• Korean Journal of Organic Agriculture
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• v.32 no.1
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• pp.75-90
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• 2024

Biochar is a solid substance with a high carbon content, as it is made out of biomass pyrolyzed under the condition of limited oxygen. This product has attracted attention as an environment-friendly soil amendment because it contributes to carbon neutrally and has improvement effects on the soil environment. This study conducted an experiment to evaluate soil physiochemical properties and microbial community changes in a melon greenhouse according to the applied amount of biochar to investigate the growth characteristics and yields of melons accordingly. In soil physical properties, an increase in the applied amount of biochar resulted in a decrease in bulk density and an increase in porosity of the soil, improving air permeability. In soil chemical properties, an increase in the applied amount of biochar led to a increasing of pH, organic matter and available phosphate content. In the growth characteristics of melons, there was a growing tendency of plant height, leaf length and leaf width according to the increasing application of biochar until 10,000 kg/ha. Moreover, melon yields also increased as the amount of biochar, 13~16% higher in 10,000 kg/ha biochar application than no treatment. Compared differences among microbial communities in the soil according to the application of biochar and found that plant beneficial bacteria dominated in biochar treatments. This study demonstrated the potential of biochar as an effective soil amendment in melon greenhouse by showing improvements in soil physicochemical properties and microbial communities.

• Korean Journal of Environmental Agriculture
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• v.20 no.1
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• pp.8-14
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• 2001

To investigate the effects of waste sludge from antibiotic fermentation on the growth of young radish and chemical properties of soil, five levels of fertilizer, control (recommended fertilizer, $N-P_2O_5-K_2O=160-59-104$ kg/ha), AS(control + sludge 1,000 kg/ha), AC(control + conventional compost 1,000 kg/ha), SNS(control - subtracting 30% N of sludge + sludge 1,000 kg/ha) and SNC(control - subtracting 30% N of conventional compost + conventional compost 1,000 kg/ha) were applied and radish was grown twice with same treatments on May and August in 1998. Germination rate and early growth of young radish grown with AS and SNS were lower than those grown in control and with AC, SNC. This negative effects by adding the sludge in the early growth seemed to be caused by damage of ammonia gas released during degradation of the sludge in soil. However, yield of young radish showed no significant difference among all the treatments including the AS and SNS at the 1st and 2nd experiment, and these suggested that the latter half of growth of young radish was accelerated by adding the sludge. Contents of T-N in young radish and inorganic N in soil showed a tendency to increase by adding the sludge while antibiotic substance, cephalosporin-C, was not detected in plant material and soils after harvest of young radish in both experiments. Consequently, waste sludge from antibiotic fermentation, which contains high levels of organic matter and nitrogen could be used as an useful resource in agriculture.

• The Korean Journal of Mycology
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• v.39 no.2
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• pp.91-98
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• 2011

Oudemansiella mucida, an edible and medicinal mushrooms belonging to Tricholomataceae of Basidiomycota, has been known to produce antifungal substances to inhibit the mycelial growth and spore germination of the plant pathogenic fungi. To produce good amount of antifungal substances from culture media, the optimal culture conditions of O. mucida were investigated. The most favorable conditions for the mycelial growth were $25^{\circ}C$ and pH 5 in potato dextrose agar. The most favorable carbon and nitrogen sources promoting mycelial growth were maltose and calcium nitrate, respectively. The optimum C/N ratio was about 20 : 1 in case that 3% glucose was supplemented to the basal medium as a carbon source. The optimal mycelial growth of O. mucida was found in the Hennerberg medium. The crude extract from submerged culture of potato dextrose broth exhibited inhibition of mycelial growth of Colletotrichum acutatum, Botrytis cinerea and Pyricularia oryzae but, fungicidal activity is not good enough to compared with commercially available fungicides tested. Therefore, the antifungal substances extracted from submerged culture of O. mucida might have a potential to be used for biocontrol agent of fungal diseases of plants.

• Weed & Turfgrass Science
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• v.3 no.1
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• pp.41-49
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• 2014

Four preparations of liquid turfgrass fertilizers were tested cool season turfgrasses during fall season. The preparations of PS-A, PS-B, PH-C and PH-D for commercial products were contained with essential nutrient elements, seaweed extract, amino acids, and humus substance. Growth and quality of creeping bentgrass (Agrostis palustris Huds cv. Penn-A1) and Kentucky bluegrass (Poa pratensis L.) mixture (Midnight 33%, Moonlight 33%, Prosperity 33%) were evaluated by normalized difference vegetation index (NDVI), root length and fresh weight, shoot density, turf color, and chlorophyll content. Three foliar sprays of 4 preparations with an interval of 7 days were made in the fall of 2013 in the sod production field at Hapchun, Korea. No significant difference among 3 preparations was found in NDVI of creeping bentgrass. However, PS-A was significantly increased NDVI of Kentucky bluegrass. Two to three applications of PS-A significantly increased chlorophyll content and turf color. Three foliar sprays of PS-A and PS-B were significantly increased the shoot density of Kentucky bluegrass on 20 days after final application. These results may indicate that the use of some preparation is beneficial in producing higher quality turfgrass sod with better color and chlorophyll content during fall season.

