. The efficacy of Neem-Azal S is more pronounced than that of Margosan-0.  相似文献   

12.
The furano-lignan pinoresinol was toxic to fourth-instar larvae of the milkweed bug Oncopeltus fasciatus and of the haematophagous insect Rhodnius prolixus, a vector of Chagas disease. At lower doses, it also exerted antifeedant activity and dose-dependent antimoulting activity on both insects.  相似文献   

13.
Chive gnat, Bradysia odoriphaga Yang & Zhang (Diptera: Sciaridae), is the most serious pest of Chinese chive, Allium tuberosum. The present study aimed at determining the biocontrol potential of different indigenous entomopathogenic nematode (EPN) isolates for the management of chive gnat in China. The virulence of 145 EPN isolates belonging to 13 species against B. odoriphaga was evaluated in the laboratory, and then the most promising isolates (Steinernema ceratophorum HQA-87; S. hebeiense JY-82; S. feltiae JY-90, JY-17; S. litorale HXY-68; Heterorhabditis indica ZZ-68; H. bacteriophora NY-63, HQ-94; and H. megidis LFS-10) were selected for further experiments. The mortality of fourth instar B. odoriphaga was significantly affected by nematode isolates and concentrations of infective juveniles (IJ). Third and fourth instars of B. odoriphaga were generally more susceptible to the nematodes than first and second instars and pupae. Pot experiments showed no differences in B. odoriphaga population reduction at 50 and 75 IJ/cm2 of different isolates; the tested isolates caused a 78–94 % reduction of the chive gnat population at an application rate of 75 IJ/cm2. In a field experiment, S. feltiae JY-90 generated the strongest pest suppression 14 days after EPN application, whereas after 28 days pest densities in the plots treated with S. feltiae JY-17 and S. hebeiense JY-82 were similar to those in plots treated with phoxim and yielded significant reductions of the B. odoriphaga populations. Our findings indicate that EPN may have good potential for use in the integrated management of B. odoriphaga populations in Chinese chive.  相似文献   

14.
The invasive Halyomorpha halys was accidentally introduced into Switzerland around 2004 and has recently established in the neighbouring countries of France and Italy. To better understand the population dynamics of this pest in Europe, the phenology, reproductive biology and temperature requirements of Swiss H. halys populations were investigated. Overwintered adults became active in April, but peak oviposition was not observed before early July. Individual females laid on average 79 eggs (maximum of 160). The oviposition period lasted from mid-June to end of September. Eggs laid in August and September did not result in offspring due to the low temperatures in autumn. Under natural fluctuating temperatures, development from egg to adult lasted between 60 and 131 days. The first new generation of adults did not occur before mid-August when the photoperiod was already below 15 h, which likely initiated diapause and suppressed the reproductive activity of new generation adults. Under controlled conditions of 20, 25 and 30 °C, Swiss H. halys populations developed within 75.8, 42.3 and 33.2 days from egg to adult, respectively. No development was possible at or below 15 and at or above 35 °C. The number of degree days required for completion of development from egg to adult was 588.24 DD. Under semi-natural conditions, total mortality of Swiss H. halys populations was 86.7 % with a net reproductive rate of 5.69, indicating growing populations. In Switzerland, H. halys is univoltine, but if it continues to spread into the Mediterranean area two generations per year could be expected.  相似文献   

15.
In the present work, the insecticidal effect of two pirimiphos-methyl formulations [emulsifiable concentrate (EC) and capsule suspension (CS)] as surface treatment on concrete, plywood, galvanized metal, plastic, and ceramic tile was evaluated in laboratory bioassays against Sitophilus granarius (L.), Rhyzopertha dominica (F.), and Tribolium confusum Jacquelin du Val. Pirimiphos-methyl was applied at two-dose-rates, 0.01 and 0.1 mg/cm2, and insect mortality was assessed after 1, 2, 3, 4, 5, 6, and 7 days of exposure. After the final mortality count, alive individuals were transferred to untreated dishes, and delayed mortality was evaluated after an additional period of 7 days. In another series of laboratory bioassays, the residual efficacy of these two pirimiphos-methyl formulations on concrete was evaluated against S. granarius, R. dominica, and T. confusum. Pirimiphos-methyl was applied at two-dose-rates, 0.01 and 0.1 mg/cm2, on concrete dishes which were either kept in continuous darkness or exposed to light. A bioassay was initiated at the day of storage and every 4 weeks for 4 consecutive months (5 bioassays in total). Mortality of the exposed adult beetles was measured after 3 and 7 days of exposure. Both formulations were highly effective, with S. granarius being the most susceptible species. In general, mortality of the exposed beetles was not significantly affected by the surface type, with the exception of the significantly lower mortality counts of S. granarius adults on ceramic tile. CS appeared to be much more persistent on concrete than EC for all three species tested. Moreover, CS was not affected by light. In contrast, in some of the combinations tested, EC performance was poor in dishes that were exposed to light, in comparison with dishes that were in continuous darkness. We conclude that the surface type does not significantly and consistently affect S. granarius, R. dominica, and T. confusum mortality after surface application of the two pirimiphos-methyl formulations tested. Furthermore, CS can provide long-term protection when applied on concrete surfaces.  相似文献   

