• Korean Journal of Weed Science
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• v.13 no.2
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• pp.151-158
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• 1993

This experiment was conducted in order to understand the intra-and the inter-competition of arrowhead, Sagittaria trifolia L., under the conditions of arrowhead monoculture and rice-mixed culture, respectively. In arrowhead monoculture, the infra-specific competition in both shoot length and floral axis number began at 10 plants per $0.5m^2$ and that in leaf number, leaf length, dry shoot weight and formated tuber number did at 5 plants per $0.5m^2$. In the inter-specific competition according to arrowhead density in the constant rice-mixed culture, the plant height and the tiller number of rice decreased at 15 and 5 plants of arrowhead per $0.5m^2$, respectively. The dry top weight and the formated tuber number of arrowhead decreased with increase of arrowhead density. In the inter-competition according to rice plant density in the constant arrowhead-mixed stands, the dry matter weight and the produced tuber number of arrowhead decreased with increase of rice plant density and the plant height and the tiller number of rice also did with that. In the different transplantation time of rice, the growth in arrowhead became less in order of late transplantation>standard one>early one and the plant height and the tiller number of rice became more in order of that by comparing the percentage of growth under the mixed culture to that under the arrowhead monoculture.

• 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.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.86-94
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• 2002

Recently a serious outbreak of weed mould caused by a species of Hypocrea occurred in oyster mushroom (Pleurotus ostreatus) substrates in Korea. The disease was characterized by a rapid infestation of the oyster mushroom substrates by Hypocrea sp. and subsequent inhibition of fructification of the mushroom. In spite of it's serious losses to the oyster mushroom industry in Korea, etiology and ecology of the disease have not been studied. Morphological characteristics of the fungus were examined and molecular characteristics of the fungus were compared with those of the green moulds (Trichoderma spp.) isolated from oyster mushroom bed. Stromata formed superficially on suface of the substrates were pulvinate to effuse or irreguler, initially white but becoming yellowish brown, measuring $6.0{\sim}13.0{\times}3.0{\sim}11.0mm$. Perithecia were globose to subglobose, immersed in stroma, $223{\sim}263\;(Ave.239.9){\times}167.3{\sim}231\;(Ave.204.1){\mu}m$ in size. Asci were unitunicate, cylindrical, nonamyloid, $82.7{\sim}124.8\;(Ave.103.3){\times}4.1{\sim}5.1\;(Ave.4.9){\mu}m$ in size, 16 part-spored. Ascospores were bullet-shaped or somewhat oblong, hyaline, bicellular, roughened or warted, $5.4{\sim}7.4\;(Ave.6.5){\times}3.6{\sim}5.5\;(Ave.4.7){\mu}m$ in size. This fungus readily form the stroma on PDA. Mycelia on PDA nearly invisible and without cottony aerial mycelium. Optimum temperature for mycelial growth of this fungus was $25^{\circ}C$ on PDA and its growth rate was 15 mm per day. This species did not grow at below 10 and above $35^{\circ}C$. Phialides in culture enlarged in the middle and aggregated to penicillate type. They were very variable, shorted ampulliform and occasionally curved when matured, but cylinderical when young, measuring $11.9{\sim}24.3\;(Ave.\;14.7){\times}2.9{\sim}3.9\;(Ave.\;3.4){\mu}m$ when matured and $7.2{\sim}14.0\;(Ave.\;10.8){\times}2.8{\sim}4.9\;(Ave.\;3.5){\mu}m$ when young. Phialosopres were ovoid to ellipsoid, smooth, measuring $3.5{\sim}7.2\;(Ave.\;4.5){\times}2.6{\sim}3.3\;(Ave.\;2.9){\mu}m$. Nineteen isolates of Hypocrea sp. were analyzed on the basis of molecular characteristics and classified into phenotypic groups. On the basis of RAPD, URP-PCR, the fungus was confirm to monoclonal, and was classified as a different taxon from reported species of Hypocrea and Trichoderma and supposed to be a new species not previously reported in literature.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.138-150
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• 1993

Experiments were carried out to understand how much do the environmental factors affect growth and tuber formation of arrowhead, Sagittaria trifolia L. The more the light transmittance decreased, the more the numbers of leaves and floral axes decreased. The dry matter weight of tops and the number and the fresh weight of formated tuber were significantly different between the light transmittance of more than 50% and that of less than 30% at the 5% level of DMRT. Plant height, number and width of leaves, and number of floral axis were affected by the Light spectra. And the degree of their effects on growth of arrowhead was different form the light spectrum. The natural light and the clear cellophane film were the most effective to increase the number and the fresh weight of formated tuber and the green spectrum was the least effective to do those. Plant height grown at 0-5cm water depth was shorter than that at 10-20cm water depth. The deeper the water depth was, the lower the leaves number was. The fresh weight and the number of arrowhead tuber were most produced at 0cm water depth and theose were least at 20cm water depth. The shoot growth and the tuber formation of arrowhead was much increased with increase of the application rate of fertilizer. The difference of the transplanted tuber size was not affected at the shoot growth, but tuber formation of arrowhead was increased with increase of the transplanted tuber size. From viewing the effect of temperature after rice heading, the shoot growth and the tuber formation at $35^{\circ}C$ were also higher than those at $25^{\circ}C$.

