• Korean Journal of Weed Science
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• v.15 no.2
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• pp.131-140
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• 1995

This experiment was conducted to test the effect on germination and seedling growth of major industrial crops and weed control potential using alfalfa plant. When dried alfalfa residues were mixed into vermiculite, germination, length of shoot and root of crops, such as Perilla frutescens, Sorghum nevosum, Platycodon grandiflorum and weeds, Digitaria saguinalis, Setaria viridis, Siegesbechia pubescens, Ammaranthus lividus, and Solanum nigrum, were significantly inhibited as the dried residue concentration increased. More than 10% concentration of the dired residue caused 80% germination and growth inhibition. The fresh alfalfa exudation also inhibited the germination and seedling growth of crop, barley, rye, alfalfa, and sesame, and weeds, Echinochloa crus-galli, Siegesbechia viridis, and Portulaca oleracea. The degree of inhibition showed the different response according to the fresh exudation concentration, types of crops and weeds. Generally, as the exudation concentration increased, the germination and seedling growth of crops and weeds inhibited. The exudation of dried residue also exhibited the strong inhibition effect on germination and seedling growth of crops, alfalfa, Platycodon grandiflorum, barley, sesame, rye and weeds, D. sanguinalis, S. pubescens, S. viridis, P. oleracea, E. crus-galli, At the 10% concentrations, S. pubescens, and P. oleracea were not germinated and showed only 15% germination in the S. viridis. From this study, would conclude that alfalfa plant contained water soluble phytotoxic substances which were inhibitory to weeds and crops. This results suggest that alfalfa had some possibility to control some weed species using toxic compounds like natural herbicide.

• Journal of Bio-Environment Control
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• v.14 no.4
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• pp.239-244
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• 2005

This study was carried out to investigate the growth characteristics and root development of Mandshurian Linden (Tilia mandshurica Rupr. et Max.) seedlings grown in plastic net container and plain plastic container. The seedlings were grown in the mixture of peatmoss perlite : vermiculite (1:1:1, v/v/v) for five months in the plastic greenhouse. The seedlings grown in plastic net container showed greater root collar diameter growth, better root development, and more increment of root dry mass than those grown in the plain plastic container. In particular, the seedlings grown in plastic net container had no spiraling roots which were always observed in the control . These results suggest that the net container is suitable for container culture of Tilia mandshurica seedlings by enhancing root development. Seedlings grown in the net container and transplanted to various environments showed vigorous rootage and growth.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.16-25
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• 1992

A pot experiment was conducted to understand effect of soil temperaute on soybean shoot and root growth, and its relations to nutrient uptake including phosporus and potassium. Pregerminated soybean seedlings, Paldal cultivar, were planted for 43 days on the pots with Ihyeon silt loam and Samgag sandy loam in the temperature controled water baths at 17, 25 and $32^{\circ}C$. Shoot and root samples were taken at four times and analyzed. Shoot and root dry matter weights were heavier as higher soil temperaure. The root dry matter increased faster than shoot at earlier period. Shoot dry matter weights grown at 17 and $25^{\circ}C$ showed little difference between two soils, however, those grown in silt loam at $32^{\circ}C$ were heavier than sandy loam. The total lengths of roots were longer as higher soil temperature, and longer in silt loam than sandy loam. The roots grown in sandy loam at low temperature were thicker than the roots grown in silt loam at high temperature. The uptakes of phosphorus and potassium were higher as higher tempeature with same trend with dry matter. The uptake rate of unit root surface area was higher in sandy loam soil than silt loam. The uptake rates showed strong dependence on soil temperature as well as dependence of water uptake rate. Based on Dalton and Gardner model, at high temperature the dependence trend of phosphorus and potassium on soil temperature showed with active uptake model, while at low temperature the dependence showed without active uptake model.

• Applied Biological Chemistry
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• v.39 no.1
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• pp.20-24
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• 1996

Pseudomonas fluorescens ps88 was isolated from the rhizosphere soil produced the secondary metabolite called siderophore under iron Limited conditions. On iron limiting KMB medium this strain inhibited the growth of Pythium ultimum, Pyricularia oryzae, Rhizoctonia solani and Xanthomonas oryzae. Cucumber seeds were coated with the strain ps88 and were grown in green house soil. Forty days after the seed emergence, disease incidence caused by Fusarium oxysporium was reduced up to 50%. When the cucumber plants were grown in vermiculite, a significant fresh weight was increased. Root development of red pepper plants was also enhanced on MS medium supplemented with siderophore.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.10-16
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• 1980

Five of each lowland and upland rice varieties were planted in a seedling hox with three replications of randomized complete block design and it was desiccated up to complete water stress in certain leaf stage. The desiccated rice plants were supplied with water again to check survival ability of rice plant from wilting. All of the lowland varieties which showed lower yield in upland condition were superior to upland varieties in recovery ability from desiccation. Some of the morphological characteristics in relation to the recovery ability also were discussed.

• Journal of Life Science
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• v.13 no.5
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• pp.582-589
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• 2003

The effect of useful rhizobacterium added in bed soil on the early growth promotion of red pepper plug seedlings was investigated. Total 540 colonies of rhizobacteria from 385 samples of eggplant family roots were isolated. Among these, 5 isolates were selected for antifungal activity against pathogenic fungi such as Alternaria solani, Botrytis cinerea, Fusarium oxysporium, Phytophthora capsici, and Sclerotia sclerotiorum. Of all the isolates, MJ-3 having the most pronounced growth-promoting ability for red pepper was finally selected and identified as Bacillus amyloliquefaciens through characterization of biochemical and bacteriological aspects and 16S rDNA sequence. The plant height, stem diameter, root length and fresh weight of red pepper plants which were grown with inoculation of B. amyloliquefaciens MJ-3 were higher than those without inoculation. Especially the root weight of the inoculated red pepper plant increased by 44.3%, the content of endogenous plant hormone (CA$_1$) being 0.556 ng/g (dry weight).

