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1.
We herewith report for the first time the discovery in Israel of the invasive species Corythauma ayyari (Drake), a member of the lace-bug family, Tingidae (Hemiptera).  相似文献   

2.
Lai T  Su J 《Pest management science》2011,67(11):1468-1472
BACKGROUND: Beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), is a major pest of numerous cultivated crops. Chlorantraniliprole, the first commercialised ryanodine receptor insecticide from the anthranilic diamide class, has exceptional insecticidal activity on a range of lepidopteran pests. The aim of this study was to assess the resistance of S. exigua to chlorantraniliprole in the laboratory. RESULTS: A field‐collected population of S. exigua was selected after repeated exposure to chlorantraniliprole to determine the risk of resistance evolution. After 22 generations of selection, there was a 12.0‐fold increase in LC50. The realised heritability (h2) of resistance was estimated as 0.1082 by using threshold trait analysis. The projected rate of resistance evolution indicated that, if h2 = 0.1082 and 70% of the population was killed at each generation, then a tenfold increase in LC50 would be expected in 21.7 generations for chlorantraniliprole. CONCLUSION: These results show that the risk of resistance development to chlorantraniliprole exists in S. exigua after continuous application. Copyright © 2011 Society of Chemical Industry  相似文献   

3.
Field efficacies of two insect growth regulators (IGRs) at two recommended application rates, buprofezin at 370 and 555 g AI ha(-1) and lufenuron at 37 and 49 g AI ha(-1), were determined against the sweet potato whitefly, Bemisia tabaci (Gennadius), and the cotton bollworm, Helicoverpa armigera (Hübner), in experimental plots of cotton at the Directorate of Cotton Research, Faisalabad, Pakistan. Adverse effects of the IGRs on populations of associated arthropod predators, namely geocorids, chrysopids, coccinellids, formicids and arachnids, were also assessed. Both IGRs significantly reduced populations of B. tabaci at each application rate 24, 48 and 72 h after treatment, and higher doses were more effective than lower doses. Buprofezin was not effective against H. armigera at any tested dose for any time of treatment in any spray. Lufenuron applied at 37 and 49 g AI ha(-1) effectively suppressed H. armigera populations, resulting in significant reductions in crop damage. At lower doses, both IGRs appeared safe to predator populations, which did not differ significantly in IGR-treated versus untreated control plots. Population densities of formicids and coccinellids were significantly lower at high concentrations of both IGRs in treatment plots, possibly as a result of reduced prey availability. The potential role of buprofezin and lufenuron for control of B. tabaci and H. armigera in a spray programme and the likelihood of direct toxic effects of IGRs on predatory fauna of cotton are discussed.  相似文献   

4.
The changes in the susceptibility of the cotton bollworm, Helicoverpa armigera (Hübner) to three insecticides (lambda-cyhalothrin, phoxim and endosulfan) commonly used for control of this pest in China were monitored by bioassays at various generations. The insects were originally collected from Bt cotton fields and selected with Cry1Ac over 44 generations. In comparison with a susceptible strain, the larval resistance of the Bt-selected populations to Cry1Ac toxin increased 106-fold. Simultaneously, the resistance levels to lambda-cyhalothrin, phoxim and endosulfan declined dramatically. The results indicated no positive cross-resistance between Cry1Ac toxin and the insecticides. Evidence of the lack of cross-resistance to three commonly used synthetic insecticides in our laboratory-derived Cry1Ac-resistant population may suggest that growers can confidently use these insecticides if and when resistance to Cry1Ac cotton does occur.  相似文献   

5.

Two-way effects of herbicide on rice resistance and multiplication and feeding of the rice brown planthopper (BPH), Nilaparvata lugens (Stål) were studied. Four of 11 herbicides tested, butachlor, metolachlor, oxadiazon and bentazone, had significantly stimulating effects on multiplication and feeding of BPH. Multiplication times (N 1/N 0) of BPH on the rice treated with the four herbicides were 674, 367, 322 and 311, respectively, while that of N. lugens on the untreated plants was 159. The results of measurements of honeydew production by BPH indicated that the feeding rates of the brown planthoppers increased when the insects fed on the plants treated with bentazone, quinclorac, oxadiazon and quinclorac. Survival rates of N. lugens first to third-instars rose on the rice plants treated with butachlor, bentazone, but that of the fourth and fifth instars were not affected. Furthermore, all of those herbicides tested led to a decline of rice resistance, i.e. the injury scales of the treated plants were larger than that of the control under the same pest stress. Based on their effects on rice resistance and on BPH, the herbicides tested can be divided into two categories, one affecting rice resistance and BPH multiplication, the other affecting rice resistance only.  相似文献   

