• Korean journal of applied entomology
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• v.58 no.4
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• pp.347-354
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• 2019

Temperature-dependent traits of Laodelphax striatellus, rice stripe virus vector, were investigated at 10 constant temperatures (12.5, 15.0, 17.5, 20.0, 22.5, 25.0, 27.5, 30.0, 32.5, and 35.0 ± 1℃) under a fixed photoperiod (14/10-hr light/dark cycle). Unit functions for the oviposition model were estimated and implemented into a population dynamics model using DYMEX. The longevity of L. striatellus adults decreased with increasing temperature (56.0 days at 15.0℃ and 17.7 days at 35.0℃). The highest total fecundity (515.9 eggs/female) was observed at 22.5℃, while the lowest (18.6 eggs/female) was observed at 35.0℃. Adult developmental rates, temperature-dependent fecundity, age-specific mortality rates, and age-specific cumulative oviposition rates were estimated. All unit equations described adult performances of L. striatellus accurately (r² =0.94~0.97). After inoculating adults, the constructed model was tested under pot and field conditions using the rice-plant hopper system. The model output and observed data were similar up to 30 days after inoculation; however, there were large discrepancies between observed and estimated population density after 30 days, especially for 1^st and 2^nd instar nymph densities. Model estimates were one or two nymphal stages faster than was observed. Further refinement of the model created in this study could provide realistic forecasting of this important rice pest.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.225-229
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• 2014

Seasonal changes in the firefly (Luciola lateralis) were studied in the laboratory to understand biological characteristics. Fecundity varies with seasons; these were measures at $162.0{\pm}8.67$ in the winter, $226.9{\pm}15.84$ in the spring and $166.6{\pm}9.3$ in the summer. Seasonal change also influenced oviposition period ($6.9{\pm}0.59$ days in the winter, $16.1{\pm}1.10$ days in the spring and $8.2{\pm}0.61$ days in the summer). The firefly oviposited every $2.5{\pm}0.22$ days in the winter, $3.9{\pm}0.25$ days in the spring, and $2.3{\pm}0.14$ days in the summer. Oviposition occurred 3 times in the winter, and 4 times in the spring and summer. The number of eggs per cycle was $52.2{\pm}4.56$ and $55.9{\pm}4.38$ in winter and spring, respectively, and was lower in the summer ($42.2{\pm}3.76$). Egg period significantly differed among seasons. The life span of the firefly was $17.9{\pm}0.14$ days in the winter, $19.7{\pm}0.25$ days in the spring and $16.5{\pm}0.43$ days in the summer.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.162-168
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• 2010

This study attempted to clarify the difference in eggshell pigmentation between blue-shelled ducks (BSD) and whiteshelled ducks (WSD). The eggshell pigmentation deposition process is discussed. Ultraviolet spectro-photometer and HPLC were used to determine the biliverdin concentration in the shell gland, uterus liquid and eggshell at 6, 12, 18, 20, 23.5 h post-oviposition. The biliverdin concentration in the eggshell and uterus fluid showed significant differences between BSD and WSD, but not in the shell gland. The heme oxygenase activity in the shell gland of both kinds of ducks remained mostly constant during the ovulatory cycle with no variation. The assay of exogenous biliverdin injection into the shell gland antrum in the WSD indicated that exogenous biliverdin could be deposited continuously into the eggshell until the source was exhausted. A layer-by-layer dissolution assay was used to examine the eggshell pigment deposition process. The biliverdin concentration in the first to sixth layers of the eggshell in the BSD was significantly higher than that in the white-shelled counterpart. The blue pigment concentration increased persistently from the 6th layer to the $1^{st}$ layer. The BSD eggshells did not accumulate a large quantity of biliverdin in the most external layer. They tended to increase the deposition layer by layer. Our results demonstrated that different BSD and WSD eggshell colors were influenced by the amount of biliverdin in the uterus fluid and not determined by the amount of biliverdin in the shell gland. This implies the existence of a mechanism that controls biliverdin transportation from the shell gland into the uterus fluid, thereby playing a key role in regulating duck eggshell color.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.193-197
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• 2000

Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

• Korean journal of applied entomology
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• v.41 no.1
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• pp.43-47
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• 2002

This study was carried out to investigate the ecological characteristics of Protaetia orientalis submarmorea (Burmeister). The emergence period of adults is appeared from April to October, and most abundant in July∼August, once a year in the field. Hibernation took place mostly in larval stage, but some in adult stage, and were generally found in the decayed rice straws and in the soil covered with compost or similar materials with average depth of 17.6 cm The developmental characteristics in the insectary (28$^{\circ}C$, 70% RH, 16L: 8D) was investigated: the average number of eggs laid per female is 82.8, egg period 8.4 days, 1st instars of larva 10.6, 2nd 18.7, 3rd 38.1, and pupal period 35.5 days. Longevity of the adult was 135.2 days In the female and 121. 7days in the male.

• Korean journal of applied entomology
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• v.14 no.3 s.24
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• pp.163-166
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• 1975

This experiment was performed to investigate the X-ray sensitivities at the various stages of life cycle and to determine the sterillizing dose of stable fly, Stomoxys calcitrans(L). A dose of 300 rad caused about $50\%$ mortality in 2-hour-old eggs as measured by egg hatch, and $100\%$ mortality was obtained with a does of 1 Krad. Sub-lethal dose $(LD_{50})$ for the pupal mortality after irradiation of 3-5days old pupae were 11.5 Krad and the mortality was decreased with increasing pupal age at irradition. A significant reduction of egg hatch by $1.5\%$ was observed when treated males with 3 Krad at pupal stage were mated to untreated virgin femleas. On the other hand, $100\%$ sterility in females was resulted by 2 Krad irradiation and oviposition was completely inhibited with 3 Krad. Thus, both sexes of stable fly could be sterilized with a dose of 4 Krad irradiated to 3-5 days old pupae.

• Korean journal of applied entomology
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• v.34 no.4
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• pp.300-307
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• 1995

This study was carried out to investigate the life cycle of Cephonodes hylas (Linne), that is damaging to Gardenia jasminoides Ellis in the seedbed at Namhae during 1984 and 1985. Results are summarized as follows. The eggs were laid in mass on the leaf surface of the host plants. The oviposition period lasts for 26 days after late-May. The average number of eggs and average hatching rate were 20.36 and 97.61% , respectively. It takes 14-16 days until hatching. The egg shape was oval which its size was 1.01 mm in diameter and 1.48 mm in length. The body length of each larval instar from the 1st to the 5th were $3.52\pm$1.01, $6.46\pm$0.45, $13.19\pm$4.27, $24.08\pm$2.22 and $43.71\pm$5.62 mm, respectively. The average weight of each larval instar were $13.34\pm$2.41, $29.83\pm$6.88, $76.64\pm$31.31, $292.09\pm$107.70 and 2,$144.84\pm$760.70 mm, respectively. The larval period was observed from July to October, and total duration of larval stage was 116 days in which duration of each larval instar from the 1st to the 5th were 12, 36, 32, 16 and 20 days, respectively. During larval stage, a larvae feed on 17~18 seedlings. The 5th instar larvae built its place in soil for overwinter and became pupa. The body length of pupa was 33.6 mm and average weight was 2,032 mg Adult was emerged from overwintened pupa from mid through late-May in the followings year. The sex ratio of female was 42.82% and the color ratio of brown was 89.93%.