16.
随着草本花卉在园林苗圃连年的大量种植,温室内蛞蝓大量发生,危害日益严重。结合蛞蝓的生活习性及其在草本花卉温室内的危害特点,采取一系列综合防治措施,达到防患于未然、控制其数量、减少其危害的防治效果。  相似文献   

17.
Since its introduction from Asia, the brown marmorated stink bug, Halyomorpha halys (Stål), has become a pest of many agricultural crops in the USA. Insect predators utilize H. halys as prey; however, the chemical cues used by them in prey location are largely unknown. Here, we hypothesized that tridecane, an H. halys-associated volatile, acts as a kairomone for the predaceous minute pirate bug, Orius insidiosus (Say). We conducted laboratory, greenhouse, and field experiments to: (1) assess the attraction of adult O. insidiosus to H. halys-damaged bean pods and tridecane in cage studies, and its effect on egg predation; (2) video record the behavioral response of O. insidiosus males and females to tridecane in a four-arm olfactometer; and (3) test whether Orius spp. are attracted to tridecane-baited sticky traps in peach, blueberry, and sunflower fields, and its effect on egg predation. In the greenhouse, O. insidiosus was attracted to H. halys-damaged pods and artificial plants baited with tridecane in the presence of prey (sentinel eggs); however, this attraction rarely led to increased egg predation. Although both O. insidiosus males and females spent more time in the arm of the olfactometer with tridecane, males were more responsive at a lower concentration than females. Similarly, Orius spp. were more attracted to tridecane-baited than unbaited traps in the field; however, there was no effect on egg predation. Altogether, while O. insidiosus is attracted to tridecane, this attraction did not always lead to higher predation, suggesting that this kairomone likely acts as an arrestant.  相似文献   

18.
平凉市果树蚧壳虫主要有7种,优势种为苹果球蚧、朝鲜球蚧、梨圆蚧和桑白蚧。调查明确了蚧壳虫分布范围和危害概况,初步分析了发生消长因素,并提出了防治建议。  相似文献   

19.
Phytophthora ramorum, cause of sudden oak death, has been distributed widely across the United States in horticultural situations, but is not established in forests outside of California and Oregon. Here, it has triggered widespread concern and, especially in Oregon, an intensive disease management programme. Now, we provide the first systematic evaluation of the efficacy of that effort. This paper evaluates four measures of the efficacy of Sudden Oak Death (SOD) local eradication treatments: inoculum availability; inoculum from tree species other than tanoak; disease spread from treated areas; and cumulative infested area with and without treatment. We conclude that local treatments demonstrably reduce local inoculum levels. Eradication of SOD from infested sites is difficult but not impossible. The disease usually does not persist after cutting infected trees but spread on the landscape continues because the pathogen may be present on undetected new infections for a year or two before whole tree symptoms are visible. This limits early detection and coupled with delays in completing eradication treatments, prolongs the chances for long‐distance aerial dispersal.  相似文献   

20.
室内测定了3% 高效氯氰菊酯微囊悬浮剂、1.2% 烟碱· 苦参碱乳油、25% 灭幼脲可湿性粉剂 和 2% 阿维· 苏云菌可湿性粉剂4 种药剂对海榄雌瘤斑螟(Ptyomaxia sp.)1~2 龄幼虫的防治效果。结果 表明,在5 000 倍 ~100 000 倍稀释药剂测定范围内,不同药剂处理之间海榄雌瘤斑螟幼虫死亡百分率均 值差异极显著,防治效果为高效氯氰菊酯>烟碱 · 苦参碱>灭幼脲>阿维 · 苏云菌。喷药防治后第 10 天, 高效氯氰菊酯 5 000 倍液、10 000 倍液、50 000 倍液以及灭幼脲 5 000 倍液的海榄雌瘤斑螟幼虫死亡百分 率为 91.67%~93.33%,烟碱 · 苦参碱 5 000 倍液为 87.50%。3 月下旬至 4 月上旬,高效氯氰菊酯、灭幼脲 和烟碱 · 苦参碱在红树林中防控海榄雌瘤斑螟危害具有应用前景。  相似文献   

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