• The Journal of Natural Sciences
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• v.1
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• pp.115-198
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• 1987

The present studies were undertaken to elucidate the influence of auxins, auxin-like substance-ethychlozate ("Figaron"),and pH and sort of rooting media on rooted propagation of certainornamental woody plant cuttings, and to see possible changes in internal compositions characterizing after root-promoting treatment as the cutting stage proceeded. The experimental check-up srevealed and summarized as seen in the following;I. Effect of three different auxin treatments on rooting cuttings: 1) Promotive influence of auxin varied according to different concentration levels, hours of dipping treatment of the auxins, and kind of plants. The greatest effect was obtained for Forsythia ksreana with NAA and IBA, for Ligustrurn obtusifolium var. variegatum with NAA and ethychlozate, for Hydrangea macrophylla, Magnolia kobus, and Magnolia liliflora with NAA, lBA and ethychlozate also. The most effective level of the promotive agents was found 200mg/l for NAA, 1000mg/l for IBA, and 200mg/l for ethychlozate. For Weigela florida and Gardenia jasminoides, range of the most effective level was shown relatively wide spread. 2) NAA was more effective at its optimal level of the rooting agent than ethychiozate for Weigela florida, Viburnum awabuki, Forsythia koreana, Acer palmatum 'Nomura', Bouga invillea glabra, Elaeagnus umbellata, Prunus tomentosa, Ligustrum obtusifolium, Pyracantha coccinea, Cestrum noctu rnum, Hydrangea macrophylla, Codiaeum variegatum, Rhododen dron lateritium, and Ilex crenata var. macrophylla, and yet ethychlozate was found either as equally as effective or more so than NAA for Zebrina pendula, Hibiscus syriacus, Fatshedera lizei, Schefflera arboricola, Campsis grandiflo ra, Ixora chinensis, Euonymus japonica, and Magnolia liliflora. On the contrary, no the auxin effect was noted with Lagerstroemia indica, Trachelospermum asiaticum, and Syringa vulgaris. This probably indicates that these species are genetically different for the auxin response.II. Effect of different pH and sorts of cutting media on rooting cuttings: 1) Bougainvillea showed best in rooting for the number and dry weight at pH 6.5, more with ethychlozate than NAA, while Ligustrum did at pH 5.0 more with NAA than ethychlozate. pH 4.0 medium resulted in the best rooting for Rhododendron with NAA, more than ethychlozate. 2) Use of cutting medium with peat: perlite: vermiculite = 1:1:1 showed to give the greatest rooting percent and dry weight, apart from considering the number of roots. This apparently meant the fact that cutting medium has more to do with root growth than root differentiation. Rhododendron yet showed results with cutting media that use of peat: perlite = 2:1 mixed is more effective on rooting than using peat alone.III. Effect of auxinic treatments on rooting cuttings and change in some cutting compositions: 1) Under the climatic conditions of July having temperature $26.3\pm$$2.4^{\circ}C$for cutting bed, new roots of Magnolia started to show up generally 20 days after the cutting was made, whereas Cestrum did much earlier than that, namely 14 days after. 2) Although total carbohydrate content of Magnolia cuttings showed no marked change without auxin treatment, it did so with the treatment, especially 30 days after the start of cutting. Cestrum cuttings demonstrated a gradual in crease in total carbohydrate content as rooting took place, and the content became reduced more with auxin than with out, just about when rooting proceeded to 14 days after the start of cutting. 3) Magnolia generally showed an increase in total nitrogen content as rooting proceeded more, and Cestrum showed a decrease in total nitrogen of cuttings. The auxin treatment exhibited no pertinent relation with change in plant nitro gen when rooting is promoted with auxin treatment. 4) An abrupt drop of total sugar and reducing sugar was noticed as Magnolia rooting started, and this reduction was parti cularly outstanding with auxin treatment. Starch content also was decreased in the later stage of cutting with auxin treatment, and was rather increased without auxin. Although sugar content soon increased as cutting started with auxin treatment in the case of Cestrum, it became reduced after rooting took place. 5) Total phenol content increased with rooting, and this was especially true when rooting started. This increase was reversed somehow regardless of auxin treatment. A decrease in phenol of Magnolia was found more striking with auxin than without in the later stage of the cutting period. 6)Avena coleoptile test for auxin-like substances presented the physiologically active factor is more in easy-to-root Magnolia liliflora than hard-to-root Magnolia kobus, and the activity of auxin-like substances was much increased with auxin treatment. The increase in the growth promoting substances was markedly pronounced when rooting just started. The active growth substances decreased in the later stage of cutting, and certain inhibitory substances started appearing. Cestrum also showed physiologically similar growth promoting substances accompanying auxin-like active substances if auxin is treated, and some strong inhibitory substances seemed to appear in the later stage of cutting. 7) Mung-bean-rooting test indicated biologically that endogenous growth substances in Magnolia all promoted mung-bean rooting, and activity of the growth substances apparently stimulated mung-bean rooting with auxin more than without. Here auxin treatment seemed to give a rise to an increased activity of endogenous growth substances in cuttings. This activity was found much greater with either NAA or IBA than ethychlozate, and showed its peak of the activity when rooting first started taking place. Certain inhibitory substances for Avena coleoptile growth strongly promoted mung-bean rooting, and it was also much like in the case of Cestrum.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.205-210
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• 1994