• Korean journal of applied entomology
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• v.52 no.2
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• pp.93-100
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• 2013

In this study, the distribution of Cantao ocellatus in Korea occurred at Jindo, Tongyoung, Gwangju and Taean including Jejudo in 2012 and was coincidentally in accordance with the distribution of Mallotus japonicus as a host plant. The adult emerges in M. japonicus occur from late June to early July and can be observed until the end of October. The investigation of the female and male was measured, developmental characteristics, host plant and oviposition preference under the conditions of temperature $25^{\circ}C({\pm}2)$, humidity 65%(${\pm}2$), day length 16L:8D, by indoor breeding. For females and males respectively, average body lengths were 26.20 mm and 23.88 mm, body widths 11.35 mm and 10.57 mm, head widths 3.84 mm and 3.64 mm, probosics lengths 7.90 mm and 7.27 mm, antennal lengths 9.87 mm and 9.69 mm, anterior leg lengths 12.50 mm and 12.27 mm, intermediate leg lengths 14.61 mm and 13.12 mm, posterior leg lengths 16.90 mm and 16.53 mm, and fresh weights 0.46 g and 0.31 g. It was seen that two kinds of C. ocellatus had prickles at the end of the pronotum which had developed in the fifth instars. The female is distinguished from the male by the reproductive organ and the spotted pattern on the abdominal segment. The preference of drinks was fruit, leafstalk, midrib, and branch in Mallotus japonicus (Thunb.) Muell. Arg., Mallotus japonicus 'Variegatus', Ricinus communis L., Lonicera japonicus var. repens (Siebold) Rehder, Citrus sinensis (L.) Osbeck and Zelkova serrata (Thunb.) Makino.

• The Korean Journal of Ecology
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• v.23 no.1
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• pp.65-70
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• 2000

Field collections were made from six gypsy moth (Lymantria dispar L.) Populations in Kyonggy and Cheju areas during the period 1987∼1997. Characteristics of gypsy moth populations at different phases were examined in terms of egg mass density, relative larval density, plant damage, and fecundity. Males captured in pheromone trap were recorded, and we examined if there was a relationship between numbers captured and the population density during the following generation. Egg mass density was closely related with larval density, and furthermore these densities were correlated with the level of plant damage, indicating that larval dispersion was limited in oviposition areas. The gypsy moth population cycle was short in Korea with the period from population development to innocuous level usually lasting 2∼3 years. Male caught by pheromone trap (mean number of males caught per trap per day in peak emergence period) was positively correlated with egg mass densities in the following season (r²=0.93). A low fecundity was detected from outbreak populations which accompanied defoliation. Fecundity of gypsy moth ranged from 538 to 601 at other phases.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.153-163
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• 2020

This study was conducted to evaluate the fitness of Tetranychus kanzawai Kishida on different host plants: young and old leaves of the mandarin orange 'shiranuhi' ((Citrus unshiu × C. sinensis) × C. reticulata), Japanese violet (Viola japonica Langsd.) and kidney bean (Phaseolus vulgaris L.). The development and oviposition experiments were conducted at constant temperatures (20, 25 and 30℃) and a life table parameters were estimated. T. kanzawai could complete it's development on 'shiranuhi' young leaves, japanese violet and kidney bean, while all died during the immature period on 'shiranuhi' old leaves. The total developmental period of T. kanzawai feeding on 'shiranuhi' young leaves was 17.4, 13.4 and 10.2 days at each temperature, respectively, which was longer than 16.1, 9.5 and 7.0 days of kidney bean. The female longevity of T. kanzawai on young leaves of 'shiranuhi' were 19.1, 15.0 and 12.3 days at each temperature, respectively, and there was no significant difference from 22.1, 14.1 and 10.9 days investigated from kidney bean. The fecundity was 18.1, 23.9 and 17.8 eggs per female, which was less than them of japanese violet and kidney bean at each temperature, respectively. As a result of estimating the life table parameters based on the experimental data, intrinsic rate of increase (r_m) were significantly different from each other, and appeared in the following order: kidney (0.1542, 0.2563 and 0.3251), japanese violet (0.1087, 0.2007 and 0.2673) and 'shiranuhi' young leaves (0.0868, 0.1002 and 0.1217) at each temperature, respectively. Finally, the management strategy against T. kanzawai in citrus orchards was discussed based on the results.