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This study was carried out to investigate the pesticide residue pattern among different leafyvegetables applied with foliar spraying under greenhouse and to check extrapolating from some residue trialdata to other minor crops. Leafy vegetables used in this study were: Mustard greens (Brassica juncea L.),Kale (Brassica oleracea L.), Dacheongchae (a kind of pak-choi (Brassica rapa subsp. chinensis L.)), Leafbroccoli (Brassica oleracea var alboglabra), Perilla leaf (Perilla frutescens (L.) Britton var. Frutescens), Leaflettuce (Lactuca sativa L.), Swiss chard (Beta vulgaris L. subsp. vulgaris) and Red leaf chicory (Cichoriumintybus L. var. foliosum Hegi). These are cultivated all year under indoor or outdoor and cut the leaf fromplant continuously during harvest time. The amounts of pesticide deposit in/on the continuous harvestingleafy vegetables were affected by the ratios of leaf area to weight. Ratio of perilla leaf was the largest amongcrops as 58 cm 2 /g. The residue levels of 7 pesticides in/on perilla leaf were the highest than those of othercrops through the statistical analysis from zero day to fifth day after last application. The representative cropin 8 crops was perilla leaf selected based on the amounts of daily consumption and the high residues. This studysuggest that the continuous harvesting leafy greens should be separated from the one time harvesting leafyvegetables for the pesticide recommendations because of different harvesting habits and pre-harvest intervals.Key words Extrapolation, Perilla leaf, Leafy vegetables, Pesticide residue, Continuous harvesting

Pesticides were sprayed on perilla leaf and leafy lettuce in a greenhouse and the reduction rate ofpesticide residues on each vegetable by washing were tested. The reduction rate of pesticide residues bywashing for 30 sec~3 min on perilla leaf were 3~63% in tap water, 2~58% in salt water, 6~74% in green teawater, and 8~86% in detergent solution. The detergent solution only showed significant difference inreduction rates compared to the tab water washing. Considering reduction effects of the washing duration, itwas showed that the reduction rates were a pattern of inclining as the duration of washing process increased,but there was no significant difference in the reduction rates except the reduction rates between washing inthe detergent solution for 1 min and 3 min. Comparing washing in flowing tab water and in stagnant tabwater with leafy lettuce, the reduction rate by one time washing were 8~68% in flowing tab water and7~64% in stagnant tab water. The water and the time used in this experiment were 17.5 L, 2.9 min withflowing tab water and 4 L, 1 min with stagnant tab water. The reduction rate by 3 times washing in stagnanttab water were 16.5~76.6%, and the water and the time used were 12 L, 3 min. Therefore, when the waterand the time used to wash vegetables were considered, washing two or three times in stagnant tab watercould be more effective than washing one time in flowing tab water.Key words Pesticide residue, Leafy vegetable, Washing, Reduction

This study was conducted for the establishment of the analytical method of pesticide residues in rice straw for 9 pesticides; etofenprox, tricyclazole, diazinon, edifenphos, propiconazole, carbaryl, carbofuran, 3-hydroxy carbofuran and 3-keto carbofuran and for the monitoring of these pesticides in rice straw for livestock feed in Korea. These pesticides were classified into 4 groups according to analytical instrument condition. Group 1 (HPLC-UVD1) included tricyclazole and etofenprox while group 2 (HPLC-UVD2) included propiconazole and edifenphos. Group 3 (HPLC-FLD) included carbaryl, carbofuran, 3-hydroxy carbofuran and 3-keto carbofuran. Group 4 (GC-NPD) included Diazinon. The dried rice straw samples were extracted with acetone and purified by liquid-liquid partition and solid phase extraction (SPE): Combination of Florisil SPE and amino-propyl SPE was used for group 1 and group 2, amino-propyl SPE for group 3, and Florisil SPE was for group 4. Recovery was in the ranged 70~110% and the limits of quantitation (LOQ) were lower than the half of maximum residue limits. Therefore this method was proved to be efficient for monitoring of these pesticides residue in rice straw. A total of 18 rice straw samples from 6 provinces in Korea in 2010 were analyzed using established method and, only 3-keto carbofuran was detected in one sample at concentration of 0.04 mg/kg. Key ward Rice straw, Pesticide residue, Analytical method, Monitoring

