• Korean journal of applied entomology
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• v.52 no.1
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• pp.29-33
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• 2013

The fecundity of summer generation adults of arrowhead scale, Unaspis yanonensis (Kuwana) (Hemiptera: Diaspididae), was examined at constant temperatures. The total fecundity increased up to $29^{\circ}C$ and declined thereafter. Total fecundity reached a maximum of 254.5 eggs (crawlers) per female at $29^{\circ}C$. Females showed periodic oviposition activity but the pattern differed with temperature. Three or more oviposition cycles were occurred at 25 and $29^{\circ}C$. At the other temperatures, the 2nd oviposition cycle was reduced or obscure. And oviposition cycle after the 2nd cycle was not obvious at low or high temperatures. The fecundity of the 1st cycle was significantly different according to temperature, showing higher fecundity at 25 and $29^{\circ}C$. Fecundity after 1st cycle at 13, 17 and $21^{\circ}C$ were lower than at 25 and $29^{\circ}C$. The sex ratios of hatched nymphs in terms of female : male in 13, 17, 25, 29 and $33^{\circ}C$ were 1 : 0.48, 1 : 4.79, 1 : 2.48, 1 : 1.85 and 1 : 0.56, respectively.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.281-286
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• 2014

In grape vineyards, whitish spots in a cloud shape have been often observed on the fruit surface recently. However, the cause of the halo spot symptom was unknown, hindering countermeasures to be properly designed for the control. A small hole in the middle of the formless halo spot remained as a scar formed by oviposition of the thrips. It became later a suberized scab, which is separated from the epidermal cells on the surface either to be retained on or to be detached from it as time proceeds. Such a symptom is distinguished from the feeding damages caused by thrips or true bugs occurring on the grape fruits. With DNA extracted from the egg-shell found in the hole, molecular diagnosis by amplifying an ITS2 region with universal primers and subsequently digesting the PCR product by an restriction enzyme (RsaI) revealed that the egg was laid by Frankliniella occidentalis. In addition, a mitochondrial COI sequence confirmed that the halo spot symptom was formed by its oviposition. This study provides accurate information on the peculiar damage symptom caused by oviposition of F. occidentalis that could be useful in the control strategies for this pest in vineyards.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.133-138
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• 2020

In 2016, the two-spotted cricket was approved as a general food ingredient by the Korean Ministry of Food and Drug Safety. Additionally, the two-spotted crickets have high protein content (60%) and can be reared throughout the year even during the overwintering period. In this study, storage conditions were set in case cricket breeding was not possible due to problems such as breeding space and labor costs, and selection oviposition mats to determine high fecundity rates and low cannibalism rates for the eggs were investigated. The oviposition mat was mostly composed of soil (p < 0.05). Less than 62 crickets per 10 litters were found to be best suited for 1 day of spawning, based on the cannibalism rate of the eggs during the egg laying period. The results from the hatched eggs indicated that the hatching extended 12 to 14 days, and the best hatching rate was approximately 85% when stored at low temperatures(16℃) for 10 days. An efficient production proposed method that established the best oviposition mat and egg storage method for the cricket.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.133-138
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• 2003

To establish the successive rearing of red-striped golden stink bug, Poecilocoris lewisi Distant, developmental characteristics, host plant and oviposition preference were investigated. Raw peanuts were supplied to the insect as a substitute food at 25$\pm$$1^{\circ}C$, 60$\pm$5% R.H. and under 16Lㆍ8D photo regimen. Total developmental period was 48 days: 8.2$\pm$0.4, 5.4$\pm$0.2, 8. $\pm$0.5, 6.4$\pm$0.4, 7.4$\pm$0.3 and 12.6$\pm$0.8 days for egg, first though fifth instar, respectively. The instar survival rate was 57.1% and the sex ratio was estimated to be 53 : 47 (male : female). Adult longevity was on the average 30.8 in male and 35.4 days in female, respectively. Egg of P. lewisi was globular ($\phi$1.8-1.9mm) with milky white in color The number of eggs oviposited per clutch was mostly 14. Pre-oviposition period was 25.8 days and mean frequencies of oviposition were 4.4. Female preferred to oviposit on the host plant when available, but oviposited on the artificial leaf successively when the host is not around. On the other hand P. lewisi preferred to suck the nectar of stem or fruit of Phellodendron amurense Ruprecht, Zanthoxylum schinifolium Siebold et zuccarini, Cornus officinalis Siebold et zuccarini and Cornus controversa Hemsley among the 18 plant species tested.

• Journal of Aquaculture
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• v.4 no.1
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• pp.31-66
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• 1991