This study was conducted to develop a method of mass production by cutting of superior genotypes of Larix leptolepis and to examine the effects of ortet age, clone, crown position, and an applied plant growth substance upon the rooting of cuttings. Four different ortet ages, 2, 8, 16 and 30 years and three levels of root-promoting substances, indole butyric acid(IBA), at 1000, 2000, and 5000ppm were employed. Greenwood cuttings were taken from mother trees in late July and rooted for three months in rooting medium containing peatmoss : vermiculite : perlite(1 : 1 : 1 by volume). with temperature controlled at $20-25^{\circ}C$, humidity by intermittent misting and light by partial shading in the greenhouse. Cuttings treated with 1000ppm IBA showed highest rooting, with 80%, 71%, 52%, 25% for 2-, 8-, 16-. 30-year-old ortet, respectively. Untreated cuttings showed rooting of 52%, 48%, 36%, 20% for the ortet age of 2, 8, 16, 30 years, respectively. The average number of adventitious roots decreased with increasing ortet age from 2 to 30 years, whereas IBA treatment increased the number of roots in all ages. A variation in rooting among 20 clones tested was observed. The 4 clones, Chungnam 6, and 7 and Chonbuk 1, and 9 showed good rooting of about 67%, while Kangwon 49 showed boor rooting of 40% at 1000ppm IBA treatment. When crown position was compared, cuttings taken from middle crown showed highest rooting of 60%, while cuttings from upper crown showed lowest rooting of 53%.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.96-103
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• 2009

For the control of pathogenic microorganisms, Bacillus spp. were isolated from diseased pepper fruits in Korea. Among them, Bacillus sp. IUB158-03 showed high inhibitory effect on mycelial growth and spore germination of C. gloeosporioides and Botrytis cinerea. The strain was identified as B. amyloliquefaciens IUB158-03 based on its physiological, biochemical characteristics and Microlog analysis. The highest level of antifungal substances by B. amyloliquefaciens IUB158-03 were obtained when the bacterium was cultured in medium containing 2% soluble starch, 3% yeast extract, 0.5% tryptone, 0.5% $NH_4H_2PO_4$, and 1% NaCl (pH 6.0) at $25^{\circ}C$ for 72 hrs. The antifungal substances were purified by butanol extraction, silica gel column chromatography, preparative thin layer chromatography, and high performance liquid chromatography. The purified antifungal substance was confirmed $R_f$ 0.27 by TLC. This substance exhibited antifungal activity against Fusarium solani, Rhizoctonia solani, Botrytis cineria, Alternata alternaria of plant pathogenic fungi and Trichophyton mentagrophytes, Epidermophyton floccosum, Cryptococcus neoformans of human pathogenic fungi.

