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Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objectives] To clarify the toxicological effect of sublethal doses of avermectin on Hyphantria cunea, and thereby provide a theoretical basis for the rational use of this pesticide. [Methods] The growth and development of 4th to 6th instar H. cunea larvae were measured after these had consumed artificial diets containing sublethal concentrations of abamectin (LC10 or LC30) for 72 h. Control groups were fed an aqueous solution containing 0.1% dimethyl sulfoxide. The reproductive ability of adults obtained from these treatment groups was also measured. [Results] The 4th instar LC30 treatment group grew 22% less than the respective control group (P<0.05), whereas there were no significant differences in growth between the 5th and 6th instar LC30 treatment groups and their respective control groups (P>0.05). There was no significant difference in growth between the LC10 treatment groups and their respective control groups (P>0.05). Development of the 4th, 5th and 6th larval instars in the LC30 treatment groups (3.4, 2.2 and 1.7 days, respectively) was significantly prolonged relative to the respective control groups (P<0.05), but there was no significant difference in the duration of development of the LC10 treatment groups (P>0.05) and the respective control groups. Adult longevity in the LC10 and LC30 treatment groups (1-1.7 and 2.3-2.7 days, respectively) was significantly shorter than that of the respective control groups (P<0.05). The pupation rate, emergence rate, fecundity and hatching rate of the LC10 and LC30 treatment groups were also significantly shorter compared to the respective control groups (P<0.05). Pupation and emergence rates, fecundity, and hatching rate in the LC30 treatment group were 36%-56%, 33%-66%, 49%-78% and 45%-62%, respectively, those of the respective control groups. The fecundity and hatching rate of the LC10 treatment groups were 66-88% and 62-82%, respectively, those of the respective control groups. Only the feeding, larvae period, emergence rates and pupation rates of 4th instar larvae, the larvae period and emergence rates of 5th instar larvae, and the emergence rates and egg hatching rate of 6th instar larvae, were significantly less in the LC10 and LC30 treatment groups than in the respective control groups; the differences were greater for the LC30 treatment group than for the LC10 treatment group. [Conclusion] Exposure of H. cunea larvae to sublethal concentrations of abamectin (LC10 and LC30) inhibits both larval growth and development and the reproductive capacity of larvae that survive to adulthood. [ABSTRACT FROM AUTHOR]

[Objectives] To clarify the influence of sex, age (days) and temperature, on the flight ability of adult Hyphantria cunea, and there by provide information essential for monitoring, and predicting, the dispersal of this pest. [Methods] The effect of gender, age and temperature on the flight ability of adult H. cunea was measured in an insect flight mill. [Results] Males were significantly stronger fliers than females with a maximum flight distance of 17.87 km and cumulative flight time of 17.38 h. One day-old males had the longest cumulative flight distance; the average cumulative flight distance and average cumulative flight time of males decreased with age. The maximum female flight distance was 8.21 km and the longest cumulative flight time was 7.4 h. Female flight distance tended to first increase, then decrease, with age. Three day-old females had the maximum cumulative flight distance. A two-way ANOVA of the average cumulative flight distance, average cumulative flight time, and average flight speed, did not detect a significant interaction between sex and age. Male flight speed was significantly slower at a temperature of 16 °C. [Conclusion] Male H. cunea are stronger fliers than females. Male flight ability gradually decreases with age, whereas that of females tends to increase up to 3 days of age, then decrease. Low temperatures reduce the flight speed of H. cunea males. [ABSTRACT FROM AUTHOR]

[Objectives] To determine the optimal reproduction and storage conditions for the Hyphantria cunea nudeopolyhedrovirus (HcNPV) in order to provide a theoretical basis and technological support for the commercial production of this virus. [Methods] The effects of different larval instars, virus concentration, duration, temperature and population density, were analyzed to identify the optimal condition for HcNPV reproduction in vivo. Effects of different formulations, times, temperatures and adjuvants on the stability of HcNPV storage were also investigated to determine the optimal HcNPV bioactivity assay method. In feeding bioassays, the number of proliferating occlusion bodies (OB) were recorded with a hemocytometer, and the lethal time (LT50) was calculated to quantify the insecticidal activity of HcNPV Third instar larvae fed a diet with a HcNPV concentration of 1x106 OBmL-1 were used for follow-up experiments. [Results] OB proliferation in 5th instar larvae reared on an artificial diet containing HcNPV at a concentration of 1x106 OBmL-1 was significantly higher (1.16x1010 OB per larva) than in other treatments. The optimal temperature for HcNPV reproduction was 20 °C, which resulted in 5.06x109 OB per larva. The abundance of HcNPV virions significantly decreased from 3.42x109 OB per larva after feeding for 1 day to 0.97x109 OB per larva after feeding for 5 days. Larvae kept at a density of 100 larvae/box (0.05 larvae/cm²) had 4.94x109 OB per larva, which was significantly higher than that of those kept at densities of 200, 300, 400, 500 larvae/box. The LT50 of 3rd instar larvae infected from insect pulp and freeze-dried insect pulp was significantly lower than that of those infected from virus suspension and freeze-dried virus suspension. There was no significant change in the insecticidal activity of HcNPV when stored for less than 12 months and insecticidal activity did not change significantly over a range of storage temperatures from - 20 to 25 °C. The best preservatives were sucrose (50%) and sodium chloride (5%), which had in LT50 values of 4.94 days and 4.97 days, respectively. [Conclusion] The highest yield of HcNPV was achieved by giving 5th instar H. cunea larvae a single feed of an artificial diet containing HcNPV inoculum at a concentration of 1x106 OB mL-1 and keeping larvae at a density of 0.05 larvae/cm² at a temperature of 20 °C. Grinding the bodies of diseased larvae into a slurry, adding sucrose (50%) or sodium chloride (5%) as adjuvants, and storing the resultant homogenate in a refrigerator at - 20 °C, allowed HcNPV to be stored for up to 12 months with no loss in insecticidal activity. [ABSTRACT FROM AUTHOR]