• Korean Journal of Weed Science
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• v.12 no.2
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• pp.124-131
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• 1992

Not only reducing the carry-over effects of quinclorac [3, 7-dichloro-8-quinoline carboxylic acid] used in paddy field to some following vegetable crops but also rationalizing agro-ecology conservation and farm economy, the reducing feasibility of application rates by various cropping patterns and application timing after rice seeding and transplanting. Four cropping patterns namely dry direct seeding(DDS), flooded direct seed(FDS), transplanting of 8 days old early seedlings(EST) and 25 days old machinery seedling(MST) were experimented with 7 application timings as 0, 5, 10, 15, 20, 25, 30 days after seeding/transplanting and 9 levels of application rates as 0, 75, 150, 225, 300, 375, 450, 525, and 600g ai/ha of the chemical, respectively. Within the maximum permitted limit of rice phytotoxicity, the minimum application rate of quinclorac to complete control of Echinochloa crus-galli as influenced by various cropping patterns with application timing could be evaluated as follows : A. Dry direct seeding : The minimized application rate at application timing upto 10 days after seeding (DAS) was counted 150g ai/ha, and delaying upto 15-30 DAS, the rates were increased upto 225-525g ai/ha. B. Flooded direct seeding and transplanting : The application rates were minimized 75g ai/ha at application timing upto 10 days after seeding/transplanting(DAS/T), 150g ai/haupto 15 DAS/T, and 225g ai/ha at later than 20 DAS/T, respectively.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.4
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• pp.211-221
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• 2021

The Rabbit grass(Trifolium Repens, call it 'Clover') is a representative harmful plant of lawn, and it starts growing earlier than lawn, forming a water pipe on top of the lawn and hindering the photosynthesis and growth of the lawn. As a result, in competition between lawn and clover, clover territory spreads, but lawn is damaged and dried up. Damage to the affected lawn area will accelerate during the rainy season as well as during the plant's rear stage, spreading the area where soil is exposed. Therefore, the restoration of damaged lawn is causing psychological stress and a lot of economic burden. The purpose of this study is to distinguish clover which is a representative harmful plant on lawn, to identify the distribution of damaged areas due to the spread of clover, and to review of changes in vegetation before and after the eradication of clover. For this purpose, a time series analysis of three vegetation indices calculated based on images of convergence Drone with RGB(Red Green Blue) and BG-NIR(Near Infra Red)sensors was reviewed to identify the separation between lawn and clover for selective eradication, and the distribution of damaged lawn for recovery plan. In particular, examined timeseries changes in the ecology of clover before and after the weed-whacking by manual and brush cutter. And also, the method of distinguishing lawn from clover was explored during the mid-year period of growth of the two plants. This study shows that the time series analysis of the MGRVI(Modified Green-Red Vegetation Index), NDVI(Normalized Difference Vegetation Index), and MSAVI(Modified Soil Adjusted Vegetation Index) indices of drone-based RGB and BG-NIR images according to the growth characteristics between lawn and clover can confirm the availability of change trends after lawn damage and clover eradication.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.535-542
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• 2012

This study was carried out from 2011 to 2012 in order to analyze the cultivation technology system by six organic rice cultivation types in the southern provinces for the purpose of utilizing organic rice farming guidelines. This surveys were conducted by site visit on 8 counties and 115 farms in southern area. Cultivation technology system by six organic rice cultivation types were cultivated by the principle of minimum input or non-input. cropping systems, a mixture of barley and rice, or rice green manure crops were grown. Cultivars were mixture of the local cultivars and Japanese varieties. Soil were managed by a self-manufactured compost, indigenous microorganisms and barley straw without any fertilization. Pest control was mainly practied by purchased eco-friendly organic materials or herbal medication residue and indigenous microbial self-manufactured. Weed was controled by snails and barley straw. In addition, considering the restore of a longtail pitching shrimp and grasshoppers, the fuction of environmental ecology of six organic rice cultivation type proved to be excellent all. Meanwhile, the productivity of the organic farming per 10a were the order of Life and environment > Natural circulation > Stevia > Ji jang > Art and nature > Taepyoung of Farming Methods, but the farmers received prices showed the opposite tendency. Simple profitablity did not show a big difference. But, the productivity of all type of the organic farming were lower then the conventional farming. Finally, If we want to conduct safety and easy farming, we can suggest stevia farming, Natural circulation farming and life and environmental farming out of 6 organic rice cultivation types.