• Korean Journal of Food Science and Technology
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• v.33 no.4
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• pp.401-408
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• 2001

The ethanol extract and n-hexane fraction of Commiphora molmol Engl. showed minimum inhibitory concentration of 50 ppm and 25 ppm, respectively, on 5 strains of Listeria monocytogenes at $32^{\circ}C$. The purified substance, C3-3-2 fraction, was isolated by silica gel column and preparative thin layer chromatography from n-hexane fraction of Commiphora molmol Engl. The C3-3-2 fraction showed a strong bactericidal activity on 5 strains of L. monocytogenes at the concentration of 10 ppm in tryptic soy broth medium. At that concentration, the viable count was reduced $5{\sim}6$ log cycle from initial cell number. The n-hexane fraction of Commiphora molmol Engl. showed strong growth inhibition at the concentration of 25 ppm on Bacillus cereus and Staphylococcus aureus, at 50 ppm in broth on Salmonella enteritidis, and at 500 ppm on Vibrio parahaemolyticus. The purified antimicrobial substance, the C3-3-2 fraction, was identified as m-nonylphenol by on the basis of the $^1H-,\;^{13}C-NMR$ and EI/MS data. For the application test, the C3-3-2 fraction which was purely isolated from Commiphora molmol Engl. at 100 ppm were applied to minced Alaska pollack and ground beef at $32^{\circ}C$ and $5^{\circ}C$. The antimicrobial substances did not reduce L. monocytogenes ATCC 19113 at $32^{\circ}C$, while they reduced L. monocytogenes ATCC 19113 in viable number at $5^{\circ}C$. However, the antimicrobial effect of C3-3-2 fraction in food system was lower than that of broth condition.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.411-419
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• 2019

The purpose of this study was to analyze the growth and functional differences between C. rotundus and G. littoralis according to different electrical conductivity (EC) conditions in reclaimed soil conditions. C. rotundus and G. littoralis seeds were sown in a tray and managed for seedlings stage for eight weeks. They were transplanted in the pots containing reclaimed soils sampled in the Saemangum region. The plants were grown in the reclaimed land soil for 12 weeks under the control, 1, 2, 4, and $8dS{\cdot}m^{-1}$ conditions and in horticultural soils with EC $1.0dS{\cdot}m^{-1}$. Plant height, leaf length and width of C. rotundus were the highest in EC $1dS{\cdot}m^{-1}$. Leaf, flower and tuber numbers of C. rotundus were the highest in EC $2dS{\cdot}m^{-1}$ and the lowest in EC $8dS{\cdot}m^{-1}$, and SPAD was the highest in EC 2 and $4dS{\cdot}m^{-1}$ and the lowest in EC $8dS{\cdot}m^{-1}$. The fresh weights of shoot and root of C. rotundus grown under EC $2dS{\cdot}m^{-1}$ increased and then decreased as the concentration increased. When compared plant growth between reclaimed soil and horticulture soil with EC $1dS{\cdot}m^{-1}$, the fresh weights of shoot and root, SPAD, leaf number, flower number, and tuber number were higher in horticultural soils. Although G. littoralis grown under EC $8dS{\cdot}m^{-1}$ was the lowest in all growth parameters, there were no significant differences among other EC treatments. C. rotundus had the highest p-coumaric acid content in EC $1dS{\cdot}m^{-1}$. And the catechin content in shoot of G. littoralis was the highest in the control, and root of Glehnia littoralis had the highest benzoic acid contents in EC $1dS{\cdot}m^{-1}$. If the soil EC is well managed within $4.0dS{\cdot}m^{-1}$, two plants would be cultivated in reclaimed land.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.1
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• pp.33-41
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• 1997

This study was carried out to establish simple and easy methods to judge the survival, senescence and death of the protoplasts in culture system by identifying the marker substance related to metabolic status of the cells. When rice and tobacco protoplasts were cultured in MS and KM-8P media containing 2,4-D or coconut milk ABA decreased especially in the media containing coconut milk, but GA$_3$, IAA and zeatin increased as the cultures progressed. The decrease of ABA and increase of zeatin was especially remarkable. When the supraoptimal amount of osmoticum (mannitol) was added to the culture media ABA decreased after a momentary increase, but other growth hormones slowly increased as the concentration of the osmoticum increased. Contents of individual hormones were contrasted when protoplasts rice and tobacco were cultured on the same medium containing 10mM super mine or NaCl. Tobacco protoplasts were more sensitive to NaCl stress and stopped protoplast division at the late stage of culture. Protoplast viability decreased greatly in 48 hours when the protoplast were at 32$^{\circ}C$ on a medium lacking several components. ABA content increased up to 10 days from incubation in negative proportion to the protoplast viability. On the other hand contents of other growth hormones, especially zeatin, decreased. The present results clearly showed that the contents of individual growth hormones in the plant protoplasts in culture varied sensitively in response to environmental factors that they are faced with. This indicates that the physiological states of the protoplast, such as survival, senescence or death can be simply judged based on the quantitative analysis of those hormones by ELISA.