• Korean journal of applied entomology
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• v.58 no.3
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• pp.197-202
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• 2019

Jujube tree farms need effective methods of pest control to reduce damage caused by mirid bugs. In this study, we measured the density of mirid bug populations in jujube trees and tested the efficacy of various insecticides. We observed seasonal density patterns, where nymphs were observed from early May to the middle of July; and adults were observed from the end of May to the middle or end of July. Furthermore, we measured the density of two types of mirid bug species, Apolygus spinolae and A. lucorum. Among 45 damaged jujube trees, the dominant species of mirid bugs was A. spinolae (89%). We tested 7 types of insecticides to control mirid bug populations, including pyrifluquinazon, deltamethrin, diazinon, dinotefuran, etofenprox, fenitrothion, and bifenthrin, showing over 80% efficacy. Thus, in this study, we showed that using insecticides was effective for controlling mirid bug populations on jujube trees.

• Korean journal of applied entomology
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• v.41 no.1
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• pp.33-41
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• 2002

The mirid bug damages on grapevine were observed not only on young shoot and leaves (decoloration, deforming, and perforation) but also on fruits (black spot, corky scar, and young fruit shattering). Among 159 fields surveyed throughout the country, 113 fields (71%) were damaged, and the damages were relatively severer in the chief producing districts of grape vine, such as Gimpo, Anseong, Naju, Gimcheon, Buyeo, Daejeon, Yesan than other districts where grapevine yards were not concentrated. The severest shoot damages were observed in two grape vine yards of Naju (85%) and Gimpo (65%) in 1999. Three species of virid bugs were recognized on grape vine tree, Apoygus spinolae (Meyer-Dur), Apolygus lucorum (Meyer-Dur), and Orthotylus (Melanotrichus) flavosparsus(Sahlberg). Among them, A. spinolae was dominant species in the number of specimens collected. A. spinolae were collected on 10 host plants including Vitis vinifera L., Prunus armeniaca var. ansu Max., and prunus serrulata var. spontanea(Max.) Wils. and etc., and A. lucorum were collected on 10 species of plants, including Artemisia iwayomogi Kitamura, Artemisia princeps var. orientalis(Pampan) Hara and etc. Both A. spinolae and A. lucorum distributed widely in Korean grapevine yards.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.492-495
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• 1992

Life cycle of the mirid predator, Cyrtorhinus lividipennis, was observed on the constant temper¬ature. Egg periods were 14.43, 9.33 and 6.94 days at $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively. Nymph periods were 24.3, 14.42, and 11.90 days at $20^{\circ}C$, $25^{\circ}C$ and $30^{\circ}C$, respectively and fe¬male longevity was 11.20, 11.93 and 11.87 days at above temperatures. Relationships between constant temperature and the developmental velocity of egg, nymph and egg-nymph were lin¬ear over temperatures tested. The calculated threshold temperatures of development were $10.7^{\circ}C$ in egg, $9.8^{\circ}C$ in nymph and $10.2^{\circ}C$ in egg-nymph. Total effective day-degrees were 133.9 in egg, 235.8 in nymph and 368.0 in egg-nymph. Number of eggs laid was 26.0 and 22.4 at $24^{\circ}C$ and $30^{\circ}C$, respectively.

• Korean journal of applied entomology
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• v.5_6
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• pp.55-58
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• 1968

본시험은 1966년 필리핀에 있는 국제수도연구소에서 벼멸구의 생태에 관한 시험을 위하여 벼멸구를 대량으로 집단접종사육하여 오딘 중 cage내 갑자기 벼멸구의 밀도가 줄고 장님노린재가 무수히 번식되고 있는 것을 관찰한 후 Hawaii에 있는 Bishop Museum, Dr. ASHLOCK 씨에이 장님노린재에 대한 동정을 의뢰함과 동시에 벼멸구에 대한 포식성을 조사한 결과 벼멸구의 포식식능력은 장님노린재를 산난된 도엽에 접종하였을 때 5일후 포식난율이 $69.1\%$인대 대하여 벼멸구 고충에 대하여서는 접종 1일 후$61.4\%$, 2일 후 $76.2\%$, 3일 후 $91.0\%$ 4일 후 $93.3\%$의 포식률로서 매우 놀라운 포식능력을 보여주었다. 이 장님노린채는 벼멸구뿐만 아니라 다른 멸구류의 밀도를 제압할 수 있기 때문에 단장조건하에서는 벼멸구류의 피해를 미연에 경감시킬 수 있는 유리한 천적이라고 생각되며, 금후 이의 실제적인 이용면에 대한 연구가 기대된다.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.234-242
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• 1995

