• Journal of Life Science
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• v.18 no.12
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• pp.1728-1732
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• 2008

This study was performed to investigate the bionomical characteristics of Luciola lateralis in Korea. Imago's longevity of female was $17.5{\pm}0.7$ and male was $20.6{\pm}1.0$ days at $23^{\circ}C$, R.H. 80%, and significant difference was not occurred in breeding density. Pre-oviposition period was a pair $2.8{\pm}1.5$, two pairs $2.5{\pm}1.5$, three pairs $1.7{\pm}0.7$, four pairs $1.3{\pm}0.5$ days and pre-oviposition period was shorten in higher breeding density. The mean of laying eggs was $248.9{\pm}80.7$, was not related breeding density. Daily oviposition rate was 1st day 20.8%, 2nd 17.3%, 3rd 14.3%, 4th 12.7%, 5th 7.0%, the rate was highest in 1st day and gradually reduced. Egg period was $21.8{\pm}0.7$ days and hatchability was $95.5{\pm}4.8%$. Larval instar was identified the 9th instar, the evidence was able to its skin and marking pattern. Larval period of each instar was 1st $1.0{\pm}0.1$, 2nd $3.3{\pm}0.2$, 3rd $10.2{\pm}1.0$, 4th $6.8{\pm}0.5$, 5th $6.9{\pm}2.0$, 6th $15.4{\pm}4.1$, 7th $18.3{\pm}5.9$, 8th $25.8{\pm}8.7$, 9th $31.2{\pm}13.2$ days. Matured 9th larva was made of cocoon during $2.8{\pm}0.8$ days and pre-pupal, pupal period was $4.6{\pm}0.9$, $5.6{\pm}0.7$ days. Imago was made hard hind wing during $3.8{\pm}0.4$ days in cocoon and come out.

• Korean journal of applied entomology
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• v.25 no.3 s.68
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• pp.139-149
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• 1986

These experiments were performed to investigate the effects of sublethal doses of fungicides (validamycin A 3 Sp and neoasozin 6.5 Lq) and insecticides (diazinon 34Ec and decamethrin 1Ec) on the possible ways to the resurgence of brown planthoppers (BPH) (Nilaparvata lugens $St{\aa}l$). The possible factors tested in this experiment were fecundity of BPH, longevity, egg-hatchability, amount of honeydew excreted, population build-up following the pesticide treatments in the next generation, and hopperburn rate of potted rice plants. Among the insecticides tested, the applications of diazinon and decamethrin in rice fields may induce the BPH resurgence and accelerate the hopperburn of rice plants through stimulating the fecundity, increasing the adult longevity, promoting the feeding activity and causing the positve population build-up of the BPH

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.263-270
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• 2013

The vent sexing and the auto-sexing by using sex-linked traits are general sexing methods of day-old chicks. Currently, the feather sexing which is based on the differences in the feather characteristics at hatching is the representative sexing method of chicken, because the late-feathering is sex-linked trait. The feather sexing can be used if the breed has dominant feathering gene (K) in maternal and recessive gene ($k^+$) in paternal. Therefore it is necessary to identify the association of feathering genes and quantitative traits in chickens. In this study, we investigated the influence of the rate of feathering on productive traits in Korean Native Chicken. In results, there was no significant difference between early-feathering chickens and late-feathering chickens in reproductive performance such as fertility and hatchability. Livability, body weights, egg production, egg weight and egg quality also did not significantly differ between early- and late-feathering chickens. Age at first egg was the only trait of those tested in which significant difference was observed. The early-feathering chickens laid eggs 3 days earlier than late-feathering chicken. As a result, there is no influence of feathering phenotypes on productive performance in Korean Native Chickens. Consequentially, establishing the feather sexing strain is available using the Korean Native Chicken breed without considering of the effect of feathering genes on productive traits.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.325-330
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• 2005

