• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.179-184
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• 2000

This study was conducted to improve control system of insect pests, especially western flower thrips, Frankliniella occidentalis, and two-spotted spider mites, Tetreanychus urticae, of rose greenhouses. Density of thrips was relatively higher in yellow flowers than in pink or redflowers, while there was no difference in density of two-spotted spider mites by flower colors. In pest control by an automatic monorail sprayer, 89% labor and 18.2% chemical savings, as compared to the conventional high pressure spray method, were achieved without lowering the pest control effectiveness. By using an adhesive agent in combination with acaricide, adhesion of chemical to crops increased by 25% and control effect on two-spotted spider mites increased by 20.5% as compared acaricide spray alone.

• Korean journal of applied entomology
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• v.62 no.1
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• pp.43-48
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• 2023

The efficacy of spinetoram sprayed from an unmanned helicopter to control two insect vectors of pine wood nematodes, Monochamus alternatus and M. saltuarius was assessed. By using a ULV (Ultra Low Volume) sprayer, the mortality rates of phenthoate, bifenthrin, etofenprox, and diflubenzuron, which are registered for use against coleopteran insects, indoxacarb and spinetoram, which are registered for use against lepidopteran insects, were evaluated for efficacy as aerial spraying agents. The ULV test, using 33- and 55-fold dilutions of phenthoate, bifenthrin, indoxacarb, and spinetoram demonstrated a 100% insect mortality rate upon contact and feeding mortality on the third day after treatment, while etofenprox and diflubenzuron exhibited a slightly lower mortality rate than the remaining compounds. Consequently, spinetoram was selected as a candidate pesticide for aerial spraying and its efficacy to control the insect vectors was assessed. The x 33 dilution of spinetoram resulted in a 98.6-100% control efficacy against two insect vectors. However, risk assessment for bees following aerial spraying will be necessary before applying the pesticide to control insect vectors.

• International Journal of Industrial Entomology and Biomaterials
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• v.22 no.1
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• pp.25-28
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• 2011

The virulence against the two-spotted spider mite, Tetranychus urticae Koch, was evaluated with entomopathogenic fungus Paecilomyces lilacinus (Thom) Samson HY-4 which is isolated from coleopteran insect and registered to Korean and US patents. Virulence tests were conducted with conidial suspensions ($1.5{\times}10^6conidia/ml$) of P. lilacinus HY-4 against T. urticae adults and positive results were recorded in laboratory conditions. The spraying device was also developed for the efficient and exact evaluation of treatment. The developed spraying device was named as SD-tower sprayer and its efficacy of spraying conidia was evaluated. The accumulated mortality caused by P. lilacinus HY-4 using SD-tower spray was about 73% at 6 days after inoculation. This suggest that the isolate P. lilacinus HY-4 may be considered as promising for a new approach to prevent adult infestations by T. urticae.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.2
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• pp.3758-3762
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• 1975

In order to find out the optimum size of nozzle of the power sprayer in the paddy field, four different sized hole of nozzles were tested on its discharge volume per unit time and its effective covering distance. 1. The discharge rate of each nozzle is proportional to square root of the transmitted internal pressure of liquid, and the discharge coefficient ranges from 0.82 to 0.86 at the pressure of 20 to 30 kg/$\textrm{cm}^2$. 2. The effective covering distance is increased as the size of the hole is larded and also the pressure is increased under under the limited pressure. Generally, the effective covering distance is not greatly increased at the pressure of above 25kg/$\textrm{cm}^2$. The distance from the nozzle to the spot where the largest amount of droplets are dropped is about 14.5m for 3.05mm nozzle and 16m for 4.05mm nozzle in the pressure range from 20 to 25kg/$\textrm{cm}^2$. 3. From the above results it is concluded that the 3mm nozzle with the power sprayers, which are now being supplied to the farmers, can be used for disease and insect control on the paddy field of which block size is 30m${\times}$100m, and operators need not to enter the field for spraying. For the 40m${\times}$100m block, 4mm nozzle should be used with large size of pump which discharge capacity is 60l/min or more.