Fate of acetamiprid and imidacloprid aerially sprayed to control pine wood nematode (Bursaphelenchus xylophilus) were studied in a forest of Haman area. Acetamiprid 20% SL or imidacloprid 20% DC were diluted 100 times and applied two times as rate of 50 L/ha using an aircraft of Bell 206 L helicopter. Average acetamiprid deposits on forest floor ranged from 2 to 4% of standard aerial application rate. Following to the second application, acetamiprid deposits in the pine needle ranged 1.8~8.5 mg/kg and then gradually decreased to 1.2~2.1 mg/kg after 48 days. Deposits on the plant washed off by rainfall and reached to soil surface was ca. 17% of the application rate. All of acetamiprid on the ground resided in the forest floor covering the soil surface, where acetamiprid residues were decreased to a quarter at 48 days after the second application, but they were not detected in soil beneath it. And the only low level of acetamiprid residues, 0.0003 mg/L, was detected in the reservoir nearby the experimental forest on the day of aerial application. The acetamiprid detection was presumably due to spray drift. And average imidacloprid deposits on forest floor ranged from 1 to 3% of standard aerial application rate. Following to the second application, imidacloprid deposits in the pine needle analysed very low concentration of 0.1 mg/kg, but the amount of imidacloprid in wash-off in standard and two-fold treatment were ca. 8% and 4% of the application rate, respectively. Most of imidacloprid on the ground also resided in the forest floor, where imidacloprid residues were decreased to a twentieth at 111 days after the second application, and they were detected below 0.5% of the application rate in sol beneath it. And the low level of imidacloprid, 0.0003~0.0017 mg/L, were detected in the streams in the experimental forest. It was not to the level of contamination concerns.

This study was carried out to clarify effects of field location and sprayer on the level of pesticide residue in chilli peppers. As confirmed by statistical analysis, the residue levels in green pepper among three greenhouses did not show significant difference at the first day after spraying with the same engine sprayer and nozzle. But the residue levels in green peppers collected from the exposed outside of crop were 2 times higher than those from the hidden inside. The sampling site was one of variation elements of pesticide residue. The residue levels after application by knapsack engine powered sprayer were 1.7 times higher than those by manual compressed sprayer. As the spraying pressure of the engine power sprayer is 2 times higher than the commonly used pressure of the manual compressed sprayer, the pressure of the sprayer and nozzles were considered to affect on the residue levels in peppers.

The characteristics of chlorpyrifos was studied to clarify the effect of the cultivation season,spray intervals, spray volume and concentration on residues in chilli and sweet peppers cultivated undergreenhouse condition. Residue levels of chlorpyrifos detected in chilli pepper fruit cultivated were 1.5 to 2.7times higher in winter(February-March) than those in summer(June-July). During winter season residue levelsof chlorpyrifos in chilli peppers were 6.9~3.2 times higher than those in sweet peppers for 10 days after 3times application with 7 days interval. Residue levels in chilli pepper were from 2.070 mg/kg at 1 day to0.929 mg/kg at 10 day, while those in sweet pepper were from 0.302 mg/kg to 0.291 mg/kg. Residue levels insweet pepper to which are 3 times applied with 7 days interval were from 0.302 mg/kg at 1 day to 0.291 mg/kg at 7 day, and the residue levels in sweet pepper which are 3 times applied with 3 days interval were from0.498 mg/kg at 1 day to 0.470 mg/kg at 7 day. Residue levels of chlorpyrifos in the sweet peppers applied bydouble concentration were 2.5 times higher than those sprayed by normal standard amounts diluted in doublevolume. Key words Chlorpyrifos, Sweet pepper, Chilli pepper, Pesticide residue