This study was conducted to determine the effect of temperatures on the egg and nymphal development, adult longevity and oviposition of bean bug, Riptortus clavatus Thunberg, using Saealkong seed as food sources in fibrous nylon-tube at four different temperatures (20, 24, 28 and $32^{\circ}C$). Hatchability showed the highest value of 100% at $28^{\circ}C$ and decreased with increasing temperature. Egg duration ranged from 7 days at $32^{\circ}$ to 16.7 days at $20^{\circ}C$. Instar duration was longer with increasing instar stage. Nymphal duration was 38 days at $20^{\circ}C$, 30 days at $24^{\circ}C$, 23 days at $28^{\circ}C$, and 18 days at $32^{\circ}C$ Emergence rates to adult were 16, 41, 72 and 68% at 20, 24, 28 and $32^{\circ}C$, respectively. Female adult longelity ranged from a minimum 20 days at $20^{\circ}C$ to a maximum 63 days at $28^{\circ}C$, while the longevity of male ranged from 19 days at $20^{\circ}C$ to 60 days at $28^{\circ}C$. Preoviposition duration was shorter with increasing temperature and ranged from 11 days at $20^{\circ}C$ to 5 days at $32^{\circ}C$. Total number of eggs laid per female ranged from a minimum 21 eggs at $20^{\circ}C$ to a maximum 67 eggs at $28^{\circ}C$. Consequently, the estimated lower threshold tempeatures of each developmental stage were $10.3^{\circ}C$ for egg, and 9.3, 12.7, 10.0, 11.0 and 8.7 for the 1st, 2nd, 3rd, 4th and 5th instar, respectively.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.293-298
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• 2005

The embryonic and postembryonic developments of Pierodorus hybneri Linnaeus were observed in 5 different rearing cages such as A (Cylindrical, 10 cm in diameter, height of 4 cm), B (Cylindrical, 14.5 cm in diameter, height of 2.8 cm), C (Rectangle, 6.5 by 6.5 cm in $length{\times}breadth$, height of 10 cm), D (Cylindrical, 9 cm in bottom diameter, 11.5 cm in upper diameter, height of 10.8 cm) and E (Cylindrical, 15 cm in diameter, height of 7.5 cm) containing soybean and peanut seeds as feeding food, and sponge-water container under laboratory condition of $24^{\circ}C$ and 16L:8D. Egg duration was 6 days regardless of rearing cages. Hatchability ranged from 63 to 80% with the highest in B (14.5 cm in diameter, 2.8 cm in height) rearing cage. Instar duration was longer from 5 days in 1st instar to about 11 days in 5th instar. Nymphal duration showed 35 to 36 days with'3ut significant difference in rearing cages. Percent emergence was in range from 65 to 82% with the highest in B rearing cage. Adult longevity was 35 to 83 days for male, and 32 to 79 days for female, and was the longest in B rearing cage. Total number of eggs laid by female adult was in range from 38 to 86 with significant difference in rearing cages, and was the most in B rearing cage. Accordingly, the reproductive rate of P. hybneri for 1 generation was within 17 to 56 times, and was the highest in B rearing cage. Therefore, it could be concluded that B cage is most suitable for stable rearing of P. hybneri under laboratory condition.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.171-178
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• 1998

This study was conducted to investigate the effect of temperature on the development of amushroom-infesting sciarid fly, Bradysia sp. (Diptera: Sciaridae). Egg period was 12.1, 7.0, 4.4, 3.4, and3.2 days, larval period was 38.3, 26.5, 13.4, 13.2, 12.7 days and pupal period was 10.4, 7.1, 4.4, 3.3, 3.2days, and total development period from egg to adult emergence was 60.8,40.6, 22.2, 19.9, and 19.1 daysat 10, 15, 20,25, 28"C, respectively. Development threshold temperature (DT) and effective accumulativetemperatures (ET) were 3.8"C, 74.8DD in eggs, 1.2"C, 321.8DD in larva, and 3.1$^{\circ}$C, 76.5DD in pupa,respectively. The number of eggs laid per female was 107.9, 129.7, 131.8, 86.9, and 82.7 at respectivetemperatures. Preoviposition period was 6.6, 4.4, 2.2, 1.3, 1.8 days, oviposition period 1.5, 1.5, 1.1, 1.1,1.1 days, postoviposition period 2.0, 1.1, 0.9, 0.6, and 0.3 days at th'e temperature of 10, 15, 20, 25 and 28"C, respectively. The longevity of male and female at the temperature was 13.3, 7.8, 5.9,4.1, 3.4 days and10.4, 7.0, 4.2, 3.0, 3.3days, respectively. The optimum temperature for hatchability was estimated to the20$^{\circ}$C and adult emergence was highest at 20$^{\circ}$C. Pupation rate was 50.7, 68.4, 84.3, 86.5, 45.4% at 10, 15,20, 25, and 28"C, respectively. at 10, 15,20, 25, and 28"C, respectively.tively.

