• Korean journal of applied entomology
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• v.31 no.3
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• pp.205-240
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• 1992

In reality, it is a green revolution of the entire agricultural matrix in Korea that integrated pest control plays an important role in the possible breakthrough in rice self-sufficiency. In paddy agroecosystem as man-modified environment, rice is newly established every year by transplantation under diverse water regimes which affect a microclimate. Standing water benefits rice by regulating the microclimate, but it favors the multiplication of certain pets through the amelioration of the microclimate. Further, the introduction of high yielding varieties with the changing of cultural practices results in changing occurrence pattern of certain pests. In general, japonica type varieties lack genes resistant to most of the important pests and insect-borne virus diseases, whereas indica type possesses more genes conferring varietal resistance. Thus, this differences among indica type, form the background of different approaches to pest management. The changes in rice cultivation such as double cropping, growing high-yielding varieties requiring heavy fertilization, earlier transplanting, intensvie-spacing transplanting, and intensive pesticide use as a consequence of the adoption of improves rice production technology, have intensified the pest problems rather than reduced them. The cultivation of resistant varieties are highly effective to the pest, their long term stability is threathened because of the development of new biotypes which can detroy these varieties. So far, three biotypes of N. lugens are reported in Korea. Since each resistant variety is expected to maintain several years the sequential release of another new variety with a different gene at intervals is practised as a gene rotation program. Another approach, breeding multilines that have more than two genes for resistance in a variety are successfully demonstrated. The average annual rice losses during the last 15 years of 1977-’91 are 9.3% due to insect pests without chemical control undertaken, wehreas there is a average 2.4% despite farmers’insecticide application at the same period. In other words, the average annual losses are prvented by 6.9% when chemical control is properly employed. However, the continuous use of a same group of insecticides is followed by the development of pest resistance. Resistant development of C. suppressalis, L. striatellus and N. cincticeps is observed to organophosphorous insecticides by the mid-1960s, and to carbamates by the early 1970s in various parts of the country. Thus, it is apparent that a scheduled chemical control for rice production systems becomes uneconomical and that a reduction in energy input without impairing the rice yield, is necessarily improved through the implementation of integrated pest management systems. Nationwide pest forecasting system conducted by the government organization is a unique network of investigation for purpose of making pest control timely in terms of economic thresholds. A wise plant protection is expected to establish pest management systems in appropriate integration of resistant varieties, biological agents, cultural practices and other measures in harmony with minimizing use of chemical applications as a last weapon relying on economic thresholds.

• Korean journal of applied entomology
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• v.41 no.2
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• pp.129-136
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• 2002

Agamermis unka, a mermithid parasite of brown planthopper (BPH), Nilaparvata lugens, is the most important natural enemy of BPH and white-backed planthopper (WBPH), Sogatella furcifera in Korea. Distribution of A. unka was investigated in Korean rice fields from 1992 to 1998 and in 2001. Overwintering population of A. unka in Gosung, Namhae, and Tongyoung from 1992 to 1998 was different depending on locality and year. In the survey of A. tanka distribution in the spring of 2001, A. unka was found only at Jangheung and Haenam in Jeonnam province and Namhae, Jinju, Sancheong, Sacheon, Gosung, Tongyoung, Uiryeong, Changwon, Gimhae, and the experimental field of Gyeongsangnamdo Agricultural Research and Extension Services at Jinju in Gyeongnam province out of 30 observed regions in 5 provinces. The number of A. unka was 1,045/㎥ at Namhae, 947/㎥ at the experimental field of Gyeongsangnamdo Agricultural Research and Extension Services, and 395/㎥ at Gosung. Density of A. unka at the rice paddies of Gyeongnam province after harvest in 2001 was higher at the rice fields of Namhae, Gosung, and the experimental field of Gyeongsangnamdo Agricultural Research and Extension Services. Although density of A. unka was higher in the pesticide-untreated plots than fungicide-treated or insecticide-treated plots of forecasting paddies, there were no significant differences. After rice harvest A. unka was found from the forecasting paddies of Gosung, Jinju, Namhae and Sacheon out of 19 observed localities in Gyeongnam province.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.437-443
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• 1995

