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1.
In honeybee, Apis mellifera, colonies infested with larval and adult small hive beetles (SHB), hive material, and in particular honey, tends to ferment, probably due to SHB-associated yeasts such as the predominant Kodamaea ohmeri. Here, we test the effects of organic acids on K. ohmeri and on SHB-infested honey/pollen combs. Organic acids were applied at standard concentrations used by beekeepers to control other pests. In laboratory tests, the growth of K. ohmeri was significantly inhibited by lactic, formic and acetic acids. Treatments of SHB-infested honey/pollen combs (N = 18 colonies) with acetic acid significantly increased mortality of adult SHB and treatments with formic acid significantly reduced larval infestation. Our data suggest that treatment of honeybee colonies and storage rooms with organic acids could also help in reducing SHB damage.  相似文献   

2.
Damages caused by the larvae of Byturus tomentosus (Coleoptera: Byturidae) are a big problem of European raspberry production. Under integrated pest management conditions in Switzerland, B. tomentosus is controlled by chemical-synthetic insecticides. In organic production, no corresponding insecticides are permitted. White sticky traps (type Rebell® bianco) are used for monitoring purposes. Can glue-traps also be used for mass-trapping and damage control? In this study, the attractiveness for adult B. tomentosus of one yellow and several white glue-traps was compared by counting the trapped individuals. Trapped beneficial insects like honey bees, Coccinellidae, Syrphidae and Chrysopidae were also counted. The contamination of the traps caused by other non-target arthropods was measured by a computer-assisted method. The white sticky trap type Rebell bianco was the most attractive for B. tomentosus. The attractiveness for the beneficials was relatively low, except when too much glue was applied on the traps, then the attractiveness for honey bees increased significantly. In this study, traps, which were placed in high densities (17 traps per 100 m2), significantly decreased the damages caused by larvae by around 40%. The trapping method does not cause any residuals of pesticides on the fruits or soil. Therefore, the trapping method could be an alternative to control B. tomentosus, especially in organic production.  相似文献   

3.
Nine isolates ofBacillus thuringiensis Berliner belonging to var.kenyae, var.aizawai and var.entomocidus, were bioassayed against 1st instar larvae ofBoarmia (Ascotis) selenaria Schiffermüller and compared withB. thuringiensis var.kurstaki, HD-1-S-1980. None were found to have a higher potency than HD-1-S-1980, which is used for commercial control of young larvae of this pest in avocado plantations in Israel.  相似文献   

4.
The Egyptian cotton leafworm,Spodoptera littoralis Boisd., is the main important pest of alfalfa in Israel. Population levels of other pests usually do not reach the economic threshold. Nine chemical insecticide applications (7 spray applications and 2 granular fluorosilicate baits) were required to controlS. littoralis during the season of 1984 (in which infestation level was high) whereas only 5 applications of aBacillus thuringiensis var.entomocidus (Bte) preparation (3 sprays and 2 baits) produced the same effect. During 1983 and 1985 pest populations were moderate and only 6 chemical pesticide applications were required. A bait ofBte on wheat bran, Coax®, developed in the present study was effective in the control of large larvae (instars 4–6). Hay yields of fields treated withBte were similar to the yields of a conventionally treated field. The best control of large larvae was obtained by applying the bait preparation under the wind row during the alfalfa cutting.  相似文献   

5.
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   

6.
Persistence of neem-based products against sweetpotato whitefly Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) was tested in air conditioned rearing rooms and tropical netted greenhouses (GHs). Two commercial neem products, NeemAzal®-T/S (1% azadirachtin) and NeemAzal®-U (17% azadirachtin), were used. Foliar application, under room conditions at dose-rates of 7 and 10 ml NeemAzal®-T/S, induced an immature mortality of 32 and 44%, respectively, whereas 7 days post-application, under GH conditions, mortality rates declined to 5 and 7%, respectively. This result indicated rapid dissipation of the active ingredients. However, systemic application by soil drenching resulted in more stable effects under both laboratory and GH conditions. After soil drenching with solutions of 3.0 g NeemAzal®-U until 7-day, immature mortality declined from 88% for the first day to almost half (45%) by day-7 in the GH, and from 90% on first day to 64% by day-7 under laboratory condition. Similar response trends for B. tabaci were obtained for other parameters such as adult colonisation, egg deposition, and egg hatch. The loss of efficiency of the neem products was clearly related to dose-rate, methods of application, and environment (temperature and UV). Soil application is therefore, a convenient approach to achieve high efficiency and persistence with neem products under the conditions in tropical GH environments for whitefly management.  相似文献   