6.
BACKGROUND: This study focused on determining the minimal effective gamma radiation dose that prevents commodity damage caused by the Indian meal moth Plodia interpunctella (Hübner). The study was also designed to assess the effect of releasing either partially sterilized males alone or both partially sterilized males and females on the reproductive potential of P. interpunctella populations. RESULTS: The dose of radiation required to prevent larval emergence from irradiated eggs was 350 Gy, and the same dose was also required to prevent adult emergence from mature larvae. A dose of 300 Gy was not able to prevent adult emergence from irradiated pupae. The dose at which 100% sterility was achieved in treated females mated to treated males was 300 Gy for the parental generation of irradiated pupae. Fertility of the parental males from irradiated pupae was 48.17% at 300 Gy in treated males crossed with untreated females, but male progeny of irradiated male parents had a residual fertility of 11.06% at the same dose. CONCLUSION: F(1) males from irradiated pupae were more sterile than parental males. To prevent larval emergence from irradiated eggs, a dose of 350 Gy is required. The same dose is required to prevent the larvae from reaching the adult stage.  相似文献   

7.
Pyrethroid resistance in field populations of Australian Helicoverpa armigera (Hübner) is primarily a consequence of the overproduction of esterase isoenzymes which metabolise and sequester pyrethroid insecticides. Biochemical studies have shown that pyrethroid-resistance-associated esterases in H armigera are inhibited by the insecticide synergist piperonyl butoxide (PBO). Esterase inhibition by PBO did not occur immediately after dosing, but exhibited maximum inhibition 3-4 h after dosage. Esterase activity subsequently recovered until full activity was restored by 24 h. Topical bioassays using a pre-treatment of PBO showed that maximum H armigera mortality was achieved with pre-treatment times corresponding to maximum esterase inhibition. These results demonstrated that, with correct temporal application, PBO can restore pyrethroid efficacy against H armigera. It would also be expected that restoration of efficacy with other conventional insecticides, currently compromised by esterase-based resistance mechanisms, would occur.  相似文献   

8.
Liu X  Zhang Q  Xu B  Li J 《Pest management science》2006,62(8):729-737
In the laboratory, the percentage mortality and pupation of Helicoverpa armigera (Hübner) were investigated when larvae were exposed to Cry1Ac of Bacillus thuringiensis Berliner, nuclear polyhedrosis virus of H. armigera (HaNPV) or Cry1Ac and HaNPV together. The results revealed that interactions between Cry1Ac and HaNPV varied with bioassay method and concentration of the suspension. When larvae were infected using a suspension containing both HaNPV and Cry1Ac, most combinations of Cry1Ac (62.5, 125 and 250 microg mL(-1)) and HaNPV (1.2 x 10(6), 6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae were force fed diet containing Cry1Ac 48 h after being infected by HaNPV, interaction between Cry1Ac (0.5, 1, 2, 4 and 8 microg mL(-1)) and HaNPV (6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an additive effect, while combinations of Cry1Ac (0.5, 1, 2 and 4 microg mL(-1)) and HaNPV (1.2 x 10(6) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae being infected by HaNPV were fed on Cry1Ac diet from neonate to death or pupation, the results suggested that Cry1Ac and HaNPV showed an additive interaction. The percentage mortality was lower in the treatment of larvae infected by transgenic Bt cotton leaf discs containing HaNPV suspension than in the treatment of larvae by conventional cotton leaf discs containing HaNPV, while the pupation rate was higher. The combination of Bt cotton and HaNPV showed antagonism. The present results showed that a combination of Cry1Ac and HaNPV usually resulted in mortality levels greater than in the case of Cry1Ac but not greater than with the virus alone.  相似文献   