Hyphantria cunea has many hosts, a broad distribution, caused serious economic damage, is difficult to control, and has seriously affected the development of forestry in China. Control of this pest mainly relies on a combination of chemical and biological methods, including the use of sex pheromones traps and monitoring population dynamics in combination with chemical and biological control. However, developing more sustainable and effective methods for controlling of H. cunea has always been a focus of research on this species. This paper reviews the current distribution of H. cunea in China, problems in the prevention and control of this pest, and progress in the application of ecological control. It also introduces new control technologies, such as genetically-modified sterile insect technology, RNAi and Bt transgenic insect-resistant tree species. Finally, it forecasts the future trends in the development of H. cunea control methods [ABSTRACT FROM AUTHOR]

[Objectives] To compare the insecticidal activity of four commonly used insecticides; emamectin benzoate, beta-cypermethrin, chlorobenzuron and matrine, on the larvae of Hyphantria cunea (Drury), in order to determine which have a significant synergistic interaction with the Hyphantria cunea nuclear polyhedrosis virus (HycuNPV). [Methods] Groups of 3rd instar larvae of H. cunea infected with HycuNPV were treated with one of the four chemical insecticides above using the artificial feed surface coating method. The synergistic interaction between each insecticide and HycuNPV was then evaluated using the co-toxicity factor method. Those insecticides with a significant synergistic effect were identified, and the optimal pesticide: virus ratio and concentration was determined. [Results] The relative toxicity of the four insecticides tested was: emamectin benzoate >beta-cypermethrin>chlorobenzuron>matrine, and their median lethal concentrations (LC50) were 0.021, 2.149, 4.522 and 70.255 mg-L-1, respectively. A combination of emamectin benzoate (0.021 mg-L-1) and HycuNPV(1.18x106 OBs mL-1) had a significant synergistic effect. A pesticide: virus volume ratio of 1-9 resulted in a 29.06 fold increase in mortality and a 2.89 day reduction in the median lethal time (LT50) compared to HycuNPV in isolation. [Conclusion] Among the insecticides tested, emamectin benzoate had both the highest toxicity to 3rd instar H. cunea larvae, and the greatest synergy with HycuNPV. Optimum toxicity was achieved at a concentration of 0.021 mg L-1 emamectin benzoate and 1.18x106 OBsmL-1 HycuNPV and a volume ratio of 1:9. [ABSTRACT FROM AUTHOR]

[Objective] To investigate the selection and feeding adaptability of Hyphantria cunea with respect to eight widely distributed and planted trees in Heilongjiang province. [Methods] The behavioral responses of 4th instar larvae and male and female adults to the leaf odors of Tilia amurensis, Phellodendron amurens, Populus simonii, Larix gmelinii, Quercus mongolica, Fraxinus mandshurica, Syringa oblata and Betula platyphylla were measured in a Y-type olfactometer. The leaves of a single tree species and 4th instar larvae of H. cunea were placed in the olfactometer and the feeding rate of larvae on the leaves was determined after 24 hours. [Results] Unmated female moths significantly preferred the leaves of all tree species, except of L. gmelinii, to the control (P<0.05). Mated female moths significantly preferred the leaves of T amurensis, P. .simonii, Q. mongolica and F mandshurica to the control (P < 0.05). However, unmated male moths showed no significant preference for the leaves of all eight tree species over the control. Fourth instar larvae significantly preferred the leaves of T. amurensis, P. amurense, P. simonii, Q. mongolica, F. mandshurica and B. platyphylla to the control (P < 0.05). Fourth instar larvae fed significantly more on T. amurensis leaves than they did on those of P. simonii, P. amurense, L. gmelinii, Q. mongolica, F. mandshurica or S. oblata (P < 0.05). They also fed significantly more on the leaves of B. platyphylla, P. .simonii, P. amurense, L. gmelinii, Q. mongolica and F. mandshurica than on those of S. oblata (P<0.05). [Conclusion] Female adults and 4th instar larvae of H. cunea preferred the odour of leaves T. amurensis, P. simonii, Q. mongolica and F. mandshurica to those of P. amurens, L. gmelinii, S. oblata or B. platyphylla, and fourth instar larvae also consumed significantly more of the leaves of these species than those of S. oblata. These results suggest that T. amurensis, P. simonii, Q. mongolica and F. mandshurica could be suitable hosts for the growth and development of H. cunea. [ABSTRACT FROM AUTHOR]