7.
The red flour beetle, Tribolium castaneum (Herbst), is one of the most serious secondary pests that feeds on a wide range of durable stored products including cereals, cereal products and other high value produce such as cocoa beans and dried fruits. Toxicity and protectant potential of Calneem® oil derived from the seeds of the neem tree Azadirachta indica A. Juss. towards T. castaneum were evaluated in stored wheat in the laboratory using contact toxicity, grain treatment, persistency, progeny emergence and repellency assays. Calneem® contains about 0.3% azadirachtin as its major active ingredient. The Calneem® was applied at six dosages (0.1, 0.2, 0.5, 1.0, 2.0 and 3.0% v/v). The oil was emulsified with water using 0.07% soap. All dosages of Calneem® oil were toxic and highly repellent to T. castaneum with an overall repellency in the range of 52–88%. The highest dosage of 3.0% of Calneem® oil tested killed at least 90% of the beetles within 72 h on grain, and 88% mortality was obtained on filter paper. T. castaneum mortality was dose dependent. The development of eggs to adults on cracked wheat was significantly (P < 0.05) inhibited by Calneem® oil treatments. The effectiveness of Calneem® oil was significantly reduced by the length of storage after application. The results obtained suggest good potential for the practical use of Calneem® oil as grain protectant for stored product pest control. The use of plant materials such as neem oil may be a safe, cost-effective method of grain preservation against pest infestation amongst low-resource poor farmers who store small amounts of grains.  相似文献   

8.
Many arthropod predators and parasitoids exhibit either stage-specific or lifetime omnivory, in that they include extra-floral nectar, floral nectar, honeydew or pollen in their immature and/or adult diet. Access to these plant-derived foods can enhance pest suppression by increasing both the individual fitness and local density of natural enemies. Commercial products such as Amino-Feed®, Envirofeast®, and Pred-Feed® can be applied to crops to act as artificial-plant-derived foods. In laboratory and glasshouse experiments we examined the influence of carbohydrate and protein rich Amino-Feed UV® or Amino-Feed, respectively, on the fitness of a predatory nabid bug Nabis kinbergii Reuter (Hemiptera: Nabidae) and bollworm pupal parasitoid Ichneumon promissorius (Erichson) (Hymenoptera: Ichneumonidae). Under the chosen conditions, the provision of either wet or dry residues of Amino-Feed UV had no discernable effect on immediate or longer-term survival and immature development times of N. kinbergii. In contrast, the provision of honey, Amino-Feed plus extrafloral nectar, and extrafloral nectar alone had a marked effect on the longevity of I. promissorius, indicating that they were limited by at least carbohydrates as an energy source, but probably not protein. Compared with a water only diet, the provision of Amino-Feed plus extrafloral nectar increased the longevity of males and females of I. promissorius by 3.0- and 2.4-fold, respectively. Not only did female parasitoids live longer when provided food, but the total number of eggs laid and timing of deposition was affected by diet under the chosen conditions. Notably, females in the water and honey treatments deposited greater numbers of eggs earlier in the trial, but this trend was unable to be sustained over their lifetime. Egg numbers in these treatments subsequently fell below the levels achieved by females in the Amino-Feed plus extrafloral nectar and cotton extrafloral nectar only treatments. Furthermore, there were times when the inclusion of the Amino-Feed was beneficial compared with cotton extrafloral nectar only. Artificial food supplements and plant-derived foods are worthy of further investigation because they have potential to improve the ecosystem service of biological pest control in targeted agroecosystems by providing natural enemies with an alternative source of nutrition, particularly during periods of prey/host scarcity.  相似文献   

