• Korean Journal of Plant Tissue Culture
• /
• v.24 no.5
• /
• pp.305-311
• /
• 1997

Bacillus thuringiensis, a gram-positive soil bacterium, is characterized by its ability to produce crystalline inclusions during sporulation. The crystal proteins exhibit a highly specific insecticidal activity. An insecticidal crystal protein (ICP), Cry II A, is specifically toxic to both lepidopteran and dipteran insects. In this study, tobacco plants transformed by the cry II A gene have been generated. The Cry II A crystal protein was purified from E. coli JM103 harboring cry II A gene by differential solubility. The activated Cry II A was prepared by tryptic digestion. The purified protoxin (70 kDa) and the activated toxin (50 kDa) were analyzed by SDS-PAGE. To generate the transgenic tobacco having cry II A gene, the cry II A gene was subcloned to a plant expression vector, pSRL2, having two CaMV 35S promoters. The recombinant plasmid was transformed into tobacco (N. tabacum var. Petit Havana SR1) by Agrobacterium-mediated leaf disc transformation. Through the regeneration, six putative transgenic tobacco plants were obtained and three transformants were confirmed by Southern blot analysis. It has been found that one plant had single copy of cry II A gene, another had two copies of the gene, and the third had a truncated gene. After the immunochemical confirmation of cry II A expression in plants, the transgenic tobacco plants will be used to study the genetics of future generation with the insecticidal crystal protein gene cry II A.

• The Korean Journal of Pesticide Science
• /
• v.11 no.1
• /
• pp.52-58
• /
• 2007

ALA (5-aminolevulinic acid) has been proposed as a tetrapyrrole-dependent photodynamic herbicide and insecticide by the action of the protoporphyrinogen IX oxidase (Protox IX). The present study was conducted to determine growth responses of plant and insects to ALA, biodegradable biopesticidal substance. In the paddy condition experiment, plant height and shoot fresh weight of barnyardgrass (Echinochloa crus-galli) was more reduced by ALA than rice plants, even though both plant species show great phytotoxicity. Hairy crabgrass (Digitaria sanguinalis), a monocot weed, was more sensitive to ALA at 5mM under upland condition when ALA applied on the foliage, compared with soybean (Glycine max) as a dicot crop. ALA solutions were tested for their insecticidal and larvicidal activities against Spodaptera exigua (Hubner) and Tetranychus urticae Koch. by foliar application and leaf-dipping method. The result showed higher insecticidal activity of ALA at 10mM and its mixture with insecticide luferon against S. exigua. Strongest insecticidal activity against T. urticae was observed from the ALA solution at 10mM 72 days after application. This results show that ALA solution had potent herbicidal and insecticidal activities against agricultural pests even though their activities were lower than those of synthetic pesticides.

• Journal of Environmental Science International
• /
• v.19 no.12
• /
• pp.1335-1341
• /
• 2010

Voltammetric diagnostics of pesticide thiram was studied in plant leafs in vivo fluid with DNA immobilized on a carbon nanotube electrode (DCE). Sensor properties of carbon nanotube (CE) and DNA immobilized nanotube were compared. DCE was more effective than CE in target detecting. The parameters such as pH strength, stripping accumulation, amplitude, and increment potential were examined to find the optimum condition for detection of pesticide thiram in a sesame leaf. The optimized conditions were as follows 550 Hz frequency, 0.15 V amplitude, 0.005 V increment potential, -1.2 V initial potential, 4.78 pH, 500 sec accumulation time. Under optimum condition, the detection limit of thiram was attained at 0.01ng/L.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
• /
• v.6 no.9
• /
• pp.65-72
• /
• 1985