[Objectives] To clone the Hyphantria cunea glutathione S-transferases (GST) gene (HcGST-E1 ) and verify the role of this gene in the response of H. cunea to quercetin, a common secondary substance in host plants. [Methods] HcGST-E1 was cloned based on the quercetin-induced midgut transcriptome of H. cunea and real-time, quantitative PCR results. The gene was then silenced using RNAi technology and the effect of this on the weight and survival of quercetin-treated 4th instar larvae investigated. [Results] The HcGST-E1 was successfully cloned and silenced. dsHcGST-E1 effectively inhibited the expression of HcGST-E1 with a maximum silencing efficiency of 62.3%. Over the same period of time, 1 000 ng of dsHcGST-E1 was more effective than 500 ng dsHcGST-E1. The survival rates of HcGST-E1 silenced larvae that had been fed an artificial diet containing either 0.5% or 1.0% quercetin were 40.00% and 33.33%, respectively, significantly lower than their respective control groups (73.33% and 66.67%; P < 0.05) or blank control groups (86.67% and 80.00%; P < 0.05) . The body weight of HcGST-E1 silenced H. cunea larvae did not fluctuate significantly, and their weight was lower than that of larvae in both respective, and blank, control groups. Larvae in the 5% quercetin treatment group were not significantly lighter than those in the respective control group, but were significantly lighter than those in the blank control groups on day 6 (P < 0.01). Similarly, larvae in the 1.0% quercetin treatment group were not significantly lighter than those in the respective control group, but were significantly lighter than those in the blank control groups on days 4 and 6 (P <0.05). [Conclusion] Silencing the HcGST-E1 gene increased the susceptibility of H. cunea larvae to quercetin, retarding their growth and development. This indicates that HcGST-E1 plays a role in the detoxification and metabolization of quercetin. These results provide a basis for further research on the role of GST genes in the resistance of H. cunea to plant secondary compounds. [ABSTRACT FROM AUTHOR]

[Objectives] To predict the future range of the Fall Webworm (Hyphantria cunea) in China in order to improve the prevention and control of this pest. [Methods] Records of the Fall Webworm collected in China from 2003 to 2020 were obtained and organized, and 19 bioclimatic variables for that period were calculated based on the monthly maximum and minimum temperatures and monthly precipitation. DEM data were obtained and future climate variables under different climate scenarios were calculated. The nine most important environmental variables were identified by VIF and Spearman's rank correlation. Suitable current, and future, habitat for the Fall Webworm were then predicted based on an integrated Biomod2 model. [Results] Suitable habitat for the Fall Webworm is currently concentrated in Liaoning, Shandong, Hebei, Anhui and other provinces. The range of the Fall Webworm is predicted to increase under different climate scenarios, with the overall trend being an expansion of the species' range into northeastern and southern China. [Conclusion] The results provide early warning of areas likely to be colonized by the Fall Webworm, allowing appropriate control measures to be implemented beforehand to prevent its spread. [ABSTRACT FROM AUTHOR]

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The fall webworm, Hyphantria cunea, is a significant worldwide pest, and its sex pheromone includes two alkenals and three epoxy olefins, which can be used to trap H. cunea and monitor population dynamics, and have a promising application. According to the synthesis of aldehyde, the preparations of alkenals include biomimetic synthesis, Weinreb amide method, enzyme catalyzed reaction, iridium-catalyzed hydrosilylation of esters, or cobalt-catalyzed hydrosilylation of esters; whereas on the basis of the linking approaches of key intermediates, the synthetic methods of epoxy olefins, such as thiocyanatocuprate method, Wittig coupling, alkynyl lithium reagent substitution, Gilman reagent substitution and alkylative epoxide rearrangement, were summarized. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Entomology is the property of Chinese Journal of Applied Entomology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Forest Research is the property of Forest Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The determinations of super-cooling ability and body' s water and fat contents of overwintering Hyphantria cunea pupae showed that during overwintering, the female and male H. cunea pupae had the similar change patterns in their cold-resistance ability, i.e., increased with decreasing air temperature, but their body's water and fat contents, super-cooling point (SCP), and freezing point (FP) differed at different overwintering stages. The SCP was significantly lower at pre- and mid-overwintering stages than at late-overwintering stage, while FP had less difference among the stages. The body's water content was significantly higher at mid-overwintering stage than at pre- and late-overwintering stages. Comparing with non-overwintering pupae, the overwintering pupae had significantly lower SCP and FP, but significantly higher body's water and total fat contents. Regression analysis showed that there was a negative relationship between the water content and the SCP of female and male pupae (P < 0.05). [ABSTRACT FROM AUTHOR]