Concerns on use of excess amount of chemical fertilizier and pesticide in current farming system turns both of the producer and consumer of agricultural products to an organic farming which use a less chemicals and more natural manure. Rice-duck farming system is one of the strategy to meet the purpose and this experiment was carried out to find the effect of the rice-duck farming system on the quality and yields of rice. 20day-old rice seedling were mechanically transplanted in sandy-loam paddy field and 21 day-old ducks were raised from 3 weeks after transplanting with population of 30 heads per 10a. The plots were consists of reduce fertilizer(70%) with and without duck-raising. The conventional fertilizer treatment without duck-raising was used as check. The results obtained are summarized as follows. The weeds population of test plots which were raised with duck for 3 consecutive years was less than that of test plots without duck-raising, though a speciffic population of Echinochola crusgallis were increased. The weed control effect was higer in duck-raising than in check at the maximum tillering stage but, not at later stages of rice plant. It was found that the small animals and insects inhibiting in the rice field were reduced by duck-treatment, however, there were also damages of grass leaf roller at booting stage in the plots of duck-raising. In rice-duck plot, dark green leaf color were found: 41.8 of SPAD value than 38.6 of SPAD in check plot. Higher root activity and surface soil oxidation were also observed in rice-duck plot than check plot. 3% of the increase in yield was observed by duck-treatment. However, the expected increase of the palatability wsa not observed. This may be due to the unfavorable weather conditions during the rice growing in this expriment.

• Research in Plant Disease
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• v.24 no.1
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• pp.9-25
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• 2018

Plant viruses cause significant yield losses and continuously threaten crop production, representing a serious threat to global food security. Studies on plant-virus interactions have contributed to increase our knowledge on plant immunity mechanism, providing new strategies for crop improvement. The prophylactic managements consist mainly following international legislations, eradication of infected plants, and application of pesticide to decrease the population of vectors. Hence, putting together the pieces of knowledge related to molecular plant immunity to viruses is critical for the control of virus disease in fields. Over the last several decades, the outstanding outcomes of extensive research have been achieved on comprehension of plant immunity to viruses. Although most dominant R genes have been used as natural resistance genes, recessive resistance genes have been deployed in several crops as another efficient strategy to control viruses. In addition, RNA interference also regulates plant immunity and contribute a very efficient antiviral system at the nucleic acid level. This review aims at describing virus disease on crops and summarizes current resistance mechanisms. Furthermore, we will discuss the current biotechnological approaches to control viral diseases and the future questions that are to be addressed to secure crop production against viruses.

• Research in Plant Disease
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• v.26 no.2
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• pp.103-108
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• 2020

Evaluations were made for the effects of cheese whey treatment on infection of pepper plants by cucumber mosaic virus-Vch (CMV-Vch) and pepper mottle virus-Kr (PepMoV-Kr). In a greenhouse, pepper plants sprayed with whey, prior to inoculation by CMV-Vch using aphids, showed a viral infection rate significantly lower (6.6%) than for the control (23.3%). In an open field experiment, in which CMV infection relied on natural transmission by aphids, pepper plants were sprayed with undiluted whey once a week, starting on the transplanting date (May 2) to the end of June. On June 5, these whey-sprayed plants showed a CMV infection rate reduced by 18.9% and 16.7%, compared to untreated and pesticide-treated plants, respectively. In the greenhouse, pepper plants inoculated with PepMoV-Kr mixed with whey showed a viral infection rate decreased by 60% compared to the control. The accumulated amount of PepMoV-Kr coat protein was less than that for the virus-only control at 6 days post inoculation (dpi), but increased up to a similar level as the control at 9 dpi. This study showed that cheese whey is effective in reducing infection of both CMV and PepMoV in pepper plants.

• The Journal of Korean Medicine
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• v.30 no.4
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• pp.118-128
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• 2009

Objects: This study was conducted to investigate the current educational environment of herbology and to develop a future-oriented curriculum for oriental medicine. The questionnaire used in this research was drawn up based on the current curriculum referring to the current curriculum of herbology and pharmacognosy. Methods: The survey was carried out presenting the questionnaires to a total 12,754 of the students and doctors of oriental medicine through e-mailing five times; of these, 2,074 replied. Results: 1. Among the respondents, about 97% agreed that it was necessary to revise and complement the current curriculum of herbology. 2. The respondents felt that the assigned lecture time of subject was "sufficient" (19%), "insufficient" (39%) and "average" (39%), respectively, and the level of lecture was "insufficient" (37%) or "average" (43%) respectively. According to priority, it showed that the contents which needed complement in lecture were discrimination of medicinal herbs (24%), practical use of action and indications (23%), and correlation with modern disease (21%). In theoretical lectures, 69% of the respondents agreed on the introduction of natural scientific methods 3. In practice, 51% of the respondents replied that the lecture time for practice was insufficient. The contents which needed to be complemented in practice were as follows: audio-visual materials for discrimination of medicinal herbs (22%), concrete exercise for the processing of medicinal herbs (21%), and attempts for the objective discrimination of medicinal herbs using instruments (microscope, analytical instrument, residual pesticide, heavy metal, genetic analysis) (16%). 70% replied that the discrimination of medicinal herbs of high price and rarity was "none or insufficient". 4. 56% replied that it was necessary to introduce and practice physicochemical analysis, and they showed higher requests according to the increase of their educational level. However, 86% replied that they had never experienced concrete attempts for objective discrimination of medicinal herbs, which seemed to indicate that, excepting some schools, practice exercise was rarely performed. Conclusions: According to results, it seems that an urgent review on the current course of herbology and a workshop on the process of experimental practice for professors is needed.

