Aphis gossypii was widely distributed throughout the tropical, subtropical and temperate zone. The chemical control of A. gossypii is becoming problem because it was rapidly appeared resistance expression to chemicals. We will attempt to resolve the this problem using RNAi technique. Besides, RNAi technology can be helpful to study the target genes of A. gossypii. In this study we produce cDNA library construction using gateway cloning system for selecting target gene in order to control of A. gossypii using RNAi. As a result, the 100-400bp of insert size, which is appropriate for RNAi was confirmed. Most of insert gene is associated with A. gossypii, after that insert sequence was compared with DNA databases and EST databases using NCBI blast search. Consequentially, A. gossypii of cDNA library with the titer of 3.15x105 clones were completed. And we will perform the LR recombination to transfer cDNA library into TRV2 (tobacco rattle virus) vector with att site. Then, after performing transformation using Agrobacterium tumefaciens (GV 2260), we inoculated to cucumber with A. tumefaciens. An insecticidal effect or a repellent activity against A. gossypii by changing behavior in transgenic cucumber plants were conformed. Also, the selecting target gene in order to control A. gossypii using RNAi may be provided.

도시 텃밭에서 재배되는 농산물의 대부분은 식탁에 바로 오르는 채소류로 안전성 확보가 요구되나 아직 이에 대한 자료가 없다. 본 연구는 도시 텃밭에서 재배되는 채소류의 생물학적 안전성을 평가하기 위한 기초 자료를 확 보하기 위하여, 2012년 9월부터 10월 사이에 서울시내 11 곳의 도시텃밭에서 채취한 9종 채소류(배추, 상추, 무잎, 시금치, 겨자잎, 쑥갓, 파, 양배추와 치커리) 530 표본을 대상으로 총호기성균(일반세균), 대장균/대장균군, Salmonella spp. Listeria monocytogenes 및 E. coli O157:H7 오염 수준을 정량적으로 혹은 정성적으로 평가하였다. 조사한 농산물에 존재하는 총호기성 세균과 대장균군의 평균 수는 각각 6.3 log CFU/g (범위, 3.8-8.1 log CFU/g) 및 4.3 log CFU/g (범위, 2.1-6.4 log CFU/g) 이었다. 대장균군은 전체 표본의 67%에서 발견되었다. 치커리에서 가장 많은 수의 총호기성 세균과 대장균군이 검출되었고, 부추에서 가장 적은 수의 대장균군 오염을 보였다. 대장균은 전체 채소류의 2.3%에서 발견되었으나, 농산물별로는 상추, 무잎, 갓과 치커리에서 발견되었다. 그렇지만, 조사한 농 산물에서 식중독 유발 세균인 Salmonella spp., L. monocytogenes 및 E. coli O157:H7은 검출되지 않았다. 이상의 결과로 보아, 서울시내 도시텃밭에서 재배되는 채소류에서 식중독 유발 세균은 발견되지 않았으나, 재배 과정중 대장균군 및 대장균의 오염을 줄이기 위한 노력이 요구된다.

Many community gardens in large cities worldwide grow vegetables; however, no information regarding the levels of sanitary indicator bacteria and prevalence of foodborne pathogens in vegetables grown in urban community gardens is available. To evaluate the microbiological quality of vegetables from urban community gardens in Korea, 530 samples (nine types of vegetable, including Chinese cabbage, lettuce, radish leaves, spinach, mustard leaves, crown daisy, leek, Korean cabbage, and chicory) were collected at 11 urban community gardens in Seoul, Korea from September through October 2012. The levels of total aerobic bacteria, Escherichia coli, total coliforms, Salmonella spp. Listeria monocytogenes, and E. coli O157:H7 were evaluated quantitatively and/or qualitatively. The mean numbers of total aerobic bacteria and coliforms were 6.3 log CFU/g (range 3.8-8.1 log CFU/g) and 4.3 log CFU/g (range 2.1-6.4 log CFU/g), respectively. Total coliforms were detected on 67% of whole vegetables. Chicory showed the highest number of total aerobic bacteria and coliforms, whereas the lowest number of coliforms was detected on leeks. E. coli was detected on 2.3% of whole vegetables, including lettuce, radish leaves, mustard leaves, and chicory; however, foodborne pathogenic bacteria were not detected on any of the vegetable samples using this highly sensitive and validated procedure. Based on these findings, the presence of coliforms and E. coli demonstrates that opportunity for improvement of microbiological safety exists throughout the produce production chain, although no major foodborne pathogens were present in vegetables grown in urban community gardens.

