• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.65-70
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• 1990

Effects of nematode-parasitic fungus, Paecilomyces lilacinus, on root-knot nematode, Meloidogyne hapla, and growth and yield of consecutively grown lettuce and pepper were evaluated and compared to three soil fumigants, Telone II, TeloneC-17 and Dowfune MC-II, in greenhouse plots from 1983 to 1984 at Milyang, Korea. The number of nematodes in fungus plots, Telone II plots, Telone C-17 plots, and Dowfume MC-II plots at 25 days after treatment were 22, 2, 24 and 0, respectively, while untreated control plots were 685. At 350 days after treatment, 66%, 98%, 98% and 96% control of root-knot nematodes were observed in fungus plots, Telone II plots, Telone C-17 plots, and Dowfume MC-II plots, respectively. Lettuce yields were increased 49%, 43%, 31% and 109% and pepper yields were increased 33%, 49%, 37%, and 95% in fungus plots, Telone II plots, Telone C-17 plots, and Dowfume MC-II plots, respectively. Fresh weight and plant height of pepper were higher only in fumigant treated plots than untreated control plots.

• Current Research on Agriculture and Life Sciences
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• v.8
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• pp.29-34
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• 1990

This study was conducted to examine the influence of heat treatment on the $NH_4{^+}$ adsorption by zeolite and to determine the $NH_4{^+}$ loss from $NH_4-$ zeolite during the incubation. The dominant clay minerals of zeolite were clinoptiloiite and mordenite. $NH_4{^+}$ adsorption by zeolite was equilibrated at a 4hrs-shaking. The content of exchangeable $K^+$ of zeolite was increased with increase in the temperature of heat treatment but the amount of $NH_4{^+}$ adsorbed by zeolite was decreased. The amount of $NH_4{^+}$ in the soil treated with ammonium sulfate was decreased during incubation under the submerged condition but the amount of $NH_4{^+}$ adsorbed by zeolite was not decreased in the same course of incubation. It was estimated that $NH_4{^+}$ adsorbed by zeolite was resistant to $NH_4{^+}$-N loss by various reactions.

• Microbiology and Biotechnology Letters
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• v.17 no.2
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• pp.142-147
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• 1989

Six plasmids of B. thuringiensis serovar. kurstaki HD73 were detected, with approximate sizes of 7.4, 7.8, 8.1, 11.3, and 75 Kb, as well as a low copied plasmid of similar length to 75 Kb. Partially cured mutants from B. thuringiensis HD73 were obtained either by the treatment of the curing agent, ethidium bromide(0.02 $\mu\textrm{g}$/$m\ell$) or by spontaneous curing, Acrystalliferous mutants(Cry$^-$) were identified by microscopic observation and immunoblotting with polyclonal antibody against 133 KD deltaendotoxin of HD73. Ten Cry$^-$ mutants were found to be lack of 75 Kb plasmid. These results implicated that this plasmid was associated with delta-endotoxin production, After isolating the mutants, we streaked them on potato dextrose agar, spizizen casamino acid glucose, starch agar, and nutrient agar. Only on starch agar medium did morphologies of Cry$^-$ appear translucent and light greyish. On the other hand, the mutants of B. thuringiensis isolated from Korean soil, designated KBS722, were obtained by the treatment of novobiocin (3 $\mu\textrm{g}$/$m\ell$). Acrystalliferous mutants of KBS722 were less translucent than HD73 mutants' only on nutrient agar medium. Compared the plasmid profile of the mutants with delta-endotoxin production, the results seemed to indicate that the insecticidal protein gene of B. thuringiensis isolates KBS722 located on about 225 Kb plasmid DNA.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.580-586
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• 1989

Penicillium sp. CB-20 was selected for strong polygalacturonase activity among various strains of molds found in soil. The optimum pH for the enzyme activity was 5.0 and optimum temperature was 4$0^{\circ}C$. The enzyme was relatively stable in acidic condition and unstable by heat treatment. The activation energy, Km and V$_{max}$ for the polygalacturonase were 2.499 Kcal/mol, 2.13$\times$10$^{-2}$mol/l, and 104.17 $\mu$mol/min. The activity of polygalacturonase was inhibited by Ag$^{+}$, Cu$^{++}$, Pb$^{++}$, Fe$^{+++}$, $Ca^{++}$, Na$^+$, Mn$^{++}$. The enzyme can be inactivated by the treatment ethylenediamintetra acetic acid, 2,4-dinitrophenol and $H_2O$$_2$. The results indicate the possible involvement of histidine, chelate and terminal amino group as active site. The enzyme was endo-type polygalacturonase.

• Journal of the Korean Wood Science and Technology
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• v.48 no.3
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• pp.376-392
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• 2020

In Korea, damages to wooden cultural properties by termites have been reported all over the country, including Ulleungdo Island and Jeju Island. In order to reduce the damage caused by termites, most cultural properties damaged by them are treated with fumigation or drug treatment on the soil to kill or repel them. The number of treatments is decreasing due to cost and safety problems, and new methods needed to cope with this situation. After extracting an enzyme by selecting only worker termites from the termites collected in Shinan, Jeonnam, as a result of measuring the enzyme activity using xylan of cellulose and hemicellulose that are the components of wood, the activity of termite intestinal enzymes in xylan was higher than that of cellulose having a high molecular weight. Therefore, in this study, as a result of exploring over 600 species of medicinal plant extracts that inhibit the activity of termite intestinal enzymes using xylan as a substrate, the inhibitory effect was significant in Borneolum Syntheticum, Ephedra sinica, and Menthol. Selected Borneolum Syntheticum, Ephedra sinica, and Menthol's extracts not only inhibited the activity of termite intestinal enzymes, but also confirmed that they have insecticidal activation and inhibitory effects on feeding in the result of the direct treatment.