• Journal of Soil and Groundwater Environment
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• v.11 no.6
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• pp.43-52
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• 2006

Effectiveness of activated soil containing directly enriched atrazine-degrading soil microorganisms as an inoculant to bioaugment degradation of atrazine in soils was investigated. A Wooster silt loam (Typic Fragiudalf) was spiked with atrazine at a rate of 4 mg/kg soil three successive times to create activated soil. Atrazine degradation was significantly enhanced (p < 0.05) after the first treatment. After the second treatment, there was an increase in the number, based on MPN, of microorganisms utilizing atrazine as a C- and N-source by 3 logs and 1 log of magnitude, respectively. Inoculation of typical agricultural soils collected from Ohio with activated soil at a rate as low as 0.5% reduced the extractable atrazine remaining in soils to the level below 2% of that initially recovered (initially added at a rate of 4 mg/kg soil) after 4 days. Inoculation at a higher rate was required to achieve the same result in soils with non-typical properties (pH of 4.5 or organic matter of 43% w/w). Activated soil was stable, in terms of atrazine degradation activity, at least up to 6 months when it was kept at low temperature (< $10^{\circ}C$) and moistened (water content above 15%). The results of this study indicate that microorganisms capable of degrading atrazine are relatively easily enriched in soil to create activated soil. Use of activated soil can be a practical option for bioremediation of contaminated soils.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.260-269
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• 2021

BACKGROUND: Diquat dibromide is a fast-acting nonselective herbicide and plant growth regulator. In this study, in order to understand the possibility of unintentional pesticide contamination in the following crops, the phytotoxicity and transition of diquat dibromide residue in soil into the following crops such as pepper, radish, lettuce and corn have been assessed through phytotoxicity trial and residual evaluation in the unintentional contamination of the higher residual diquat dibromide. METHODS AND RESULTS: The pepper, radish, lettuce and corn were cultivated in the sandy soil and loam soil where the 35 mg/kg and 90 mg/kg diquat dibromide were applied, respectively. Mild growth inhibition symptoms were observed in radish, lettuce and corn crops at the 90 mg/kg- diquat dibromide treatment on the 30 day of cultivation. Diquat dibromide was analyzed using liquid chromatography QTRAP (LC-MS/MS). The recovery rates of diquat dibromide from soil and crop were determined within range from 89.1 to 116.4% with relative standard deviation less than 14.7%. Diquat dibromide residues in soil were found to be 23.90-30.22 and 69.59-82.57 mg/kg from the 35 mg/kg and 90 mg/kg of diquat dibromide-treated soil, respectively after 30 days of crop cultivation. This result implicates that diquat dibromide did not convert to metabolites and remained mostly in the soil, even though it was partially decomposed during crop cultivation. In addition, the diquat dibromide in pepper and radish that were grown for 47 days, and lettuce and corn that were cultivated for 30 days were detected to be 0.01 mg/kg or less in the sandy loam and loam soil where the 90 mg/kg diquat dibromide was applied. CONCLUSION(S): Diquat dibromide did not cause severe phytotoxicity in the following crops as well as it did not uptake and distribute to the following crops, even though it was considered to be residual in the soil.

• Korean journal of applied entomology
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• v.58 no.3
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• pp.233-238
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• 2019

For greenhouse crops, thrips is one of the major insect pests, but its control is difficult owing to short generation time, rapid escaping behavior, and development of pesticide resistance. Stratiolaelaps scimitus (Womersley) is a soil-dwelling predatory mite attacking various soil invertebrate species, including thrips. Using the method by growers' self-production, we mass-reared S. scimitus colony and investigated thrips control in the greenhouse chrysanthemum. The initial density of thrips was six individuals/flower. The treatment with one S. scimitus box in the greenhouse was estimated to be $1,000individuals/m^2$. From August to September 2018, the greenhouse was released with a total of 10 boxes of S. scimitus. The density of thrips in the untreated and the treated cultivar was $53.7{\pm}7.0$ and $13.5{\pm}1.7$ on the late September, respectively, which indicated a reduction of 74.9% in the treated cultivar. Our results suggest that S. scimitus was highly effective for the control of thrips in the greenhouse chrysanthemum although temperature is very high during the summer season.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.171-190
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• 2012