• Journal of Sericultural and Entomological Science
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• v.49 no.1
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• pp.14-17
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• 2007

A new silkworm variety Golden silk for spring rearing season is $F_1$ hybrid between Jam311, a Japanese race bred from introduction breeding and Jam312, a Chinese race from introduction breeding. In the local adaptability test performed at 8 local areas in spring of 2006, "Golden silk" was showed 7 percent higher in hatchability than authorized silk-worm races laval. "Golden silk" was receded higher 1.7 percent, 2.2 percent in pupation rate, best cocoon rate respectively than Chunsujam. The larval period shortened for 1.12 day even though low record to the several items including productivity than Chunsujam. "Golden silk" was showed 1,031 m, 2.97 denier in length of cocoon filament, weight of cocoon filament respectively. The concentration of Deoxynojirimycin(DNJ) was measured 4.34 mg in "Golden silk", high then to "Chunsujam"(3.81 mg). In the Paecilomyces tenuipes production ability test, the pupal weight of "Golden silk" was 1.20g.

• Journal of Sericultural and Entomological Science
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• v.52 no.2
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• pp.110-116
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• 2014

Recently the number of the butterflies, Mellicta ambigua, had been decreasing rapidly, and already disappeared at many habitat. In this studies, we investigated ecological environment of Mellicta ambigua for preparing of primary research data recovering habitat, and studied on bionomical characteristics. Two different habitat, Jindo and Inje, were selected for investigation of ecological environment. We investigated four times during 3-month, from June to August in 2012. In Jindo, we observed more than 100 butterflies and a lot of host plants, Melampyrum roseum var. japonicum. But only 5 butterflies and only a few host plants, Veronicastrum sibiricum were observed in Inje. We could not observe the eggs, the larva and pupa on the host plants at all. For finding of bionomical characteritics, we reared butterflies at natural conditions. Collected 3-female butterflies from Jindo laid 465 eggs on the leaves of 3-host plants, Veronicastrum sibiricum. 120 ~ 186 eggs per each female were laid in the shape of cluster. An egg was globular shape, 0.6 mm diameter and 0.7 mm height. The egg periods were $9.96{\pm}0.4days$ after ovipositioning, and the hatchability was 95.% at natural condition. The larval periods were $4.1{\pm}0.6days$ (1st instar), $2.1{\pm}1.0days$ (2nd), $8.1{\pm}0.7days$ (3rd), $239.2{\pm}10.9days$ (4th), $12.3{\pm}1.3days$ (5th), $17.1{\pm}1.1days$ (6th), $10.5{\pm}1.0days$ (7th) each other. The larva of 4th instar overwintered in the nest that had been made into the leaf of host plant with secreted thread as a group until early March next year. In the early March next year, overwintered larva went around their nest in search of host plants, and went to other host plants, Veronica persica and Plantago asiatica, sometimes. The overwintered larva of Mellicta ambigua could grow up on two other host plants normally. In the following experiment, the butterflies of Mellicta ambigua laid eggs on the leaves of Plantago asiatica, but the 1st instar larva from eggs died all. The headwidth of each developmental larval stage were $0.28{\pm}0.02mm$ (1st), $0.45{\pm}0.02mm$ (2nd), $0.58{\pm}0.02mm$ (3rd), $0.75{\pm}0.03mm$ (4th), $0.89{\pm}0.05mm$ (5th), $1.23{\pm}0.06mm$ (6th), $2.13{\pm}0.11mm$ (7th). The pupal ratio was 92.0%. The pupal period were $9.1{\pm}1.6days$, and the emergence rate was 88.6%. As a result we determined that Mellicta ambigua can rear at natural conditions. But indoor-rearing is considered to be difficult and not useful industrially, because they have long term larval stage and only one life cycle per an year.