• Title/Summary/Keyword: oviposition

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Effect of adult population density on egg production in the black soldier fly, Hermetia illucens (Diptera: Stratiomyidae)

  • Park, kwanho;Kim, Wontae;Kim, Eunsun;Choi, Ji-Young;Kim, Sung-Hyun
    • International Journal of Industrial Entomology and Biomaterials
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    • v.33 no.2
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    • pp.92-95
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    • 2016
  • The black soldier fly is economically important because its prepupae are used as feed for many animals, including fish and swine. In Korea, black-soldier-fly farms have attempted to increase annual breeding and mass egg production for use in animal feed, as well as the decomposition of organic waste. Such efforts require an understanding of optimal mating and oviposition techniques. Specifically, adult densities and cage size may both improve the efficiency of mass egg production. Our study used four sizes of nylon cages ($1.0{\times}1.0{\times}2.5m$, $1.5{\times}1.5{\times}2.5m$, $2.0{\times}2.0{\times}2.5m$, $2.5{\times}2.5{\times}2.5m$) and three density treatments (4 kg, 8 kg, and 10 kg of pupae) to investigate optimal habitat size and adult density. We found that cage size (independent of density) did not significantly influence female fecundity (number of egg clutches and egg weight), whereas higher densities increased egg number and weight regardless of cage size. Thus, we recommend manipulating adult density to enhance productivity in commercial black-soldier-fly farming. However, we also propose further detailed research to develop methods that account for seasonal changes and environmental conditions, as climatic variables (temperature, sunlight) likely influence female fecundity as well.

Influence of Chilling Duration on Oxygen Consumption and Hatchability in Eggs of the Silkworm, Bombyx mori

  • Yoon, Hyung-Joo;Kim, Sam-Eun;Kim, Jong-Gill;Park, Ji-Young
    • International Journal of Industrial Entomology and Biomaterials
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    • v.8 no.1
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    • pp.73-76
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    • 2004
  • The rate of oxygen consumption of the silkworm eggs was measured to set up the barometer for measuring the effect of egg chilling on diapause termination. In diapause eggs, $O_2$ uptake showed a maximum of 79.2 ${mu}ell$/mg eggs/hr, at one day after oviposition and then gradually decreased to 2.2${mu}ell$/mg eggs/hr at 9days. The rates of oxygen uptake of eggs raised immediately after HCl-treatment and reached to a maximal level of 484.5 ${mu}ell$/mg eggs/hr in 9-day-old eggs, which corresponds to 220 fold that of diapause eggs, and the hatching ability was also over 50%. In order to break diapause, eggs incubated at $25^{\circ}C$ for 30 days after oviposition had to be kept at least for 45 days at 5$^{\circ}C$, but chilled eggs for 90 days or longer hatched at 10 days as normal hatching periods. We also investigate periods which the value of $O_2$ uptake of eggs chilled during 15 to 120 days at 5$^{\circ}C$ reached at 200 ${mu}ell$/mg eggs/hr. As a result of that, $O_2$ uptake of eggs chilled during 15 to 45days were not reached at 200 ${mu}ell$/mg eggs/hr and longer the chilling durations are, the higher the rate of $O_2$ uptake is and the longer the chilling durations are, the shorter the periods up to hatching is. And also, hatch-ability increased rapidly as $O_2$ uptake reaches over 20/eggs/hr.

Analysis of Diapause-Associated Changes in Silkworm Egg Proteins

  • Go, Hyun-Jeong;Hwang, Jae-Sam;Kim, Young-Tae;Kim, Hyun-Su;Kang, Seok-Woo;Chang, Jong-Su;Lee, Sang-Mong;Lee, Bong-Hee;Seong, Su-Il
    • International Journal of Industrial Entomology and Biomaterials
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    • v.9 no.1
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    • pp.117-121
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    • 2004
  • The patterns of diapause-associated proteins of silkworm eggs were analyzed by two-dimensional (2-D) gel electrophoresis. Among the hundreds of spots on the 2-D gels, at least two proteins were considered to be associated with diapause. A protein, spot 4, with an approximate molecular weight of 38 kDa and pI 6.1 was observed in the HCI-treated, cold-treated, and diapause eggs, respectively. Spot 4 was undetectable in unfertilized eggs and non-diapause eggs at two days after oviposition, suggesting that this protein may be associated with the entrance to diapause. A protein, spot 11, with an approximate molecular weight of 21 kDa and pI of 61 was detected in the unfertilized, HCl-treated, and cold-treated eggs, respectively, after oviposition by normal moths. In diapausing eggs, a protein corresponding to spot 11 was observed in 3-, 5-, and 30-day-old eggs, while the protein was not detected one-day-old eggs. The protein corresponding to spot 11 was not detected in unfertilized and non-diapause eggs obtained from subesophabeal ganglion (SG)-extirpated moths either. Spot 11 was also considered to be a diapause specific protein, which occurred at only early embryonic stage under the control of diapause-downregulated gene.