This study was examined for activity of aggregation pheromone trap with residual effect of insecticides against Riptortus pedestris. Time of escape was from aggregation pheromone trap researched 49.74 min (ET99) and 65.01 min (ET99) with 1st and 2nd instar nymph respectively. Six insecticides for the stink bugs were treated to 3 different materials (wood, metal, and plastic). Bifenthrin and fenitrothion were showed 100% insecticidal activity at 48 h to all developmental stage of R. pedestris. Residual effect of bifenthrin and fenitrothion on plastic material were showed 100% insecticidal activity over 15 day after treatment with 1st, 3rd instar nymphs, and adults except 5th instars nymph. In field test using plastic material trap with two pesticides, 1st instar nymphs and adults were showed 100% mortality until 10 day after treatment. These results indicate that R. pedestris might be managed using aggregation pheromone trap with insecticides.

Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseidae) is well known as an effective natural enemy of two-spotted spider mite, Tetrnychus urticae Koch (Acari: Tetranychidae). However, successful biological control usually requires adequate management of temperature. While P. persimilis did suppress T. urticae at moderate condition (20~25oC) in a week or so, the density of P. persimilis was barely increased at cold condition (5~10oC) in three weeks or so. The problem is that winter temperature is too cold for the development and reproduction of P. persimilis in greenhouse for forcing strawberry. Night temperatures in greenhouse were even mostly lower than 6oC. So, winter application of P. persimilis against T. urticae is useless. To avoid damage from T. urticae in early spring season, it was better that the release amount of P. persimilis was double at middle- and late-October, instead of early-November to next early-February. If necessary, the double releasing of P. persimilis might be good for control of T. urticae at middle- and late-February.

Strawberries are among the leading ready-to-eat agricultural products that have superior taste and nutrition. Thus, consumer concerns about the safety of eating strawberries are growing. To evaluate the contamination levels of strawberries according to their cultivation methods (nutriculture, pesticide-free culture and organic farming) and parts [fruit (flesh), stalk (pedunle) and leaf (calyx)], 1,020 parts of strawberry samples were collected at 12 farms in Nonsan-si and quantitatively or qualitatively examined for the indicators of food safety and food poisoning bacteria. The total aerobic bacteria count in the whole samples was 2.3~6.8 log10 CFU/g, and coliform bacteria were detected in 14.2% of the whole samples with a contamination level range of 2.1~4.5 log CFU/g. E. coli were detected in 0.9% of the whole samples with a contamination level range of 2.1~2.8 log CFU/g. The analysis of the bacterial levels according to the cultivation methods showed that the total aerobic bacteria and coliform counts were higher in the strawberries that were grown via organic farming than in those that were grown via nutriculture and pesticide-free culture. However, the E. coli counts of the strawberries that were grown via organic farming and via pesticide-free culture were similar and differed from that of the strawberries that were grown via nutriculture. The analysis of the contamination levels according to the parts of the strawberries showed that the total aerobic bacteria, coliform and E. coli counts of the fruits, stalks and leaves of the strawberries did not significantly differ. Staphylococcus aureus was detected in two organically grown strawberries, but Salmonella spp., Listeria monocytogenes and E. coli O157:H7 were not detected in the whole samples. These results show that the bacterial contamination levels of the strawberries differed based on their cultivation methods. Thus, a suitable method of reducing the bacterial contamination levels of strawberries according to their farming methods is needed