• Applied Biological Chemistry
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• v.48 no.1
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• pp.1-15
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• 2005

Pathogens, insects and weeds have significantly reduced agricultural productivity. Thus, to increase the productivity, synthetic agricultural chemicals have been overused. However, these synthetic compounds that are different from natural products cannot be broken down easily in natural systems, causing the destruction of soil quality and agricultural environments and the gradually difficulty in continuous agriculture. Now agriculture is faced with the various problems of minimizing the damage in agricultural environments, securing the safety of human health, while simultaneously increasing agricultural productivity. Meanwhile, plants produce secondary metabolites to protect themselves from external invaders and to secure their region for survival. Plants infected with pathogens produce antibiotics phytoalexin; monocotyledonous plants produce flavonoids and diterpenoids phytoalexins, and dicotylodoneous plant, despite of infected pathogens, produce family-specific phytoalexin such as flavonoids in Leguminosae, indole derivatives in Cruciferae, sesquitepenoids in Solanaceae, coumarins in Umbelliferae, making the plant resistant to specific pathogen. Growth inhibitor or antifeedant substances to insects are terpenoids pyrethrin, azadirachtin, limonin, cedrelanoid, toosendanin and fraxinellone/dictamnine, and terpenoid-alkaloid mixed compounds sesquiterpene pyridine and norditerpenoids, and azepine-, amide-, loline-, stemofoline-, pyrrolizidine-alkaloids and so on. Also plants produces the substances to inhibit other plant growths to secure the regions for plant itself, which is including terpenoids essential oil and sesquiterpene lactone, and additionally, benzoxazinoids, glucosinolate, quassinoid, cyanogenic glycoside, saponin, sorgolennone, juglone and lots of other different of secondary metabolites. Hence, phytoalexin, an antibiotic compound produced by plants infected with pathogens, can be employed for pathogen control. Terpenoids and alkaloids inhibiting insect growth can be utilized for insect control. Allelochemicals, a compound released from a certain plant to hinder the growth of other plants for their survival, can be also used directly as a herbicides for weed control as well. Therefore, the use of the natural secondary metabolites for pest control might be one of the alternatives for environmentally friendly agriculture. However, the natural substances are destroyed easily causing low the pest-control efficacy, and also there is the limitation to producing the substances using plant cell. In the future, effects should be made to try to find the secondary metabolites with good pest-control effect and no harmful to human health. Also the biosynthetic pathways of secondary metabolites have to be elucidated continuously, and the metabolic engineering should be applied to improve transgenics having the resistance to specific pest.

• Plant Biotechnology Reports
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• v.5 no.3
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• pp.217-224
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• 2011

Non-heading Chinese cabbage (Brassica rapa L. ssp. chinensis) is a popular vegetable in Asian countries. The diamondback moth (DBM), Plutella xylostella (L.), an insect with worldwide distribution, is a main pest of Brassicaceae crops and causes enormous crop losses. Transfer of the anti-insect gene into the plant genome by transgenic technology and subsequent breeding of insect-resistant varieties will be an effective approach to reducing the damage caused by this pest. We have produced transgenic non-heading Chinese cabbage plants expressing the potato proteinase inhibitor II gene (pinII) and tested the pest resistance of these transgenic plants. Non-heading Chinese cabbages grown for 45 days on which buds had formed were used as experimental materials for Agrobacterium-mediated vacuum infiltration transformation. Forty-one resistant plants were selected from 1166 g of seed harvested from the infiltrated plants based on the resistance of the young seedlings to the herbicide Basta. The transgenic traits were further confirmed by the Chlorophenol red test, PCR, and genomic Southern blotting. The results showed that the bar and pinII genes were co-integrated into the resistant plant genome. A bioassay of insect resistance in the second generation of individual lines of the transgenic plants showed that DBM larvae fed on transgenic leaves were severely stunted and had a higher mortality than those fed on the wild-type leaves.

• Korean journal of applied entomology
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• v.59 no.1
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• pp.55-64
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• 2020

Smart greenhouses are primarily used for growing fruits and vegetables, such as sweet peppers, tomatoes, strawberries. Although the number of smart greenhouses has been increasing exponentially, no studies have been performed to evaluate the state of smart greenhouses in Korea. Therefore, this study was conducted to determine current state of smart greenhouses with regard to greenhouse specifications, crop growing methods, pests, and user satisfaction in Korea. Contact information for smart greenhouses was provided by the officials of local agricultural research and extension services. This survey was conducted by visiting each greenhouse. Results showed that approximately 50% of surveyed smart greenhouses were between 3,300 ㎡ and 6,600 ㎡. The most frequently chosen method for pest control was chemical pesticides (97.1%). Powdery mildew and gray mold comprised 54.4% and 33.8% of the crop diseases, respectively. All tomato greenhouse farmers considered whiteflies the most problematic pest. In contrast, 76.5% and 70.6% of sweet pepper farmers believed thrips and aphids posed significant threats, respectively. The mean satisfaction score was 7.5 out of 10 points, with 10 being "extremely satisfied". These results will aid in decision making with respect to the management of current smart greenhouses and the design of future smart farms in Korea.