• Korean Journal of Plant Resources
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• v.24 no.5
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• pp.483-488
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• 2011

Cacalia firma recently has been used increasingly as leaf vegetables but endangered in natural forest. In this work, we established the plant regeneration via adventitious shoot formation from petiole segments of seedling and in vitro plantlets. Wounding of seed coats and $GA_3$ treatments were effective to induce in vitro germination of seeds, whereas, seed did not germinate at all without these treatment. When cotyledon, leaf, petiole, and root segments of seedling were cultured on medium with 2 $mg{\cdot}L^{-1}$ benzyl adenine (BA) and 0.5 $mg{\cdot}L^{-1}$ naphthaleneacetic acid (NAA), petiole segments showed highest number of shoots per explant among the other segments. Among the various kinds of cytokinins, BA, isopentyl adenine (2-ip), kinetin, zeatin, thidiazuron (TDZ), TDZ and BA treatments were effective to induce high frequency of adventitious shoot formation from petiole segments of in vitro propagated plants. NAA stimulated the frequency of adventitious shoot formation but not for number of adventitious shoots per explants compared to TDZ or BA treatment alone. Most of adventitious shoots were developed directly from surfaces of explants. Adventitious shoots were transferred on medium with IBA for root formation, thereafter the plantlets were successfully transferred to soil.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.75-83
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• 2013

The present study was examined seed germination and growth characteristics of Cynanchum wilfordii under the following conditions such as soaking temperature, concentrations of $GA_3$, trays and soil types, and shading conditions. In seed pre-treatment, germination rate was the highest at 93% when soaked in 100 ppm $GA_3$ at $20^{\circ}C$ and seedling growth was best in 50 plug cell tray. Physiological quality was best in the condition in which seeds were treated with 10 ppm $GA_3$ at $20^{\circ}C$. Taking into consideration the seedling growth, their physiological quality as well as economical aspects, seedlings with plant height (over 10 cm) and root length (over 10 cm) were grown vigorously 30-45 days after the seeds were sown in mid-April in TKS, TKS+perlite and TKS+rice hull of 128 or 200 plug cell tray.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.352-357
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• 2007

We investigated effects of concentration and duration were investigated in order to promote efficiency of $CO_2$ enrichment in winter. The treatments were conducted with two levels of $CO_2$ concentration, namely 400 ppm, 700 ppm, two levels of duration, 3 h (9:00-12:00), 6 h (9:00-15:00), and control (nonenrichment $CO_2$). Fresh weight of leaves increased under longer exposure to $CO_2$ and higher $CO_2$ concentration. Fresh weight of stem and root increased under longer exposure to $CO_2$, but decreased under higher $CO_2$ concentration. Total dry weight increased under longer exposure to $CO_2$ and higher $CO_2$ concentration. Combination treatment of longer exposure to $CO_2$ and higher $CO_2$ concentration showed the largest decrease of Root : Shoot dry weight ratio. The $700ppm{\times}6h$ treatment showed higher fruit number and yield than control. The results suggested that the growth under longer exposure to 400 ppm $CO_2$ was better than that under higher $CO_2$ concentration.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.379-387
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• 2007

This research was conducted to evaluate the influence of pre-planting fertilizer levels (PFL) and initiation time of fertigation (ITF) on growth and nutrient contents of tomato plug seedlings. The pre-planting fertilizer levels in a coir+peatmoss+perlite (4:4:2, v/v/v) substrate were adjusted to 0.5X, 1.0X and 1.0X, and initiation time of fertigation was set to 7, 14,21 and 28 days after sowing. Elevated PFL in same ITF increased plant growth such as fresh and dry weights at 35 and 70 days after sowing. Plugs with early feeding among treatments of equal amount of PFL also showed better growth as compared to those of later feeding. In each ITF, 0.5X treatment had the higher tissue $P_2O_5$ contents than 1.0X and 1.5X treatments. Elevated PFL resulted in the decrease of tissue K, Mg and Fe contents and increase of tissue Ca contents. The pH in soil solution of all root substrates except 0.5X treatment at 35 and 70 days after sowing were greater than 7.0, which is too high. This suggests that the amounts and kinds of Ca containing fertilizers should be altered to decrease the pH. The results of this research indicated that fertilizer levels should be increased to 1.5X except Ca fertilizer, and fertigation immediately after moving plug trays from germination room to greenhouse is required to increase crop growth and decrease cropping time.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.4
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• pp.93-99
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• 2000

Treatment of shaving scrap, a chrome containing solid scrap generated by leather manufacturing process, has been so far depended on mainly incineration, soil landfill and ocean dumping, which give bad impact on environment and cause pollution. Shaving scrap generates from the mechanical work for controlling the final thickness of leather and its main components are collagen protein and pan of chromium compound. For the purpose of reusing this leather waste as resources, researches in connection with collagen fiber recovery, gelable protein recovery and liquid fertilizer is being speedily progressed. In the experiment, shaving scrap went through wet pulverizing treatment by physical and chemical methods. Then, making the leather sheet evenly, it is mixed with natural latex and every kind of binding materials in the container, and the mixtures were passed through experimental hydraulic press machine and applied to Fourdrinier machine respectively. Lastly, a test for fading out physical strength and properties of multiple-purpose of leather-like material was performed on a continuous leather sheet prepared by the experiment. In result, the physical strength and properties of leather-like material showed noticeable differences according to mixing ratio of binding materials, beating methods and the Ends of binding materials selected, and generally tear strength was the weakest property among others. Also, by the pilot scale experiment in sequence, it was possible to manufacture recycled goods made of soft and hard types of leather-like material with various performances.