Biological Characteristics of Tetrastichus sp. reared on Artificial Host (인공숙주에서 증식된 Tetrastichus sp.의 생물학적 특성)

  • 이장훈;이기상;이해풍
    • Korean journal of applied entomology
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    • v.41 no.2
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    • pp.99-105
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    • 2002
  • A gregarious pupal endoparasitoid Tetrastichsus sp. (Hymenoptera: Eulophidae) was reared in vitro from oviposition to adult emergence on an artificial host. The host pupal case was made using 0.02 mm-thick polypropylene film, and was filled with a diet consisting of powders of Antheraea pernyi pupa, chicken yolk, infant formula, royal jelly, and Neisenheimer's salt solution. Female parasitoids reared in the artificial host produced smaller sized progeny than those reared in in vivo, but the adults reproduced fertile offsprings. Furthermore in vitro second-generation (G$_2$) females showed more improved biological characteristics, compared with their parents. The fecundity (mean no. adult progeny), oviposition period (days), and longevity (days) of G$_2$ female were evaluated as 45.7, 7.8, and 13.8, respectively Female biased sex ratio was obtained with 76.9% female progeny. The results demonstrated that Tetrastichus sp. is a promising parasitoid for in vitro mass production.

Studies of radiosensitivity (6) Radiosensitivity of insect pests (방사선 감수성에 관한 연구 (6) 해충의 방사선감수성)

  • Bai D. H.
    • Korean journal of applied entomology
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    • v.4
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    • pp.67-74
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    • 1965
  • The work on the 'Studies of radiosensitivity' in Korea has been initiated since 1959 by the author at various institutions in home and foreign countries, and more than 20000 of plant materials in 73 varieties and 41 kinds are treated under varied conditions for the studies of radiosensitivity in plants. However, a study of the susceptibility to radiation in insect pests as well as their biological effects has not been previously reported in this country. During the year of 1964 and 1965, near 50000 of insects at the stages of adult, egg, larva and pupa in 14 different kinds are irradiated under acute X and gamma rays to investigate the behavior of growth and lethality after irradiation, and thrir general tolerances to radiations are compared by the kind of insects, stage of growth, radiation sources and exposured dosages. Through the experiments, it is shown that the lethality in most of insects are high as several kilo roentgens above and no significant effects on pupation. emergence, and oviposition in the treated generation at the dose of 3 Kr. below, but in the following generation , the rice stem borer for instance, no oviposition or decreased laying is observed from the dosages at 3 Kr. to 1 Kr., and the hatching was possible from 1.5 Kr. below of irradiated larvae although laying and hatching are seemed in normal. In general, the lethal dose $50\%$ of tested infect materials at the larval stage can he classified some what 60-80 Kr. for Pine caterpillar, Fall webworm, Camphor silk moth and their relatives, at 40-60 Kr. for Gypsy moth, Monley prominent and some relatives and at 20-30 Kr. for House fly, Rice weevil, Pine sawfly etc. Plant parasitic nematodes such as Hirschmannia and Paratylenchus shown very high resistance to radiation and the LD-50 is observed from 100 Kr. or above. A concept to evaluate the radiosensitivity in insects by taxological family line as a practical measure is not answerable yet, but it ran he solved within the near future through the continuing experiments.

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Comparative Toxicities of Selected Acaricides against the Twospotted Spider Mite(Tetranychus urticae Koch) to Establish the Screeing System for New Acaricidal Chemical Compounds (스크리닝체제 확립을 위한 점박이응애에 대한 몇가지 살비제의 약효 비교)

  • 조점래;최용호;박노중;조광연
    • Korean journal of applied entomology
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    • v.32 no.2
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    • pp.123-128
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    • 1993
  • The comparative toxicities of selected acaricides against the twospotted spider mite, Tetranychus urticae, were investigated. The ovicidal and adulticidal activities of selected acaricides were examined under different developmental stages. Fenpyroximate showed high activity throughout all developmental stages of mites. The oviposition inhibition effect of fenpyroximate was more highly effective than that of cyhexatin. At 100 ppm concentration, the effect of fenpyroximate on the residual oviposition inhibition was persistant during 25 days with 85% level, while the effect of cyhexatin gradually decreased, and then decreased to 40% at 25 days after treatment. Fenpyroximate at 100 ppm showed 100% knockdown activity within 3 hour while cyhexatin showed only 91% knockdown activity within 24 hours after treatment. Most of selected acaricides had no systemic activity, but metasystox at 800 ppm had 100% of the systemic activity at 24 hours after treatment. For the influence of temperature on the activity, fenpyroximate showed stable activity and no temperature-dependent in comparison with other selected adaricides.

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Development of Artificial Diets for Green Lacewing, Chrysopa pallens (Rambur), by Addition of Natural Products (천연첨가물을 이용한 칠성풀잠자리붙이 인공사료 개발)

  • 최만영;이건휘;백채훈;이종진
    • Korean journal of applied entomology
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    • v.39 no.2
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    • pp.99-103
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    • 2000
  • The green lacewing, Chrysopa pallens (Rambur), was reared on artificial diets supplementedwith natural products such as lyophilized beef liver, silk worm pupae powder and drone honey beepowder. The performance of the green lacewing was improved siginificantly on only the diet to whichadded 1 % of silk worm pupae powder (wt/v). Larval developement was completed in 15.6 f 0.99 days,cocoon weight was 16.4f2.94 mg, and suvival to adult was 89.3% at 27$^{\circ}$C. And another diet made bymixing 4 part of lyophilized beef liver powder, 4 part of lyophilized beef powder, 3 part of lyophilizedchicken egg, 4 part of sucrose, and 50 mg each of vitamin C and Vanderzant's vitamin B mixture waspromising. Larval development of the green lacewing on this diet was completed in 12.7 f 1.45 days at27"C, pupal weight was 18.1 f 2.24mg, suvival to adult was loo%, and 633f70.4 eggs were laid in 20days after beginning of oviposition.ginning of oviposition.

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