• Journal of Applied Biological Chemistry
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• v.61 no.3
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• pp.291-295
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• 2018

Metcalfa pruinosa is a pest causing widespread problems to many crops in Korea. This pest infects fruit crops especially, persimmon and grapes. We tested the possibility of M. pruinosa management using essential oils of Alpina galangal and methylcinnamate which were extracted from A. galangal by steam distillation method. The use of essential oil showed a mortality rate of 10.0 and 23.3% for adults and nymphs, respectively. While the use of methylcinnamate resulted to a mortality rate of 40.0% in adults and 36.6% in nymphs. For its repellent effect, it showed an avoidance rate of 50.0 and 63.3% for adult and nymph respectively. Considering these two results, the extract of A. galangal are shown to have some synergic effect for pest control. The result of this study showed a possibility of M. pruinosa control using essential oil and methylcinnamate from A. galangal.

• Journal of Korean Society of Rural Planning
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• v.16 no.4
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• pp.139-145
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• 2010

Agricultural information was discussed for suggesting tasks and solutions of knowledge based information system. States of agricultural information systems in rural development administration were described and problems and tasks were summarized in knowledge needs survey of farmers who have to decide many alternatives for farming. Hard to access information are soil state, disease and insect pest. Important information in agriculture are water, soil fertility, soil physical property, and accessibility from main road. In conclusion, knowledge based agricultural information system can be developed based on surveyed needs.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.259-262
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• 2011

In organic Chinese cabbage fields, Commercial Bacillus thuringiensis products are used widely against diamond back moth, Plutella xylostella. We conducted the study to determine the effective spray-interval of commercialized B. thuringiensis against diamond back moth on Chinese cabbages. Chinese cabbage leaves were collected 0, 1, 2, 3, 6, 10days after treatment in first trial and 0, 2, 4, 7, 9, 11days after treatment. We compared the insecticidal property of sprayed B. thuringiensis and the density of it on surface of Chinese cabbages using collected leaves. The insecticidal property maintained high until nine days after commercial B. thuringiensis products sprayed.

• Journal of Applied Biological Chemistry
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• v.57 no.3
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• pp.243-245
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• 2014

To evaluate light-emitting diode (LED) as potential attractants for Bemisia tabaci adults, attractiveness of white and yellow LED traps were investigated in greenhouse. The yellow LED trap showed the most attractive to B. tabaci adults, followed by a similarly attraction to the white LED trap, whereas the control (no light trap) was little attractive to B. tabaci adults. These results suggested that yellow and white LED traps could be used for environment-friendly insect pest control.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.360-366
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• 2011

Bacterial leaf spot of Euphorbia pulcherrima has been reported in many countries. Characterization by polyphasic approaches indicated that the isolates from India, USA and New Zealand could be distinguished based on rep-PCR profiles and gyrB phylogenies, while the Chinese isolates should be ascribed to Xanthomonas axonopodis pv. poinsettiicola.

• Korean journal of applied entomology
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• v.62 no.4
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• pp.221-225
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• 2023

A female specimen of Sternuchopsis (s. str.) waltoni (Boheman, 1844), belonging to the tribe Mecysolobini (Curculionidae: Molytinae), was collected by beating method from Gadeok-do in Busan, the southern part of the Korean Peninsula. This weevil pest is designated as a quarantine pest under the Plant Quarantine Act (2019) in Korea. It is considered unreasonable to determine whether this species is an invasive or native species in Korea, as damage to crops has not been confirmed and there is no other collection information. This study aims to provide accurate diagnosis information including illustration and ecological information to gain more domestic occurrence information on this weevil.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.414-420
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• 2008

To investigate the actual condition of orchard and pest management of persimmon orchards, a questionnaire was ask to the farmers in major cultivated areas of persimmon and dried persimmon, Sangju, Gyeongbuk in 2007 and 2008. 91.1% of persimmon farmers was over fifties in age and 94.7% of persimmon farmers was cultivated 'Sangjudungshi'. The greatest limiting factor for persimmon production was thought to be disease by the 58.4% of persimmon farmers and the most serious disease was anthracnose by Colletotrichum gloeosporioides. 60.2% of them was answered that the most serious insect pest was scale insects. Obtaining of knowledge or information on pest management depended own experience (37.2%) and 48.7% of answered farmers was decision-marking of pesticides depending on agrochemical market. 54% of persimmon farmers was applied pesticides $3{\sim}5$ times per year. Just 17.7% of them recorded the diary of pesticide application. The greatest problem for management of pest in persimmon orchard was lack of knowledge of pest (60.2%) and farmers considered increasing cost for pest management as the greatest problem with 52.2% in proportion. 66.4% of farmers was mixed cultivation with soybean (37.7%) and hot pepper (26.1%) in persimmon orchard. 44.2% among answered farmers mixed cultivation of persimmon with production of dried persimmon and 54.5% of farmers considered lack of labor as the greatest problem in production of dried persimmon.