• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.341-347
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• 2009

Soil microbial community has been changed after the treatment of anaerobic fermentation using wheat bran or rice bran was applied to the soil. In the dilution plate technique, the number of anaerobic bacteria and fungi was higher in rice bran-treated soil than in non and wheat bran-treated soil, but of yeast was higher in wheat bran-treated soil than in non and rice bran-treated soil. Specially, the fungi were not detected in the wheat bran-treated soil. Identified by 16S rDNA sequencing, the number of aerobic bacteria was similar in all treatments, the dominant bacteria was the genus Bacillus. In the phospholipid fatty acid (PLFA) technique, both Gram-positive and Gram-negative bacteria change slightly in all treatments for 20 days of fermentation process but, after 20day, increased rapidly in wheat or rice bran-treated soil. In conclusion, the microbial communities structure was dramatically changed after the treatment of wheat or rice bran to soil.

• The Korean Journal of Mycology
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• v.26 no.3 s.86
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• pp.293-301
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• 1998

Taxonomical studies of soil-borne fungi were performed. Soil samples were collected from greenhouses located in Jinju-City, Korea. Soil dilution plating method was adopted for the pure isolation. Seven ascomycetous fungi were isolated from the soil samples, and subsequently identified. Among them, five isolates, Chaetomium brasiliense, C. indicum, Corynascus sepedonium, Petriella sordida, and Thielavia fragilis have never been reported in Korea. Both teleomorphic and anamorphic states were observed in the two species, Corynascus sepedonium and Petriella sordida, and only teleomorphic state was observed in Thielavia fragilis, Chaetomium indicum, and Chaetomium brasiliense. Illustrated descriptions are presented for the isolates examined in the present study.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.280-287
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• 1997

This study was carried out to investigate agricultural status and soil fertility of Bonghwang-cheon watershed area which is located at Chodong-myeon, Milyang-si. The acreage of arable land was about 1,209ha, and the population was 3,706 people. Out of total arable land, paddy was 64.4%, upland 19.6% and orchard 16.0%. Chicken was the largest in the number of livestock and poultry, but pig seems to contribute most severly to water pollution. The geology in the lower stream was alluvium but andesite and derivated materials from it were occupied most upland areas. Tuff was scattered in the small area near by the alluvium of Nakdong river, and diorite and granodiorite were located at the low hill and mountains respectivately. The principal paddy soils in the area were Geumgog, Jisan and Imgog series etc of fine loamy on sloped valleys and fans. The Pyeongtaeg series, fine silty family of imperfectly drained on plain was irrigated by Chodong reservoir. The clayey Honam series on alluvium was distributed along the low hill while Gyuam series, coarse silty alluvial soil way close to Nakdong river. In chemical properties of soils, the vinyl house soils were higher in EC, and orchard soils in OM, $P_2O_5$, exchangeable canons than other soils.

• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.335-343
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• 2006

Five strains of Korean entomopathogenic nematodes(EPN), steinernematids and heterorhabditids(Steinernama carpocapsae GSN1, Steinernema sp. GSNUS-10, Steinernama sp. GSNUS-14, Heterorhabditis bacteriophora Hamyang, Heterorhabditis sp. GSNUH-1) were evaluated and tried in petri dish, pot, and vegetable greenhouses for environmentally friendly control of beet armyworm, Spodoptera exigua. $LC_{50}$ values of five EPN strains against beet armyworm was different depending on nematode strain and beet armyworm instar. $LC_{50}$ value of Steinernema carpocapse GSN1(GSN1) was 3.8-5.1 infective juveniles(Ijs) in 2nd to 4th instars of beet armyworm. Pathogenicity of five EPN strains against beet armyworm different in nematode strain, concentration, application times, and vegetable species in pot and greenhouse. Steinernema spp. was more effective than Heterorhabditis spp. against beet armyworm. Two or three times of applications of EPN were found to be effective regardless of nematode strain and concentration in pot and greenhouse. ENP showed different reactions on vegetable species. Efficacy of EPN was higher on Chinese cabbage than that on cabbage and kale. GSN1 was one of the most effective nematodes and 100,000 infective juveniles per $m^2$(720,000 Ijs/$7.2m^2=1{\times}10^9$Ijs/ha) resulted in higher mortality in greenhouse.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.1
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• pp.25-30
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• 1993

It is common that in the vegetable cultivation areas, the farmers tend to continue the heavy fertilization to maximize the crop yields in short term. This results in the accumulation of fertilizer elements in the soil and increase in the electrical conductivity of soil. Disregarding these, farmers continue to apply heavy doses of fertilizers. A field experiment was conducted to find out on such a soil whether fertilizer application taking the quantity of nutrients accumulated in the soil into account would save the fertilizer without losing the yield of crop, using Chinese cabbage and spinach as test crops. The findings of the experiment is summarized as following. 1. The yield of Chinese cabbage was not affected by reduction of $19kg\;P_2O_5/10a$ and $7kg\;K_2O/10a$ as compared to farmers doses, and in case of spinach the yield rather was increased under the reduction of $22kg\;P_2O_5/10a$ and $22kg\;K_2O/10a$. 2. The reduction of fertilizers according to plant nutrient status of soils did not affect the inorganic nutrient contents of the crops significantly, in both Chinese cabbage and spinach. 3. A trend was observed that the reduction in the P and K fertilizers application would shorten the storage period of Chinese cabbage. 4. The reduction in P and K fertilizers application resulted in the reduction in available P, exchangeable K, EC and $NO_3-N$ in the soil after the harvest of the crops.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.357-360
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• 1997

To fine out the concentration of $SO_2$ gas in plastic film house, the survey was conducted at 343 sites throughout the nation. The $SO_2$ concentration in plastic film house were similar both heating and non-heating, but $SO_2$ cocentration higher than 0.8ppm was detected at those with heating. The $SO_2$ concentration in plastic film house cultivated red-pepper higher than those of cucumber or tomato cultivation, and it was produced higher amounts at day time than night due to the higher temperature. In plastic film house with heating, $SO_2$ was leaked at brocken parts of heater and joint of stove pipe, sometimes, $SO_2$ discharged from smokestack was resucked with air. $SO_2$ concentration in the plastic film house with and without ventilation were 0.2 and 0.6ppm, respectively.