• Korean journal of applied entomology
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• v.33 no.3
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• pp.201-206
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• 1994

Trunk implantation method of phosphamidon 50% Lq.is commonly applied to control the pine needle gall midge (Thecodiplosis laponensts Uchida et Inouye) Since trunk implantaion is normally practiced during the late Spring, it is often difficult to accommodate necessay labor in mral area. As an alternative, aerial spraylng of less toxic ~nsecticide was designed. Usage of less toxic insecticide in the aenal control of pine needle gall midge can reduce the damage to forest ecosystem. The buproferin, one of the insect growth regulator, was selected at d~fferent rate of dilutions and the treatments effects ruere evaluated at different date and time When 50 t~mes diluted solution of buprofezin 40% SC was treated on different period, there was no significant difference in dficacies. the control efficacies of buproferin 40% SC was measured by occurrences (%) of gall formation of the pine needle gall midge using a ultra low volume (ULV) sprayer and the dilutions of 10X 30X and 50X of buprofez~n 40% SC gave efficacies. 72.4. 57.6 and 8.4, respectively.

• Journal of Bio-Environment Control
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• v.31 no.1
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• pp.52-59
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• 2022

Pest control treatment was carried out using an unmanned automatic pesticide spraying system that can spray pesticides on crops while moving autonomously to control pests in vegetable greenhouse. As a result of examining the control effect on tomato and strawberry on thrips (Frankliniella occidentalis) and greenhouse whitefly (Trialeurodes vaporariorum) pests, 85.6% of yellow flower thrips were found in tomatoes and 87.5% in strawberries, and 81.7% (tomato) and 80.6% (strawberry) of greenhouse whitefly. In addition, the control effect according to the pesticide treatment method showed a control effect of 81.7% of the chemical spraying treatment by manpower and 83.9% of the automatic moving pesticide spraying treatment (F=22.1, p < 0.001). When comparing the control effect between the two treatment sections, there was no significance, but the automatic transfer spraying treatment showed a 2.2% higher effect. On the other hand, as a result of comparing the spraying time of the drug, the automatic unmanned control sprayer had a spraying time of 5 min/10a, which took about 25 min less than the conventional manpower spraying time of 25-30 min/10a. Based on these results, it was judged that the automatic transfer spraying method could be usefully used for efficient pest control in the facility greenhouse during the peak period of development.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.411-418
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• 2013

The black pine bast scale, Matsucoccus thunbergianae is one of the most serious insect pest in Japanese black pine, Pinus thunbergii forest in Korea. Insecticidal activity of 10 folds hot water extracts from 7 herbal plants (Atractylodes lancea, Eugenia caryophyllata, Lonicera japonica, Melia azedarach, Quisqualis indica, Sophora flavescens and Taraxacum mongolicum) were tested against different stage of M. thunbergianae using spray method both in laboratory and field. Efficacies of herbal extracts were different depending on stage of M. thunbergianae. Q. indica sprayed with hand sprayer produced the highest corrected mortality of 95.7% on intermidiated nymph stage, however, A. lancea produced the highest corrected mortality (51.3%) on pupae of M. thunbergianae in laboratory. Q. indica and A. lancea were highly effective against female M. thunbergianae in laboratory, however, corrected mortality was lower than other stage (40.0%). Efficacy of Q. indica was similar to effective insecticide, fenitrothion 50% EC against M. thunbergianae in field trials. These results indicated that Q. indica could be an environmental friendly control agent of M. thunbergianae.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.192-197
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• 1979

Spread factors were tried to determine the diameter of airborne droplet emitted: from the sprayer by the measurements of airborne droplet diameter emitted from the uniform size droplet producer and impression diameter on Kromekote card or Eucalypt's leaf in the different dilute concentration with Geigy Red Herbicide Dye from 0.5% to 2% by weight. The results abtained were as follows; The general form of the equation in the relationship between airborne droplet and impression diameter on Kromekote card or Eucalypt's leaf was an exponential equation as follows; $$Y=aX^b$$ which gave a linear relation on log-log graph paper. The spread factor seemed to be larger in the thin dilute concentration than in the thick dilute concentration. The spread factor was remarkably smaller on Eucalypt's leaf than on Kromekote card due to the penetration of liquid into the leaf and the stomata of the epidermis. The calculated equation of the mean depth of the droplet sprayed on Eucalypt's leaf was the same form as $Y=aX^b$, which implied that the spray liquid was distributed in surplus in accordance with the diameter of the droplet larger than the optimum size droplet to control insect and disease.