9.
10.
Abstract: The adult male of dracunculoid nematode Ichthyofilaria argentinensis Incorvaia, 1999 (Guyanemidae) is described for the first time based on specimens found in the swimbladder of its type host, Merluccius hubbsi Marini (Merlucciidae), caught off the coast of Buenos Aires, Argentina (western Atlantic Ocean). In addition, the males of Ichthyofilaria bergensis (Wülker, 1930) K?ie, 1993 are redescribed from specimens collected from the body cavity and visceral surface of Molva macrophthalma (Rafinesque) (Lotidae) caught in the western Mediterranean Sea, off the coast of Sardinia. Light and scanning electron microscopy examinations revealed some new morphological features for the genus, such as a pair of deirids located near the end of muscular oesophagus, the body wall conspicuously twisted immediately anterior to the cloaca, the presence of a copulatory plate, one pair of adcloacal papillae and a pair of phasmids situated on the posterior half of the tail. On the basis of this material, the generic diagnosis of Ichthyofilaria is modified to include some of these newly observed features, as well as to indicate the absence of spicules. The diagnosis of Guyanemidae is extended to include that a copulatory plate and/or two spicules may be present as characteristics for this family.  相似文献   

11.
Journal of Plant Diseases and Protection - The names of the varieties cultivated in the two study regions were given wrongly in the Materials and Methods section. The correct names are as follows.  相似文献   

12.
We investigated the sub-lethal influences of spinosad, chlorpyriphos, endosulfan, acephate and cypermethrin on the oviposition responses of Helicoverpa armigera (Hübner) to cotton plants, under cage and laboratory conditions. The rank order of toxicity (LC50 values as a per cent) of test insecticides against third instar larvae using the leaf disc method was: spinosad > chlorpyriphos > endosulfan > acephate > cypermethrin. On whole plants, females laid more eggs on acephate LC50-, acephate LC30- and cypermethrin LC50-treated cotton plants than on the control. The chlorpyriphos-treated plants were least preferred for oviposition. When excised cotton leaves from different treatments were used in a multiple-choice test, cypermethrin LC50- and endosulfan LC30-treated leaves received more eggs than the control. The repeated application of sub-lethal concentrations of different insecticides reduced plant height in the case of acephate LC30 and cypermethrin LC50, while plant spread and upper canopy leaf area were reduced in both treatments of acephate and cypermethrin. Reduced plant spread, upper canopy leaf area followed by plant height were found associated with oviposition preference by H. armigera females.  相似文献   

13.
Journal of Plant Diseases and Protection - Cecidochares connexa is currently the only effective biological control agent of Chromolaena odorata an invasive weed in West Africa. Recently, an...  相似文献   

14.
The brown marmorated stink bug. Halyomorpha halys, (BMSB) is an exotic pest causing damage to fruits and vegetables. They also transmit diseases. Integrated pest management strategies are lacking for this invasive. For the first time, information is presented on the virulence of several entomopathogenic fungi against BMSB. Three Beauveria bassiana and two Metarhizium anispoliae isolates were bioassayed against adult BMSB. One B. bassiana isolate was the active ingredient in BotaniGard® which produced 85 and 100% mortality in 9 and 12 days post treatment, respectively. Experimental isolates ERL 1170 and ERL 1540 were also efficacious. Metarhizium anispoliae isolates produced lower mortalities than the B. bassiana isolates. Data presented showed the potential for management of BMSB with entomopathogenic fungi. Copyright © 2012 Society of Chemical Industry  相似文献   

15.
The herbicidal activity of the pyridine derivative LS 82–556 [(S)3-N-(methylbenzyl)carbamoyl-5-propionyl-2,6-lutidine] has been studied on green or etiolated seedlings of cucumber (Cucumis sativus L. cv Vert Long Maraîcher), wheat (Triticum aestivum L. cv Fidel), and maize (Zea mays L. cv Monclair). The symptoms were strictly light dependent, and consisted of bleaching, wilting, and desiccation of leaves and stems. In green seedlings pretreated for 24 hr in the dark with 10 μM LS 82–556, increases in ethane evolution and thiobarbituric acid-reacting material content could be detected after a 3-hr exposure to high light intensity (400 μE m−2 sec−1 photosynthetically active radiation). Similar increases were also detected in etiolated seedlings. Electron microscope observations of treated tissues exposed to light for 6 hr or more revealed structural damage at the level of cellular membranes (chloroplast envelope, tonoplast, and plasma membrane). In cotyledons or leaves grown in the light, activity of LS 82–556 required the presence of chloroplastic pigments. All the above results suggest that as for diphenyl ether herbicides, the mechanism of action of LS 82–556 involves photooxidative reactions leading to the degradation of fatty acids. A further analogy between the two types of herbicide action comes from their similar requirement for an operating photosynthetic electron flow when they are administered to green tissues.  相似文献   

