• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.231-235
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• 2005

This study was conducted to obtain the optimal spray time for Pseudaulacaspis prunicota (Maskell) (Homoptera: Diaspididae) in early seaon in Jeju. Oviposition time of overwintered females and activity of hatched nymphs of P. prunicola were monitored, and the phenology data were compared with the outputs estimated by a degree-days model of P. pentagona (Targioni-Tozzetti)). Overwintered females of P. prunicola began to lay eggs from mid to late April, and the eggs started to hatch from early May followed by the active migration of the hatched nymphs during mid May. The phenological events of P. prunicola in early season were likely comparable with those of P. pentagona reported in southern Korea and in central Japan. A degree-day model, which predicts the proportion of >50% hatched egg batches of P. pentagona (y=1[exp(-(-a+bx))]; y, proportion; x, degree-days based on $10.5^{\circ}C$ from 1 January; a=-18.80 and b=0.073), accurately described the migration time of P. prunicola hatched nymphs. Thus, it is considered that the degree-day model can be used for predicting the optimal spray time for P. prunicola in early season.

• Agrochemical news magazine
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• v.21 no.8 s.161
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• pp.22-25
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• 2000

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.351-358
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• 2006

This study was conducted to evaluate herbicidal properties of picolinafen in terms of crop safety, weed control spectrum, application window, residual efficacy and resistant weed control. Herbicidal phytotoxicity of picolinafen to wheat and barley was greatest when applied at 0 days after sowing (DAS), but decreased significantly as plant growth advanced. Picolinafen showed greater activity against broadleaved weeds than grass weeds. Picolinafen showed highest activity when it was applied at early post emergence timing (5 to 15 DAS), and showed significantly decreased activity at 20 DAS application. The $LT_{50}$ values (the period from application required for residual control by 50%) was 9.3 and 6.5 days against Digitaria ciliaris and Brasica naus at 60 g ai $ha^{-1}$, respectively. Picolinafen showed similar activities against both triazine resistant and sensitive Amaranthus retroflexus. Collectively, picolinafen appeared to have a good fitness to control resistant broad leaved weeds control by early post emergence application.

• Korean journal of applied entomology
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• v.33 no.1
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• pp.1-5
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• 1994

These studies were to observe the pentatomid species of chrysanthemum, and to investigate the h host range of Nysius plebejus DIstant and its control The five pentatomid species of four families w were observed In Chinju and Masan areas. Dominant species was Nysius plebejus DIstant with 80.6% occufied. The host plants of N. plebejus were 20 species in chrysanthemum fields. And major hosts were chrysanthemum morifalium, Lolium multiflorum, Erigeron linifolius and Fragana chiloensls. All the cultivars of C. monfoIium were infested and severely damaged by N. plebeius Appropnate control of N. plebejus was 3~4 applications of the effective insecticides at 10-day intervals from early August.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.353-355
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• 2000

The seasonal occurrence of aphids was investigated in the soybean Held to increase the control efficiency of aphid vectors of Soybean Mosaic Virus. The patterns of aphids occurrence were different according to planting time. There were two peaks in late June and mid-August in aphid population in optimum seeding (May 20), whereas the peak was around mid-June in early seeding(Apr, 20). Acyrthosiphon solani was dominant Species in early seeding, while Aphis glycines was dominant in optimum seeding. In early seeding, SMV incidence increased rapidly between 20 June and 30 June, suggesting that virus spread was strongly correlated with increased colonization of aphids. Imidacloprid WP, benfuracarb EC and acephate WP showed a good effect for the control of aphids without phytotoxicity. In the plot with infurrow treatment of imidachloprid G until 52 days after shooting, aphids were controled effectively. Acephate WP was applied as a foliar spray at V4, V6, or V4/V6 stage and all the treatments were effective on reducing: SMV incidence.

• Korean journal of applied entomology
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• v.18 no.1 s.38
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• pp.55-61
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• 1979

Since rice high yielding practices with blast resistant varieties induced severe and earlier infestation of sheath blight recently, it is strongly suggested to spray at least 10 days earlier than the present recommendation and more than 2 sprays from early July to early August seems to be essential for the efficient control of sheath blight in the future. Among organo-arsenic fungicides, MAFe (Neo Asozin) is known as the most effective and economic as well as with the advantages of free phytotoxicity and safe residure on rice, and applications of the mixed formulation with other fungicide and insecticide is suitable for the one-hit control of rice diseases and insect pests in connection with cooperative mass control system. Present level of arsenic $(As_2O_3)$ residue in .ice is summarized as 0.2ppm to 0.65 ppm in highest average, and there are more possibilities of extensive MAFe fungicide uses for the efficient and economic control of this disease. During the past few years, the acreage of sheath blight control has been extended several times while the increase of the fungicides used for sheath blight showing about 10 times in quantity and mort than 15 times in amount, and also the fungicide cost estimated for the control is differ from 1 to 12 billion 1on by the use of MAFe or antibiotic fungicide in a year.

• Korean journal of applied entomology
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• v.1
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• pp.51-53
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• 1962

1. 본시험은 이화곤충방제에 유효하다고 인정된 신살충제를 선정하여 이화곤충에 대한 살충효과의 재확인 및 살포적기를 구명코저 시행하였다. 2. 제일화기에 있어서 Diazinon, Lebaycild, Endrin 및 Folidol은 부화 14일전 처리로서도 부화유충의 식입제로서 유효하였고, 부화유충 식입후일처리구에 있어서도 무처리구에 비하여 유효하였다. 3. 제2화기에 있어 부화 21일전 처리구의 유효성은 Detron=Folidol>$\gamma$-dol>Endrin>Dimecron의 순이었다. 그리고 부화 14일 및 17일전과 부화 2일 및 7일후 처리에 있어서도 $\gamma-dol$을 제한 다음 약제들은 고도의 유효성을 나타내었다. 4. 그러나 약제처리시기 사이에는 유의성이 없었다. 5. 본시험은 1회의 시험성적임으로 동일시험이 수회반복되어 살충효과 및 살포적기가 완전히 구명되었으면 한다.

• 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.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.9 no.5
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• pp.82-95
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• 1988

9$\cdot$10월은 중$\cdot$만생종의 수확기이다. 이제까지의 고된 작업과 병해충과의 씨름도 어느정도 마무리 단계에 접어들게 되나 아직까지도 자칫 방심하면 다지어 놓은 농사를 망치기도 하고 조기낙엽에 의하여 내년도의 개화결실에도 나쁜 영향을 미치게 된다. 따라서 작업의 선후를 잘 계획하여 한 해의 농사를 마무리 지어야한다. 9$\cdot$10월의 중요한 과수원작업은 착색관리, 적기수확 및 저장, 추비시용인데, 병해충이 많을 때에는 약제방제도 소홀히 할 수 없으며, 태풍의 피해가 우려되는 과수원에서는 이에 대한 대비도 하여야 한다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.10a
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• pp.161-161
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• 2017