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.47-55
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• 2016

The purpose of this study was to control root-knot nematode, Meloidogyne incognita on pumpkin seedling with 10%, 20% coffee ground compost and 1% plant velvet bean powder (plain skin bean, leopard skin bean, hole plant, bean pod). Among the root-knot nematode insecticide treatments, the velvet bean plant powder was the highest mortality rate with 83.2% in greenhouse condition. In addition, the root-knot nematode second juvenile mortality significantly increased with the lapse of processing time for each concentration of leopard skin velvet bean extract in vivo. After 24 hours, the mortality rate of root-knot nematode showed the highest at 1.2% and 2.4% of leopard skin velvet bean extract. The growth promoting effect of seedlings pumpkin, 20% of coffee ground compost treatments inhibited the growth of pumpkin seedlings and 1% the tiger pattern velvet beans powder was the most to promote the growth of pumpkin seedlings. However, the results indicated that the organic materials of velvet beans and coffee ground compost are expected to be able to effectively control the root-knot nematode and further studies will be needed for the concentration and application methods.

• Research in Plant Disease
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• v.17 no.2
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• pp.155-160
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• 2011

To develop the efficient screening methods for antifungal compound active to Chinese cabbage clubroot caused by Plasmodiophora brassicae, the control efficacy of three fungicides fluazinam, ethaboxam, and cyazofamid on the disease was tested under several conditions such as soil types, cultivars of Chinese cabbage, growth stages of the host, and inoculum concentrations. The in vivo antifungal activities of the fungicides on clubroot of two Chinese cabbage cultivars were hardly different. At 7- and 14-day-old seedlings, the fungicides were more effective to control of clubroot than at 21-day-old seedlings. In a commercial horticulture media soil (CNS), disease severity of untreated controls was higher and control activity of the fungicides was less than in a mixture of CNS and upland soil (1:1, v/v). Disease development of the seedlings inoculated with P. brassicae at $1.8{\times}10^7$ spores/pot to $1.1{\times}10^9$ spores/pot was almost same, but control efficacy of the fungicides was negatively correlated with inoculum dosages. To effectively select in vivo antifungal compound on Chinese cabbage clubroot, 14-day-old seedlings need to be inoculated with P. brassicae by drenching the spore suspension to give $1{\times}10^8$ spores/pot 1 day after chemical treatment. To develop clubroot, the inoculated plants are incubated in a growth chamber at $20^{\circ}C$ for 2 days, and then cultivated in a greenhouse ($20{\pm}5^{\circ}$) for four weeks.

• Research in Plant Disease
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• v.20 no.2
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• pp.112-118
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• 2014

A liquid bio-formulation containing chitinolytic bacteria, chitin and their products was assessed for its potential biological control against root-knot nematodes on cucumber. The bio-formulation was prepared by cultures of three chitinolytic bacteria, Chromobacterium sp. strain C-61, Lysobacter engymogenes and Serratia plymuthica in minimal medium supplemented with chitin. Under pot conditions, the bio-formulation showed better growth of cucumber plants, and less root galls and population density of Meloidogyne spp. than control media without the bio-formulation. In a greenhouse, 75-fold diluted bio-formulations were treated instead of water around cucumber plants through hoses for drip irrigation six times at 5-day intervals from the transplanting date. After 30 and 60 days, the treatment provided about 7% and 10% enhancement in the plant height and about 78% and 69% reduction in population density of Meloidogyne spp. in the rhizosphere, respectively. In addition, the experiments showed that the control effects occurred only in the soils contacted with the bio-formulation. Undiluted bio-formulations were drenched three times at 10-day intervals around cucumber plants severely infested with Meloidogyne spp. The treatment showed about 37% plant enhancement without dead plants compared with 37% death in the untreated control, and about 82% nematode reduction. These results suggest that the bio-formulation can be practically used to control the root-knot nematode on cucumber.

• Korean journal of applied entomology
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• v.32 no.4
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• pp.382-388
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• 1993

Five nematophagous fungi, Arthrobotrys arthrobotryoides, A. conoides, A. oligospora, Dactylella lobata and Fusarium oxysporum were evaluated for nematicidal effect on Meloidogyne hapla in greenhouse. Treatment of nematophagous fungi reduced the root galling by M. hapla and increased red-pepper growth in naturally infested pot soil. Number of galling were significantly less inall pots in 4 different inoculum densities of 5 nematophagous fungi compared to untreated plots. Especially, treatment of F. oxysprum resutled significant reduction of root gall of red-pepper. The increased shoot growth was significantly higher in pretreated plots by A. arthrobotryoides, A. conoides, A. oligospora, D. lobata and F. oxysporum at inoculum concentration of 1:100 but other treatments were not significantly increased shoot growth. Two promising fungi, D. lobata and F. oxysporum were selected in greenhouse test and in vitro results of previously experiment and applied to field plot naturally infested by M. hapla serverely. Number of galls were remarkably fewer in plots treated with D. lobata and F. oxysporum at either 1:70 or 1:100 concentration compared to the untreated plots. The shoot growth of red-pepper was increased strikingly in the plots following the red-pepper was increased strikingly in the plots following the treatment of both fungus than greenhouse test.