• The Plant Pathology Journal
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• v.29 no.3
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• pp.294-304
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• 2013

To improve the integrated pest management (IPM) of hot pepper, field study was conducted in Hwasung from 2010 to 2012 and an IPM system was developed to help growers decide when to apply pesticides to control anthracnose, tobacco budworm, Phytophthora blight, bacterial wilt, and bacterial leaf spot. The three field treatments consisted of IPM sprays following the forecast model advisory, a periodic spray at 7-to-10-day intervals, and no spray (control). The number of annual pesticide applications for the IPM treatment ranged from six to eight, whereas the plots subjected to the periodic treatment received pesticide 11 or 12 times annually for three years. Compared to the former strategy, our improved IPM strategy features more intense pest management, with frequent spraying for anthracnose and mixed spraying for tobacco budworm or Phytophthora blight. The incidences for no pesticide control in 2010, 2011, and 2012 were 91, 97.6, and 41.4%, respectively. Conversely, the incidences for the IPM treatment for those years were 7.6, 62.6, and 2%, and the yields from IPM-treated plots were 48.6 kg, 12.1 kg, and 48.8 kg. The incidence and yield in the IPM-treated plots were almost the same as those of the periodic treatment except in 2011, in which no unnecessary sprays were given, meaning that the IPM control was quite successful. From reviewing eight years of field work, sophisticated forecasts that optimize pesticide spray timing reveal that reliance on pesticides can be reduced without compromising yield. Eco-friendly strategies can be implemented in the pest management of hot pepper.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.9
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• pp.34-42
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• 2010

Agricultural automation has become more and more important by environmental change. The automation demands the highest technology due to the ever changing various conditions in agriculture system. In the paper, semi-autonomous pesticide spray robot system has been developed for rose farming in the glass house. The robot is in autonomous mode during pesticide spraying process driven on pipe rail. The robot is manually driven while moving from a rail to the next rail. The drive platform and autonomous operation control system are developed based on IT fusion technology. The pesticide spray system is also developed with nozzles and booms for precision mist spray system. Experimental data of nozzle test is also included.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.336-342
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• 2012

This study was carried out in order to compare the residue levels of pesticides among lettuce, kale and perilla leaf depending on the morphological characteristics of plant. Residue levels were investigated at the zero, second, fifth days after last application, 9 species of systemic or non-systemic pesticide were twice applied with 7 days interval by knapsack power sprayer with 2 heads fan shape nozzle. Ratios of leaf area to weight ($cm^2$ $g^{-1}$) were 58 of perilla leaf, 27 of lettuce and 23 of kale. Ratios of leaf area to weight of perilla leaf was 2.1 times higher than that of lettuce. Residue levels of perilla leaf were 1.3 to 2.3 times higher than those of lettuce at the day of spraying and 1.3 to 3.3 times higher at the fifth day. Therefore the differences of pesticide residues between perilla leaf and lettuce were affected by the ratio of leaf area to weight. Residue levels in lettuce were 2.4 to 7.3 times higher than those in kale at the day of spraying because the adhesive effect of pesticide particles on kale leaf was low.

• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.350-357
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• 2014

We studied on pesticide residue and pest control effect when using various types of sprayers on paprika cultivation. Additionally, a test was conducted to optimize chemical content per unit area in condition of optimum pest control. Two types of sprayer were tested (three times) on paprika cultivation which was divided into seven sections. Blind spots were also examined using a water sensitive paper when spraying chemical pesticide, remote controlled sprayer were confirmed to be not effective in terms of its spraying capacity. However, a U-shaped sprayer was confirmed that it sprayed enough on all the parts of a plant in green house including the blind spots. Additionally, it does not exceed the minimum residue limits on the all parts of pesticides residue conditions. When using remote controlled sprayer, water sensitive paper were changed to blue color (82.5% and 81.2%) in terms of controlling Bemisia tabaci and Aphis gossypii based on the two spraying manners. 53.0% and 42.6% of control effect were shown on the fair parts of the plants. However, on the poor parts on which pesticides were not well-sprayed, thus, not-remained, more number of pests increased. Meanwhile, on farming that only one type of pesticide has been used, resistance pests present with very low control effect, even though sufficient amount of pesticide was well-sprayed. On the test of the optimum amount of spraying per a unit area, which shows no differences in the two cases of using 5L and 2.5L of chemical pesticides on 9 plants of paprika that has 81.8% and 84.5% control effect, respectively.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.213-220
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• 2018

BACKGROUND: This study was carried out to determine characteristics of residual pesticides in time-dependent manner and calculate half-lives of the residual pesticides in fresh and dried Chinese matrimony vine. In addition, processing factors were calculated based on the residual concentrations in them. METHODS AND RESULTS: The test pesticides, etofenprox and fenitrothion, were sprayed onto the Chinese matrimony vine plants at once or twice (at seven-day interval) and then samples were collected at 0 (after 3 hours), 1, 3, 5 and 7 days after the last spraying. Dried samples were prepared in hot-air drying oven at $60^{\circ}C$ for 48 hours until water content of less than 20%. Residual concentrations of etofenprox in fresh and dried samples decreased by 54.0-60.9% after 7 days of the last pesticide-application. In case of fenitrothion, the concentrations were found to have decreased by 69.2-76.5%. Processing factors of etofenprox were 2.6-3.0 for the one-time spraying and 2.5-3.0 for the two-time spraying and those of fenitrothion were found to be 1.5-22 for the one-time spraying and 1.6-2.0 for the two-time spraying. First half-lives of etofenprox and fenitrothion in fresh and dried samples ranged from 5.0 to 6.3 and from 3.4 to 4.0 days, respectively. The third half-lives were found to be 15.0-18.9 and 10.2-12.1 days, respectively. CONCLUSION: Residual concentrations of the tested pesticides in the studied crop decreased, but those in the dried samples appeared to have increased. In addition, processing factor and half life were constant regardless of spraying times.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.366-373
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• 2011