The Korean Society of Applied Entomology (KSAE) celebrates its First 50 years history this year, 2011. It began in the year 1962, as the Korean Society of Plant Protection (KSPP) to discuss all aspects of plant protection including entomology and plant pathology. At that time it was one of the earliest scientific ones among agricultural societies in Korea. Before liberation from the Japanese colonial rule there were a few scientific societies for Japanese scientists only in the Korean Peninsula. It seemed that there was a single exception, in medical field, formed by and operated for Korean ethnics. Right after the liberation, Korean scientists rushed to form new scientific societies in the fields of mechanical engineering, architecture, textile, internal medicine, biology, etc. in 1945, mathematics, chemistry, metallurgy, etc. in 1946, and so on. But agricultural scientists had to wait for more time before setting up their own scientific society, Korean Agricultural Society(韓國農學會), comprising all agricultural subfields, in 1954. They had annual meetings and published their own journal every year until 1962. Then those working in the plant protection field established their own KSPP, right after their section meeting in 1962. At that time the total number of participants for KSPP were only around 50. KSPP scientists were interested in plant pathology, agricultural chemicals, weed science, or bioclimate, besides entomology. They had annual meetings once or twice a year until 1987 and published their own journal, Korean Journal of Plant Protection (KJPP), once a year at the earlier years but soon gradually increasing the frequency to four times a year later. Articles on entomology and plant pathology occupied about 40% each, but the number of oral or posters were a little bit higher on plant pathology than entomology, with the rest on nematology, agricultural chemicals, or soil microarthropods. There also had a number of symposia and special lectures. The presidentship lasted for two years and most of president served only one term, except for the first two. The current president should be $28^{th}$. In the year 1988, KSPP had to be transformed into the applied entomology society, Korean Society of Applied Entomology (KSAE), because most of plant pathologists participating left the society to set up their own one, Korean Society of Plant Pathology in 1984. Since that time the Society concentrates on entomology, basic and applied, with some notes on nematology, acarology, soil microarthropods, agricultural chemicals, etc. The Society has been hosting annual meetings at least twice a year with special lectures and symposia, from time to time, on various topics. It also hosted international symposia including binational scientific meetings twice with two different Japanese (applied entomology in 2003 and acarology in 2009) societies and the Asia-Pacific Congress of Entomology in 2005. The regular society meeting of this year, 2011, turns out to be the 43rd and this autumn non-regular meeting would be the 42nd. It has been publishing two different scientific journals, Korean Journal of Applied Entomology (KJAE) since 1988 and the Journal of Asia-Pacific Entomology (JAPE) since 1998. Both journals are published 4 times a year, with articles written in Korean or English in the first, but those in English only in the latter with cooperation from the Taiwan Entomological Society and the Malaysian Plant Protection Society since 2008. It is now enlisted as one of those SCI(science citation index) extended. The highest number of topics discussed at their annual meetings was on ecology, behavior, and host resistance. But at the annual meetings jointly with the Korean Society of Entomology, members were more interested in basic aspects, instead of applied aspects, such as physiology and molecular biology fields. Among those societies related to entomology and plant protection, plant pathology, pesticide, and applied entomology societies are almost similar in membership, but entomology and plant pathology societies are publishing more number of articles than any others. The Society is running beautifully, but there are a few points to be made for further improvement. First, the articles or posters should be correctly categorized on the journals or proceedings. It may be a good idea to ask members to give their own version of correct category for their submissions, either oral or poster or written publication. The category should be classified detailed as much as possible (one kind of example would be systematics, morphology, evolution, ecology, behavior, host preference or resistance, physiology, anatomy, chemical ecology, molecular biology, pathology, chemical control, insecticides, insecticide resistance, biocontrol, biorational control, natural enemies, agricultural pest, forest pest, medical pest, etc.) and such scheme should be given to members beforehand. The members should give one or two, first and second, choices when submitting, if they want. Then the categories might be combined or grouped during editing for optimal arrangement for journals or proceedings. Secondly the journals should carry complete content of the particular year and author index at the last issue of that year. I would also like to have other information, such as awards and awardees in handy way. I could not find any document for listing awards. Such information or article categorization may be assigned to one of the vice presidents. I would rather strongly recommend that the society should give more time and energy on archive management to keep better and more correct history records.