시설하에서 재배되는 채소류가 생육이 순조롭지 못하다던지 경엽은 생육하고 있더라도 착과되지 않거나 착과되더라도 모양이나 품질면에서 상품성이 낮은 것이 수확되는 경우가 많은데 그 원인으로는 병충해와 생리장해가 있다. 채소류가 생리장해를 일으키는 원인은 뿌리의 손상, 지상부가 생육이 불량하게되는 토양환경 및 비료조건의 불량, 지상부에 영향이 크게 나타나는 기상환경의 불량, 접목장해, 살균제, 살충제, 제초제, 생장조절 등의 살포에 의한 직접, 간접적 약해 등으로 나눌 수 있다. 이들 원인은 실제로는 서로 영향을 주어서 장해를 크게 하는 것이 많다. 또 장해는 주로 경엽이나 뿌리에 발생하고 장해가 심해지면 꽃이나 과실에 미치는 것과 꽃과 과실에만 나타내는 것이 있다. 우리나라에서 시설재배면적과 경제성이 크고 생리장해가 심한 오이와 토마토의 과실에 나타나는 생리장해를 중심으로 그 원인과 대책에 관해서 기술코저 한다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
• /
• v.3 no.6
• /
• pp.34-44
• /
• 1982

1970년대 초부터 본격적으로 도입되기 시작하여 1974년 이래 급속한 사용증가를 기록한 우리나라의 벼농사용 제초제는 1980년을 최고로 95$\%$ 이상의 농가에 의해 매년 사용되고 있다. 1982년 5월 현재 정부에 의해 논잡초약으로 고시된 제초제의 종류는 14종 17게 품목이고 이들중 8종 10개 품목은 일년생 잡초약 그리고 6종 7개품목은 소위 다년생 잡초약으로 분류되고 있다. 그동안 벼의 소출에 직접 영향을 주는 살충제나 살균제의 중요성에 비추어 제초제는 상대적으로 그 중요성이 비교적 경시(輕視)되어 온 것이 사실이다. 그러나 1980년 이후 일반농가는 물론 정부의 제초제에 대한 관심이 두드러지게 높아져서 여러 가지 논의가 되고 다각도에서 심각한 검토가 이루어지고 있는 것이 현실이다. 이 기회에 필자가 평소에 생각해온 문제의 핵심과 그 대책을 기술함으로써 효과적인 잡초방제에 일조(一助)가 되기를 바란다.

• Journal of the Korean Society of Safety
• /
• v.33 no.6
• /
• pp.8-14
• /
• 2018

Recently, serious problems occurred such as insecticide eggs, sanitary pads with carcinogens, radon(Rn) emitting beds in domestic. It had not been establishing the inspection system to evaluate safety and human harmfulness before occurring real accidents. This research was conducted to test preliminary experimental inspection for consideration of safety insensibility. The influence of corrosion of metals and plants was studied through aerosol type spraying of agricultural pesticide products coming into the market. These products contain primary three insecticide ingredients(Flufenoxuron, Etoxazole, Fipronil) in recent accidents. Visual examination, SEM-EDS and optical microscope were used for the analysis for corrosion effect. Results show that a lot of ingredients contain in the crop protection products, and various type of corrosion exist in the surface of metals and plants. Therefore, it is necessary to provide health warning and accurate range of use for crop protection products containing insecticide ingredients.

• The Korean Journal of Pesticide Science
• /
• v.17 no.4
• /
• pp.419-427
• /
• 2013

The insecticidal activity of 124 plant essential oils and control efficacy of six experimental spray formulations (SF) containing 0.25, 0.5, 1, 2.5, 5, and 10% of the selected oils was examined against both nymph and adult of the citrus flatid planthopper, Metcalfa pruinosa using direct contact applications (leaf dipping and spray). Reponses varied according to dose (1,000 and 500 mg/L). When exposed at 1,000 mg/L for 24 h using leaf dipping assay, 19 essential oils showed strong mortality (100%) among 124 essential oils screened. At 500 mg/L, 100% mortality was observed in cinnamon technical, cinnamon green leaf, cinnamon #500, cassia tree, citronella java and pennyroyal followed by origanum, thyme white, grapefruit, savory, fennel sweet, aniseed and cinnamon bark showed considerable mortality (93.3-80%) against nymphs of M. pruinosa. The moderate mortality (73.3-60%) was found in thyme red, tagetes, calamus, lemoneucalptus and geranium. Oils applied as SF-10% sprays provided 100 % mortality against adult M. pruinosa. One hundred mortalities were achieved in cinnamon technical at >SF-0.5 formulation, in cinnamon #500, cinnamon green leaf and penny royal at >SF-2.5. To reduce the level of highly toxic synthetic insecticides in the agricultural environment, the active essential oils as potential larvicides could be provided as an alternative to control M. pruinosa populations.