16.
BACKGROUND: The cotton bollworm, Helicoverpa armigera (Hübner), is one of the most serious insect pests of cotton. It has developed resistance to almost all groups of chemical insecticides because of their intensive use. The failure of insecticides to control H. armigera has been a strong incentive for the adoption of transgenic cotton (Bt cotton). However, the value of Bt could be diminished by widespread resistance development to Bt toxins in insect populations. Therefore, understanding the genetic basis of resistance is essential for developing and implementing strategies to delay and monitor resistance. RESULTS: A resistant strain designated as BM‐R was obtained from the cross of adults from Bathinda () and Muktsar (), Punjab, India, which showed the highest survival (60.68%) and LC50 value (1.396 µg mL?1 diet). Similarly, a laboratory‐maintained strain from Hoshiarpur, Punjab, showed maximum susceptibility to Cry1Ac toxin with the lowest LC50 value (0.087 µg mL?1), and was designated as HP‐S. The genetic purity of both strains was confirmed by RAPD profile analysis at each generation, and genetic similarity reached more than 90% after the third generation. Continuous maintenance of the resistant BM‐R strain on Cry1Ac resulted in an increase in LC50 from 0.531 µg mL?1 in F0 to 4.28 µg mL?1 in F14 and 7.493 µg mL?1 in F19, while the LC50 values for HP‐S larvae on diet without Cry1Ac increased to 0.106 and 0.104 µg mL?1, which lay within the fiducial limits of the baseline LC50 value. The mode of inheritance of resistance was elucidated through bioassay response of resistant, susceptible heterozygotes and backcross progeny to Cry1Ac incorporated in semi‐synthetic diet. CONCLUSION: Based on dominance, degree of dominance and backcross values, resistance was inferred to be polygenic, autosomal and inherited as a recessive trait. Copyright © 2011 Society of Chemical Industry  相似文献   

17.
Wang Y  Chen J  Zhu YC  Ma C  Huang Y  Shen J 《Pest management science》2008,64(12):1278-1284
BACKGROUND: In recent years, outbreaks of the brown planthopper, Nilaparvata lugens (Stål), have occurred more frequently in China. The objective of this study was to determine the susceptibility of N. lugens to neonicotinoids and other insecticides in major rice production areas in China. RESULTS: Results indicated that substantial variations in the susceptibility to different insecticides existed in N. lugens. Field populations had developed variable resistance levels to neonicotinoids, with a high resistance level to imidacloprid (RR: 135.3–301.3‐fold), a medium resistance level to imidaclothiz (RR: 35–41.2‐fold), a low resistance level to thiamethoxam (up to 9.9‐fold) and no resistance to dinotefuran, nitenpyram and thiacloprid (RR < 3‐fold). Further examinations indicated that a field population had developed medium resistance level to fipronil (up to 10.5‐fold), and some field populations had evolved a low resistance level to buprofezin. In addition, N. lugens had been able to develop 1424‐fold resistance to imidacloprid in the laboratory after the insect was selected with imidacloprid for 26 generations. CONCLUSION: Long‐term use of imidacloprid in a wide range of rice‐growing areas might be associated with high levels of resistance in N. lugens. Therefore, insecticide resistance management strategies must be developed to prevent further increase in resistance. Copyright © 2008 Society of Chemical Industry  相似文献   

18.
19.
本文记述贵州省分布的猎蝽科瘤蝽亚科昆虫4种,其中滇龟瘤蝽Chelocoris yunnanus HsiaoLiu,1965,宝兴螳瘤蝽Cnizocoris potanini(Bianchi,1899)和小菱瘤蝽Amblythyreus potaninae(Bianchi,1899)为贵州首次记录,并提供了所有种类的整体背面观、头和前胸背板侧面观的彩色照片。  相似文献   

20.
It has been reported previously that the major resistance mechanism to pyrethroid insecticides by the cotton bollworm Helicoverpa armigera (Hübner) in Australia is a consequence of overproduction of esterase isoenzymes. This paper reports structure-activity relationships that support such a view, based on in vivo bioassays conducted with a range of pyrethroid structures containing a variety of acid and alcohol moieties and the correlation with in vitro esterase inhibition assays against the same structures, and identifies the critical regions of the molecule with regard to esterase inhibition, and hence resistance. The implications of this work in terms of possible resistance management are evaluated and discussed.  相似文献   

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