This study was conducted to identify the residue patterns of fungicide boscalid in ginseng cultivated for 4 or 6 years treated by various spraying methods. The pesticide was sprayed separately on ginseng according to safe use guideline, and the field was divided into three groups and they were traditional, soil and vinyl mulching applications. The maximum residue amounts of boscalid were 0.76 mg/kg in traditional application group, 0.69 mg/kg in soil application group, 0.62 mg/kg in vinyl mulching application group in the whole part of 4 years old ginseng, respectively. These residue levels in ginseng exceeded the maximum residue limit established by Korea Food & Drug Administration, which is 0.3 mg/kg.

• Journal of Information Processing Systems
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• v.15 no.5
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• pp.1131-1140
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• 2019

Characteristics of fruit tree canopies are important target information for adjusting the pesticide application rate in variable rate spraying in orchards. Therefore, the target detection of the canopy characteristics is very important. In this study, a canopy volume measurement method for peach trees was presented and a variable rate spraying system based on canopy volume measurement was developed using the ultrasonic sensing, one of the most effective target detection method. Ten ultrasonic sensors and two flow control units were mounted on the orchard air-assisted sprayer. The ultrasonic sensors were used to detect the canopy diameters and the flow controls were used to modify the flow rate of the nozzles in real time. Two treatments were established: a constant application rate of $300Lha^{-1}$ was set as the control treatment for the comparison with the variable rate application at a $0.095Lm^{-3}$ canopy. The tracer deposition at different parts of peach trees and the tracer losses to the ground (between rows and within rows) were analyzed in detail under constant rate and variable rate application. The results showed that there were no significant differences between two treatments in the liquid distribution and the capability to reach the inner parts of the crop canopies.

• The Korean Journal of Pesticide Science
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• v.12 no.2
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• pp.118-126
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• 2008

In order to find the best compositions of the dimethomorph formulation containing fatty alcohol ethoxylate surfactants as an activator adjuvant and recommend the good management way of the formulations to allow an intended uptake rate, factors affecting foliar uptake of active ingredients into cucumber were investigated and compared each other. Among tested, the most important factors were air temperature in which plants were located after spraying of aqueous formulations containing activator adjuvant, and deposit of wax on the leaf surface of cucumber. Dimethomorph uptake was found to be increased by sunlight. When aqueous formulations had long-polyethoxylated fatty alcohol surfactants, the relative humidity of the room in which the plants were located after spraying with the formulations did not severely influence the foliar uptake. Maintaining a mild temperature and avoiding too strong sunlight after spraying with dimethomorph formulations were found to be resonable management strategies.

• The Korean Journal of Pesticide Science
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• v.6 no.3
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• pp.175-182
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• 2002

This experiment was conducted to investigate the effects of acid rain in spraying copper hydroxide 77% wettable power(WP) on leaf surface morphology and crop injury of the garlic(Allium sativum L.). Leaf chlorosis, hooked leaves, wrinkled epidermal cells and increased stomata open of garlic were induced by foliar application of simulated acid rain(SAR). It was become to be severe in application of copper hydroxide solution after application of SAR, but those yield of garlic was not significantly different from the untreated control. Leaf chlorosis was sharply increased above 100 ppm of copper ions. Amount of solved copper ions in copper hydroxide solution was remarkably increased below pH 5.5 and the residue in garlic leaves was significantly increased by application of copper hydroxide solution after spraying SAR compared with application of copper hydroxide solution only. When calcium carbonate was applied together with copper hydroxide leaf chlorosis was less than copper hydroxide only.

• The Korean Journal of Community Living Science
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• v.17 no.4
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• pp.49-56
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• 2006

The purpose of this study was to evaluate the thermal and subjective comfort of various pesticide-proof clothes made from different material. Seven male adults took part in the study, conducted in a climate-chamber controlled with an ambient temperature of $30^{\circ}C$ and a relative humidity of 60%RH. The thermal and subjective responses of subjects wearing pesticide-proof clothing made of Goretex(coating treatment), polyester (water-repellent treatment), non-woven(coating) and nylon(coating) were measured. The main results were summarized as follows: (1) Change of rectal temperature and clothing microclimate were inhibited more effectively in pesticide-proof clothing made of Goretex, polyester and non-woven than nylon materials. (2) Mean skin temperature at the end of the experiment was significantly higher in subjects who wore nylon than non-woven and Goretex, and was lowest in those with pesticide-proof clothing made of polyester. (3) Change of heart rate was significantly lower in subjects with Goretex and polyester clothiing than those with non-woven, and in those with nylon, it was highest. (4) Subjective comfort was greater in subjects with Goretex, polyester and nonwoven clothing than nylon, except for thermal sensation. Thermal sensation was greater in order of polyester, Goretex, non-woven and nylon. Thus, it was concluded that pesticide-proof clothing made of Goretex, polyester and non-woven material could reduce thermal stress during the spraying of pesticides in summer.