• Korean Journal of Environmental Agriculture
• /
• v.41 no.2
• /
• pp.125-134
• /
• 2022

BACKGROUND: It is a very important task to block distribution of the agricultural products contaminated with pesticides in advance to protect consumers from residual pesticides among the agricultural products. Therefore, this study was performed to determine residual characteristics of pesticides in time-dependent manner and present scientific evidences for pre-harvest residue limit (PHRL) setting. METHODS AND RESULTS: The tested pesticides, chromafenozide and pyridalyl were sprayed onto the kale twice (seven day intervals) and then the plant samples were collected at 0 (after 3 hours), 1, 2, 3, 5, 7, and 10 days after the last spraying. Residual concentration of chromafenozide in kale decreased with 74.9% (of decreased fraction, field 1) and 85.3% (field 2) and pyridalyl decreased with 81.2% (field 1) and 85.8% (field 2), calculated by comparisons of the concentrations at 0 day and 10 days. Also biological half-lives of chromafenozide in kale were 5.6 day (field 1) and 3.4 day (field 2), and those of pyridalyl were 4.3 day (field 1) and 3.5 day (field 2). CONCLUSION(S): If the residues of chromafenozide and pyridalyl in kale from 10 days before harvest are less than 37.6 mg/kg and 58.9 mg/kg, respectively, it is expected that safe kale below MRL can be supplied on the pre-harvest day.

• Journal of Applied Biological Chemistry
• /
• v.59 no.3
• /
• pp.243-245
• /
• 2016

The insecticidal toxicities of seven essential oils against Ricania sp. nymph and adults, newly recorded pest, were evaluated using leaf-dipping and spray methods. At 72 h exposure time, the $LC_{50}$ values of the essential oils of Artemisia vulgaris, Anethum graveolens, Citrus paradisi, Melaleuca alternifolia, Melaleuca leucadendron, Neroli bigarade and Tagetes erecta were 251.02, 387.31, 286.21, 353.54, 275.64, 424.55, $165.68mg/cm^2$ when using the leaf dipping method against Ricania sp. nymphs, and 278.31, 402.11, 306.11, 379.64, 298.22, 459.56, $183.21mg/cm^2$ when using the spray method against Ricania sp. adults, respectively. These results indicate that the essential oil of the Tagetes erecta can be potentially used as new natural insecticidal agents against Ricania sp. nymph and adults.

• Research in Plant Disease
• /
• v.23 no.3
• /
• pp.256-261
• /
• 2017

The effects of insecticide and fungicide treatment were investigated to reduce mycotoxin contamination of corn (Zea mays L.) seeds. Deoxynivalenol and zearalenone contents were reduced in the treated seeds, but aflatoxin, ochratoxin A, fumonisin, and T-2 toxin were not effective by chemical treatments. The chemical treatment did not affect the growth of saprophyte, but inhibited the pathogenic fungi such as Fusarium verticillioides, F. graminearum and F. equiseti. Myotoxin contents at different harvesting time were compared. As the harvest time was delayed, both levels of deoxynivalenol and zearalenone and frequency of Fusarium spp. increased. However, the major nutrient contents of corn seeds were not affected by harvesting period. These results show that chemical treatments are necessary to reduce the fungal contamination of corn and harvest without delay is important as well.