9.
Shellac was evaluated as radiation protection for the bacteriumBacillus thuringiensis var.entomocidus againstSpodoptera littoralis larvae. Shellac provided excellent protection toB. thuringiensis. The efficacy of shellac in the protection of entomocidal activity ofB. thuringiensis var.entomocidus against UV irradiation has been studied. Results obtained by the absorbtion and the bioassay of residual entomocidal activity ofB. thuringiensis var.entomocidus after exposure to UV irradiation showed that shellac is an excellent photoprotective agent.  相似文献   

10.
In order to test, under warehouse conditions, the longterm effectiveness of THURICIDE® dust, containingBacillus thrungiensis var.kurstaki (=Serotype H3a, 3b), with a viable spore count of 6 to 10 million per mg, the biopreparation was applied to rye, stored in bulk, on which larvae of the Indian Meal Moth (Plodia interpunctella Hbn.) were fed. From May to October, moth eggs were exposed monthly to rye dusted with 100 mg (320×103 IU) resp. 150 mg (480×103 IU) THURICIDE® dust per 100 g grain respectively. At a concentration of 100 mg 0.2% to 2.4% of the larvae, which hatched from the eggs in May, June and August, survived to the adult stage. No moths were observed in the experiments continued during September and October. At a cocentration of 150 mg, only in the experiments started in June and July 2.7% and 0.1% respectively of the eggs and larve survive to become adults. In the experiments of May, August, September and October, none were stated to have survived. The biopreparation-free control of May, June and July showed that about 75% of the eggs/larvae reached the adult stage, whereas, in August, September and October, untreated eggs and larvac reaching the adult stage amounted to 14% and 1% respectively. In reason of the combination of the efficiency ofBacillus thuringiensis and of the only small amount of surviving larvae due to the low temperatures during autumn and winter months, the surface application of THURICIDE® dust would be promising measure for combatting moth pests in bulk-stored grain.  相似文献   

11.
The entomopathogenic nematodeHeterorhabditis bacteriophora Pionar (HP 88) and the bacteriumBacillus thuringiensis Berliner var.kurstaki were tested in the laboratory against the black cutworm, a widely distributed polyphagous insect pest of vegetables and field crops. The experiment was conducted under 15.7 °C (14 to 19 °C) to simulate the average winter temperature in Egypt. The two biocontrol agents influencedAgrotis ipsilon differently whereH. bacteriophora had a more promising control levels than that ofB. thuringiensis. Generally, nematode concentration of ca 500 infective juveniles/insect vial was highly effective (100% mortality) within nine days post nematode infection. The highest concentration of the bacteriumB. thuringiensis var.kurstaki (2,000 Intern. Units/mg) gave significant larval control after 12 days of bacterial infection. Combined effect of both the nematodes and the bacteria did not result in significantly greater control than that achieved by the nematodes used alone. The present results indicated that nematodes could be used successfully against the black cutworm,Agrotis ipsilon larvae during the winter which is the active season of this insect pest in Egypt.  相似文献   

12.
Thiamethoxam (ACTARA® 25WG) was evaluated for its insecticidal activities against the bamboo powder post beetle Dinoderus minutus Fabricius (Coleoptera: Bostrichidae). The study showed that thiamethoxam had contact toxicity against D. minutus. Based on dose-mortality responses, LC50 values for thiamethoxam against D. minutus ranged from 1.74 to 7.94 μg ml?1. Laboratory and field exposure tests showed that thiamethoxam at concentration of atleast 10 μg ml?1 may have anti-oviposition or anti-feeding effects on D. minutus and can protect post harvest Bambusa vulgaris Schrad. culms against the infestation of this bamboo boring beetle.  相似文献   