This paper deals with the reproductive ecology e.g., number of the pre-spawning moults, morphological characteristics of the pre-spawning moult the common moult, daily ration druing a molting cycle mating behavior, structures of spermatozoa and spermatophore, structure of vas deferens, mechanisms of the oviposition and brooding into the egg-chambers, a suitable time for the artificial mating and fertilization, time sequence of the oviposition and brooding into egg-chambers from the copulation, responses to temperature and chlorinity on the egg development and hatching, effect of temperatures on duration of egg development, physical mechanism of the egg hatching, to make an attempt for the artificial spawning and brooding to establish a suitable system of the artificial seedling-production for the aquaculture. 1. Females molted commonly $8{\~}10$ times at an interval of $17{\~}18$ days at $28^{\circ}C,\;3.26\~4.35\%_{\circ}$ while the prespawning moltings were $4{\~}5$ times at an interval of $13{\~}14$ days. The suitable state for artificial copulation was within 14 hours elapsed from the prespawning moltings (most suitable state was within 8 hours). Males discharged a gelatinous spermatophore and placed it on the females sternum during copulation. Oviposition was seen $6{\~}17$ hours after copulation. External fertilization was considered to take place at oviposition. Fertilized eggs held in egg-chambers forming between pleopods were about $5000{\~}6000$ in females those sizes about 6.5 cm in body length. 2. Eggs immediately after oviposition were elliptic shape, measuring $0.58{\times}0.48$ mm up to hatching. Their sizes increased with egg development and finally reached $0.85{\times}0.54$ mm up to hatching. The relationship between the long axis of the egg(Y in U) and days elapsed(X) was expressed as Y= 5.60194 + 0.007358X. The eggs performed superficial cleavage and their cleavage furrows became visible at the 4-daughter-nucleus stage. The eggs showed normal development up to hatching at water temperature range of $22{\~}30^{\circ}C$ (optimum temperature : $26{\~}28^{\circ}C$) and at chlorinity range of $0.00\~6.64\%_{\circ}$ (optimun chlorinity : $2.21{\%}_{\circ}$). The relationship between incubation period (Y in days) and water temperature(X in $^{\circ}C$) could be expressed as Y= 50.803-1.3555X. The eggs hatched $12{\~}13$ days after oviposition at $28.0{\~}28.6^{\circ}C$ 3. The pre-spawning moltings were appreciably different in the morphologic structure from those of common moltings. Breeding setae and dresses were formed on the thoracic regions, abdominal epimerae and the bases of the first to fourth pleopods in order to prepare and support oviposition, transfering and supporting eggs in egg-chambers up to hatching. These supplementary breeding organs were observed only at reproductive seasons.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.387-394
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• 2017

Temperature-dependent oviposition model and life table parameters of Paromius exiguus (Distant), the causal agent of 'pecky' rice grain were examined at eight constant temperatures (17.5, 20, 22.5, 25, 27.5, 30, 32.5, and $35{\pm}^{\circ}C$) and a photoperiod of 14:10 (L:D) h. Unit functions of the oviposition model were developed and life table parameters were estimated. The longevity of P. exiguus adults decreased with increasing temperature (123.8 days at $17.5^{\circ}C$ and 23.6 days at $32.5^{\circ}C$). Total fecundity was highest at $30^{\circ}C$ (585.2 eggs/female) and lowest at $17.5^{\circ}C$ (21.5 eggs/female). In order to develop a temperature-dependent oviposition model, adult aging-rate, temperature-dependent fecundity, age-specific survival rate, and age-specific cumulative oviposition rate equations were estimated. All unit equations ($r^2=0.92{\sim}0.98$) except for the temperature-dependent fecundity equation ($r^2=0.83{\sim}0.85$), described oviposition characteristics of P. exiguus adequately. Life table parameters of P. exiguus were estimated at various constant temperatures. Net reproduction rate ($R_0$) was highest at $30^{\circ}C$ (118.21). Mean generation time (T) was shortest at $32.5^{\circ}C$ (32.99 days) and doubling time (Dt) was shortest at $30^{\circ}C$ (5.69 days). The highest values of intrinsic rate of increase ($r_m$) and finite rate of increase (${\lambda}$) were 0.122 and 1.129 at $30^{\circ}C$, respectively.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.175-179
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• 2012

The present study is to develop the rearing method of Gryllotalpa orientalis. In total 429 of G. orientalis were collected from the field rearing cage ($25m^2$) in 2012. Its sex ratio was 1: 1.15(Female : Male). Survival rate of the mole crickets was 94.4~86.1% with the artificial diets formulated for the present study. Successful oviposition rate was 20, 20 and 80% for one, two and three pairs of adult crickets, respectively, from the indoor rearing. The mean number of hatchlings was $11.8{\pm}21.7$, $15.7{\pm}26.4$ and $25.8{\pm}38.8$, and the mean number of dead hatchlings 1.2, 1.7 and 1.2. The mortality of nymphs on horticultural soil and clay sand mixed with ocher was 18.3 and 10.0%, respectively. The mortality of nymphs in circular and rectangular cages was, respectively, 60 and 40%.

• International Journal of Industrial Entomology and Biomaterials
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• v.5 no.1
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• pp.127-129
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• 2002

Lepidoscelio viatrix is a potential biocontrol agent of the eggs of wingless grasshopper, Neorthacris acuticeps nilgerensis, in mulberry plantation in natural conditions. The present investigation was undertaken to understand the attachment of the parasite to the hopper under scanning electron microscope and the oviposition behavior of the parasite. The results reveal that the parasite grips firmly to the lateral and dorsal surfaces of the female grasshopper with its mandibles implanted in the intersegmental membranes of the abdominal segments. During oviposition, L. viatrix initially turn around the egg pod and protrude its ovipositor and insert into the eggs. It lays eggs inside the eggs of grasshopper by an up and down movement of the ovipositor, Further, field observations indicated a drastic fall in the incidence of the grasshopper population on mulberry, with the increased parasitization of L. viatrix.

• Proceedings of the Zoological Society Korea Conference
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• 1998.04a
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• pp.42.1-42
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• 1998

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.122.1-122
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• 1997

No Abstract, See Full Text