The functional responses of the female Cyrtorhinus lividipennis on brown planthopper (BPH), Nilaparvata lugens, eggs and their predation behavior were investigated at six temperature conditions; 20, 23, 26, 29, 32, and $35^{\circ}C$. C. lividipennis was found to prefer young BPH eggs, especially 3-day-old eggs the most. The functional responses for female C. lividipennis on BPH eggs fitted the Holling's Type-I true predator-prey Rogers' (1972) model at all temperatures tested except $35^{\circ}C$ at which the negative Th value was produced. With the temperature increased up to 32$^{\circ}C$, the instantaneous attacking rate(a) increased from 0.1923 at $20^{\circ}C$ to 0.5085 at $32^{\circ}C$, while the handling time (Th) was gradually decreased as low as 0.0151 at $32^{\circ}C$. C. lividipenis preferred the BPH eggs laid on the upper part of rice stem when the BPH egg density was high, but there was no significant difference in the preference when the egg density was low. The preference was more obvious in high temperature conditions such as above 29$^{\circ}C$.

• Korean journal of applied entomology
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• v.36 no.4
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• pp.311-316
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• 1997

This study was conducted to evaluate the effect of temperatures on the egg and nymphal development andadult longevity of green mirid bug, Cvrtorhinus lividipennis Reuter. In addition, predation on eggs of brownplanthopper, Nilupurvurcz lugens ~t:l and small brown planthopper, L~orlelphux .striatellus Fallen by C.lividipennis were studied at different temperatures. Hatchability of C. lividipennis was about 96% at 23"C,88% at 26"C, 75% at 29$^{\circ}$C and 64% at 32$^{\circ}$C. Egg duration of C. lividipmnis was 1 1.0 days at 23"C, 10.0 at26"C, 6.7 days at 29$^{\circ}$C and 5.6 days at 32$^{\circ}$C. Nymphal duration of C. 1i1~idiperzni.ws as 13.7 days at 23"C,12.7 days at 26$^{\circ}$C. 10.2 days at 29$^{\circ}$C and 9.1 days at 32$^{\circ}$C regardless of food sources. Nymphaldevelopment was the shortest at 4th instar and the longest at 1st instar irrespective of temperatures and foodsources. Adult longevity of C. livirlipennis was was about 22.0 to 23.5 days at 23$^{\circ}$C. 19.0 to 20.0 days at26"C, 16.0 to 17.0 days at 2Y0C, and 1 1.0 to 12.0 days at 32$^{\circ}$C. There was no significant difference in adultlongevities on food sources. Number of eggs comsumed by adult C. lividipennis were about 56 to 61 and 56to 57,56 to 60 and 47 to 49,43 to 46 and 40 to 42, and 28 to 30 and 26 to 27 at 23'C. 20$^{\circ}$C. 29$^{\circ}$C and 32"C,respectively. Egg consumption by adult C. lividiprrznis was slightly higher at female and on N. lugens eggthan at male and on L. striatellus egg. Dail 2.0 to 3.0 eggs were consumed by adult C. lividipc,nni.s.ail 2.0 to 3.0 eggs were consumed by adult C. lividipc,nni.s.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.409-413
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• 2013

This study was performed to understand whether host-plant feeding had an influence on subsequent prey consumption in the zoophytophagous mirid Nesidiocoris tenuis, which has the potential for biological control of greenhouse whiteflies. Potted plants of paprika and sesame and cotton balls soaked with water were provided to the test insects for 24 h, then, frozen eggs of Ephestia kuehniella were presented to adult mirids for 24 h, and the number of eggs consumed by them was counted. No significant difference in prey consumption was observed between the mirids previously provided with water ($49.2{\pm}30.58$ eggs) or paprika ($55.7{\pm}31.19$ eggs), whereas those previously fed with sesame ate significantly less prey ($24.2{\pm}34.70$ eggs) than the mirids that were provided with paprika or water.