13.
A 2-year study on the preference and performance of Lipaphis erysimi on different Brassica species in the field and under greenhouse conditions revealed that rapeseed (B. campestris var. BSH-1, B. campestris var. YSPB-9) and mustard (B. juncea RH-30) were better hosts for this aphid than other Brassica species (B. napus, B. nigra, Eruca sativa, B. carinata). On the first group of plants, the rate of nymphal development, longevity and fecundity of this pest were significantly less than on the second group of plants. Development was significantly prolonged when the aphid was reared on second group of plants.  相似文献   

14.
Two bacterial insecticides,Bacillus thuringiensis H-14 andB. sphaericus 1593 were evaluated for larvicidal potency against mosquito larvae ofAedes aegypti. LC50 values showed thatB.thuringiensis H-14 (4×105 spores/ml) had a higher pathogenicity against fourth larval instars ofA. aegypti thanB. sphaericus (3.1×106 spores/ml) by about 7.75 times. Larval selection with LC90 of both pathogens for 8 successive generations caused a decrease in the susceptibility levels of selected strains ofA. aegypti as compared with the original strain. Moreover, the results indicated that the effect of larval selection with the above bioinsecticides led to an obvious reduction in the egg production and hatchability of eggs produced by mosquito adults that developed from surviving larvae.  相似文献   

15.
测定了椽竹竹材的理化性质,并与毛竹、青皮竹和绿竹竹材进行了比较分析.结果表明:椽竹各竹龄竹材的基本密度、气干密度和全干密度平均值分别为0.523～0.632 g·cm-3、0.656～0.801 g·cm-3和0.658～0.777 g·cm-3,随着竹龄增长各部位竹材密度表现出增大的趋势,3年生以上椽竹竹材基本密度小于参比竹种毛竹和青皮竹,大于绿竹.3年生以上椽竹竹材的平均气干体积于缩率和全干体积干缩率分别为9.6％和13.6％,大于毛竹;各竹龄椽竹竹材径向干缩率大于弦向干缩率和纵向干缩率.3年生以上椽竹竹材的灰分平均含量小于绿竹和青皮竹,酸不溶木素平均含量与青皮竹接近而小于绿竹,综纤维素含量大于80％,多戊糖、热水抽出物、1％NaOH抽出物平均含量均高于青皮竹和绿竹,而苯-醇抽出物平均含量小于青皮竹和绿竹.综合分析,椽竹作为纸浆材具有较高的利用价值.  相似文献   

16.
Truffles, subterranean fruit-bodies of the ectomycorrhizal genus Tuber, are currently cultivated on host trees in plantations, both to offset declining wild production and to extend their geographic distribution. We report the effects of the potting medium and potting method components of two very different seedling production systems on the colonization of Quercus bicolor × Q. robur seedlings by T. aestivum (the Burgundy truffle). Seedlings grown in book planter containers using a peat-based medium were smaller yet much better colonized by T. aestivum than seedlings produced in RPM® (Root Production Method) containers using a ground bark-based RPM medium. In either container method, the peat-based medium supported development of more T. aestivum mycorrhizae than did the RPM medium. Seedlings grown in book planters developed significantly more root tips l?1 of medium than did seedlings grown in RPM containers. The optimum pH for T. aestivum mycorrhiza development in the peat-based medium is between 6.7 and 7.5.  相似文献   

17.
The efficacy of bottom board traps and CheckMite + strips using Coumaphos, for small hive beetle (SHB) diagnosis and control was studied in Australia. Colonies in three apiaries (N = 10 each) were surveyed for SHB. In two apiaries, colonies received bottom board traps (cardboard or plastic) with CheckMite + strips and in the control apiary, traps without strips. After 5 days, all colonies were surveyed again, killed and dissected to quantify non-detected SHB. Significant differences in the number of live SHB were found between apiaries after treatment, supporting the fact that Coumaphos traps are efficient (trap mortality: 94.73 ± 0.06% cardboard and 99.53 ± 0.01% plastic). However, mortality assessment at the colony level (53.29 ± 31.30%), showed that only a limited SHB proportion was affected. Post mortem colony inspections revealed that 14.06 ± 10.53% SHB were undetected, which should be considered for quantitative diagnosis. Bottom board traps provided a first estimate of infestation levels (43.03 ± 27.02%).  相似文献   