• Korean Journal of Organic Agriculture
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• v.5 no.1
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• pp.149-165
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• 1996

In order to get some basic datas on environmental friendly funtion against soil and water pollution and safe vegetable production by organic farming, chemical characteristics of soils cultivated by the conventional farming, greengouse cultivation and organic farming and acumulation of NO3--N in chinese cabbage and lettuce were analysed. The highest value of NO3--N in 0-30cm subsoil of organic farming was found among the 3 different farming systems, and it was 3.6 and 6.6 times higher than those of conventional farming in chinese cabbage and lettuce respectively. P2O5 also show high accumulation in the rhizosphere of organic farming compared to convnetional farming. The accumulation of NO3--N and P2O5 in the rhizosphere of organic farming were simial to those of greenhouse cultivation. The NO3- accumulation in chinese cabbage and lettuce by organic farming reach 3224ppm in chinese cabbage and 2543ppm in lettuce and it were 4.7 and 6.4 times higher than those of convnetional farming. It is urgently necessary to introduce the basic standard of IFOAM, EU and FAO/WHO Codex on organic agriculture into korean organic agriculture for operation of environmental friendly system and production of safe vegetable in terms of NO3-.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.147-155
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• 2021

To investigate the incidence of plant-parasitic nematodes (PPNs) in perilla fields in Korea, 55 soil samples were collected from open fields and plastic-film house fields and were analyzed during January 2020 to October 2020. Root-lesion nematodes (RLNs), spiral nematodes, root-knot nematodes, and stunt nematodes were detected in perilla fields, and the incidences of RLNs (39%) and spiral nematodes (55%) were higher than those of other nematodes. Among PPNs, RLNs are very important species found on economic crops. The detection frequency of RLNs was increased due to continuous crop cultivation, and the frequency of fields that cultivated only one crop continuously for over 11 years was twice higher than the frequency of fields that cultivated only one crop for less than 5 years. The PPN species diversity and density were different between leaf-perilla cultivation fields and seed-perilla cultivation fields. In phylogenetic analysis of RLNs, Pratylenchus penetrans, P. vulnus, and Pratylenchoides leiocauda were identified in perilla fields. These results suggest the RLNs should be considered for establishing nematode management strategies in perilla fields in Korea.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.225-231
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• 2009

'Nokkwang' green pepper plants were grown in soil system (silty loam with pH 6.5) under the greenhouse, to determine the effects of subsurface drip irrigation (SDI) and subsurface drip irrigation plus aeration (SDIA) into root zone comparing with conventional surface drip irrigation (DI) in terms of water use efficiency, soil properties, and growth and fruit yield. Two drip lines per crop row were layed on the soil surface in DI system, buried at a depth of 20cm below the soil surface in SDI system, and also buried at a depth of20cm below the soil surface and aerated for 3minutes a hour during the daytime ($08:00{\sim}19:00$) by a air compressor in SDIA system. A automatic irrigation with starting point of -20kPa and ending point of -10kPa based on soil moisture contents was applied by controllers and electronic vacum soil moisture sensors. Reduction in soil moisture contents was delayed in SDI and SDIA, compared to DI. Irrigation amount applied in pepper cultivation was around 30% less in SDI than in DI. Electric conductivity and nitrate nitrogen content in the surface soil grown green pepper were significantly lowered in SSDI and SDIA, compared to DI. Better development of root system was observed in SDIA and SDI than in DI. Results showed that pepper fruit yield increased by 30% in SDIA and 22% in SDI in comparision with DI.

• Korean Journal of Environmental Agriculture
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• v.23 no.3
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• pp.133-137
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• 2004

Recently, saw dust manure has been widely used in horticultural crop production in Korea. Animal manure is produced by decaying of livestock manure mixed with saw dust, and contained higher nutrients and ion concentration than the traditional manure made from rice straw and grasses. Therefore, a continuous application of the animal manure disregarding to soil characteristics may be ruined the soil conditions. This study was conducted to investigate the transportation of the nitrogen, phosphate, potassium, and ion concentration of the animal manure applied to volcanic and non-volcanic soils in Jeju islana Soil chemical analysis were done before and 180 days after animal manure application. After animal manure application, $NO_3$-N moved up to 90cm in volcanic soil, while the movement was limited to 60 cm in non-volcanic soil. Phosphate concentration was high up to 30 cm, where crop roots are mainly distributed, in volcanic soil, however, the phosphate moved up to 60 cm in volcanic soil. Exchangeable potassium moved up to 90 cm in volcanic soil, but the movement wns limited up to 60 cm in non-volcanic soil. For both soil types, no significant different in ion concentrations was observed up to 60 cm in soil depth, though the concentrations were higher in volcanic ash soils as compared to the non-volcanic ash soils.