• Korean journal of applied entomology
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• v.35 no.1
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• pp.52-57
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• 1996

This experiment was carried out to evaluate the effect of sublethal doses of BPMC, etofenprox,and buprofezin on N. lugens. and its predator C. lividipennis. Buprofezin was found to be the most toxic to N. lugens and the most safe to C. lividipennis among the three insecticides, based on LD50 values. Selective toxicity index calculated by dividing LDSo value of C. lividipennis by that of N. lugens indicated that buprofezin was very safe to C. lividipennis, showing selective toxicity of 2703.3. Longevity and fecundity of N. lugens treated with LDIU and LDm of buprofezin and BPMC were not significantly different with those of untreated brown planthoppers. However, egg hatchability' of N. lugens was greatly reduced when treated with LDm of buprofezin, having the highest inhibition rate of 17.7%. Hatchability of eggs from insects treated with BPMC was similar to that of control. The oviposited peak of treated hoppers appeared late as compared to the untreated which showed the peak at early part of the ovipositional period. The longevity and fecundity of C. lividipennis treated with BPMC were significantly reduced as compared with the untreated. Etofenprox also induced fecundity reduction when treated with LDlo, and LDm. However, C. lividipennis treated with sublethal doses of buprofezin showed no redution in logevity and fecundity. From these results, it may be said that buprofezin can be used to control brown planthopper without disrupting of C. lividipennis population in the rice field.

• Korean journal of applied entomology
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• v.41 no.1
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• pp.67-73
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• 2002

Studies were conducted to investigate the control effects of several insecticides on Apolygus(=Lygocoris) spinolae(Meyer-Dur) and to develop its management strategies in grapevine yards. Of insecticides which were applied by farmers in commercial grapevine yards, chlorpyrifos, parathion, fenvalerate, and esfenvalerate$.$fenitrothion showed good control effects against A. spinolae. In designed field experiments of fenitrothion and chlorpyrifos for the evaluation of A. spinolae control, both insecticides showed high control efficacy of 94.8 and 91.6%, respectively. The damage of A. spinolae was examined in a grapevine yard, where five different combinations of application timing and number were treated with fenitrothion to assess yield losses (average cluster weight) by A. spinolae. There were no significant differences among average cluster weights of sprayed vines; 466.0 g in sprayed vines on 2 to 3 leaves unfolded stage, 460.7g in sprayed vines on flower separating stage, 465.0 g in sprayed vines each on 2 to 3 leaves unfolded and flowers separating stage, and 487.4 g in sprayed vines each on 2 to 3 leaves unfolded, flowers separating and fruit set stage. Weights of fruit clusters of unsprayed vines was significantly lower than those of sprayed vines. Based on yield and spray cost, chemical control on 2 to 3 leaves unfolded stage produced higher net income than each spray on 2 to 3 leaves unfolded and flower separating stage (i.e., two times of spray), and produced similar net income as each spray on 2 to 3 leaves unfolded, flowers separating and fruit set stage (i.e., three times of spray). Thus, the 2 to 3 leaves unfolded stage was economical spray timing to controlA. spinolae in grapevine yards. Also, management strategies for A. spinolae were discussed.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.91-97
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• 2002

This study was conducted to determine the effects of temperature and food onthe nymphal development and adult longevity of the green virid bug, Cyrtorhinus lividipennis Router. Nymphal period was 13.2 to 13.7 days at 24$^{\circ}C$, 10.4 to 10.9 days at 28$^{\circ}C$, and 9.0 to 9.3 days at 32$^{\circ}C$. Number of eggs predated by nymph was 10.6-14.3 at 24$^{\circ}C$, 7.5-9.2 at 28$^{\circ}C$, and 5.8-7.5 at 32$^{\circ}C$. Amount of predation was highest on BPH, followed by SBPH, WBPH, and GLH. Number of nympal moulting was mostly four times (55-75%) followed by three times (25-45%), regardless of temperature and food. Percent emergence rate was 52-70%, 48-66% and 22-38% at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, showing a tendency to decrease with increasing temperature, and was affected by foods. Adult longevity, when supplied with one food, was 19.8 to 22.5 days at 24$^{\circ}C$, 15.6 to 17.0 days at 28$^{\circ}C$, and 10.3 to 11.7 days at 32$^{\circ}C$. There was no significant difference among foods in terms of adult longevity, but it tended to be slightly longer when provided with four foods than with one food. Number of eggs predated by an adult, when supplied with one food, was 35.7-54.2, 31.6-44.6 and 18.1-28.2 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively. It was highest on BPH, followed by SBPH, WBPH and GLH regardless of temperature. Number of egg Predated by an adult, when supplied with four foods, was 4.0-28.9, 2.9-29.0 and 17-13.6 at 24$^{\circ}C$, 28$^{\circ}C$ and 32$^{\circ}C$, respectively, and was significantly different among foods supplied. The results suggest that the significantly different predation amount by adult was due to food preference amoung the different foods.