18.
Scolytids have been studied more than any other group of forest insects, but most investigations have been restricted to only a few pest species. This bias hampers our understanding of variation in abundance and pest status. Even the simple question whether the abundance of scolytids can predicted by the same independent variables as their pest status is still a matter of debate. To explore this issue, we estimated their abundance using non-attracting flight-interception traps set in a wide range of forests across Czech Republic, Germany, and France. Pest status was taken from current literature. As independent variables, we considered host range, host abundance, and several traits of the considered species in linear models using generalized least squares with a correlation structure derived from the phylogenetic tree of the beetles. Host range was calculated as the root phylogenetic diversity index. The variation in the abundance across scolytids was well explained by resource-related parameters (R2 = 0.53). In contrast to abundance, the pest status was significantly related to species-specific traits, such as body size and maximum number of generations. However, the explained variance was much lower (R2 = 0.19). Although our analysis showed that abundance and pest score follow different patterns, we stress the importance of monitoring all species using non-selective traps. Considering the increasing global trade and the rapidly changing climate, such a broad ecological monitoring is necessary to detect new interactions and/or invading species that may influence our forests ecosystems.  相似文献   

19.
A new intact glucosinolate Cinnamoyl derivative [6'-O-trans-(4″- hydroxy cinnamoyl)-4-(methylsulphinyl) butyl glucosinolate] (A) has been isolated from Broccoli (Brassica oleracea L. var. italica) florets. The compound was isolated and characterized by LC, MS-ESI, FTIR, 1H and 13C NMR as well as 1H-1H COSY, DEPT 135° spectrometric experiments.  相似文献   

20.
The present research dealt with the toxicity of GCSC-BtA (Germany–China Scientific Cooperation-Bacillus thuringiensis-Abamectin), a new type biocide developed by conjugating a toxin from Bacillus thuringiensis (B.t.) with Abamectin from Streptomyces avermitilis, on arthropod pests under different temperature conditions. The results showed that GCSC-BtA possessed higher toxicity than B.t. crystal, Abamectin or Cypermethrin, with pest mortalities of 97.9, 93.7, 96.4, 82.3 and 96.7% for Tetranychus cinnabarinus (Boisd.) (Acari, Tetranychidae), Frankliniella occidentalis Pergande (Thys., Thripidae), Aphis fabae Scopoli (Hom., Aphididae), Plutella xylostella (L.) (Lep., Plutellidae) and Cameraria ohridella Deschka et Dimić (Lep., Gracillariidae), respectively. Toxicities of GCSC-BtA to T. cinnabarinus and P. xylostella decreased significantly at the older developmental stage with an exception that egg stage had the highest tolerance, in which LC50s of GCSC-BtA were 0.0001, 0.0019 and 0.0708 mg/ml for nymph, adult and egg of T. cinnabarinus, and that 0.0399, 0.2035 and 0.9033 mg/ml for the 2nd instar larvae, 4th instar larvae and egg of P. xylostella, respectively. Also, the biocide was more effective to the lower stage of A. fabae than the higher one with LC50s of 0.0023, 0.0086 and 0.0171 mg/ml against 1st instar nymph, 3rd instar nymph and adult, respectively. In general, toxicity of the new type of biocide was positively related to temperature against all the tested pests, except against T. cinnabarinus, where it was almost similar at the three temperature conditions. GCSC-BtA displayed significantly lower toxicities at 15/20°C than 20/25°C or 25/30°C against F. occidentalis, A. fabae, P. xylostella and C. ohridella. However, no significant difference was found in the toxicities against F. occidentalis, A. fabae and C. ohridella above 20°C, whereas toxicity against P. xylostella increased as temperature raised. Therefore, to achieve higher efficacy in the field, application rate and time should be devised according to these factors.  相似文献   

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