• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.246-253
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• 1994

Four Quercus forests in Mt. Mohu were studied to investigate biomass, net production and effective biomass estimation method. Five $10m{\times}10m$ quadrats were set up, ten sample trees were cut and roots of three sample trees were excavated for dimension analysis in each forest. There was little difference in accuracy among three allometric biomass regression models of logWt=A+BlogD, $logWt=A+BlogD^2H$ and logWt=A+BlogD+ClogH, where Wt, D and H were dry weight, DBH and height, respectively. Analysis of covariance showed that there were no significant differences among slopes and intercepts of allometric biomass regressions, logWt=A+BlogD, of four Quercus species. Biomass of Q. acutissima, Q. nariabilis, Q. serrata and Q. mongolica forests were 164.0, 158.9, 115.3 and 118.9t/ha, respectively. Net production of Q. acutissima, Q. variabilis. Q. serrata and Q. mongolica forests were 25.0, 23.2, 14.5 and 12.6t/ha/yr., respectively. The proportion of roots to total biomass and total net production of Q. mongolica forest was higher than that of three other species forests. Net assimilation ratio of Q. acutissima, Q. variabilis, Q. serrata and Q. mongolica forests were 2.87, 2.80, 3.20 and 2.95, respectively. Relatively less leaf biomass of Q. serrata and Q. mongolica forests were the reason why total biomass and total net production of Q. serrata and Q. mongolica forests were less than those of Q. acutissima and Q. variabilis.

• Journal of Korean Society of Forest Science
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• v.82 no.2
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• pp.188-194
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• 1993

A natural Quercus variabilis forest and a Populus alba${\times}$P. glandulosa plantation in Mt. Mohu area were studied to investigate aboveground biomass and net production. A $20m{\times}30m$ quadrat was set up in each stand, and 10 sample trees each of Quercus variabilis and Populus alba ${\times}$ P. glandulosa were cut for dimension analysis. There was little difference in accuracy among three biomass regression models of logWt=A+BlogD, $logWt=A+BlogD^2H$, and logWt=A+BlogD+ClogH, where Wt. D, and H were dry weight, DBH, and height, respectively. Aboveground total biomass of Quercus variabilis stand was 31,275kg/ha, and that of Populus alba ${\times}$ P. glandulosa was 55,581kg/ha. In both of Quercus variabilis stand and Populus alba ${\times}$ P. glandulosa stand, the proportion of each tree component to abovegound total biomass was high in order of stem wood, branches, stem bark, and leaves. Quercus variabilis stand was higher in the proportion of stem bark, branches and leaves than Populus alba ${\times}$ P. glandulosa stand, while the former was lower in that of stem wood than the latter. Aboveground total net production of Quercus variabilis stand was 4,267kg/ha/yr., and that of Populus alba ${\times}$ P. glandulosa stand was 3,903kg/ha/yr. The proportion of each tree component to aboveground total net production of Quercus variabilis stand was high in order of leaves, stem wood, branches, and stem bark. That of Populus alba ${\times}$ P. glandulosa stand was high in order of stem wood, leaves, branches, and stem bark. Net assimilation rate and efficiency of leaf to produce stem of Quercus variabilis stand were 2.121 and 0.840, respectively. Those of Populus alba ${\times}$ P. glandulosa stand were 3.376 and 2.085, respectively. Though Populus alba${\times}$P. glandulosa stand was lower in aboveground total net production than Quercus variabilis stand, the former was higher in aboveground total biomass than the latter. The reason was that Populus alba${\times}$P. glandulosa stand was higher in net production of stem wood of accumulation organs than Quercus variablis stand.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.56-68
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• 1985

This study was conducted (1) to measure the nitrogen content of various parts of trees in a 24-year-old Pinus koraiensis plantation, providing a harvest method with the least impact on the self-serving mechanisms in the nitrogen status of the ecosystem and (2) to examine the seasonal changes in inorganic nitrogen (ammonium salt and nitrate, separately) at various soil depths and to study the self-serving mechanisms for nitrogen at the ecosystem, providing an appropriate method and season for the application of nitrogen fertilizers. The results obtained in this study were as follows; 1) Of the total nitrogen content of the total tree biomass (except for roots), nearly 61.5% was distributed in the needles, 20% in the branches, 5.5% in the stem bark, and 13% in the stem wood. Therefore, the harvest method of removing only wood parts for pulpwood production has little impact on the self-serving mechanisms of the site's nitrogen status. 2) Inorganic nitrogen concentrations decreased with increasing soil depths. The seasonal average concentration of inorganic nitrogen was highest in early spring and decreased in the following descending order; autumn, tollowed by mid-summer, and early summer. This pattern resulted from the fact that the loss of nitrate was greatly influenced by environmental factors. Thus, it was suggested that an application of active nitrogen fertilizer would be appropriate in spring.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.687-694
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• 2015

The purpose of this study was to evaluate the yield, antioxidant content, and antioxidant activity of adzuki beans according to germination time. Cultivated varieties were Vigna angularis var. Nipponensis cv. Chungju-pat (CJP), and Yeonduchae (YDC), and Vigna radiata (L.) R. Wilczek cv. Dahyeon (DH). The moisture, crude protein, calcium, and magnesium contents of YDC significantly changed with increasing germination time, whereas potassium, natrium, and aluminium contents did not significantly change. Sprout yield, total polyphenol, flavonoid, and tannin contents of ethanolic extracts from adzuki and mung beans significantly increased with increasing germination time. Total polyphenol contents of ungerminated CJP, YDC, and DH were 1.96, 2.68, and 2.02 mg/g, and those of CJP and YDC germinated for 144 h were 3.33 and 3.47 mg/g, respectively. Total flavonoid content of adzuki beans substantially decreased with increasing germination time. Total tannin content substantially increased with increasing germination time, and YDC showed higher contents (0.85 mg/g) sample germinated for 120 h. DPPH radical scavenging activities of CJP and YDC substantially decreased with increasing germination time, whereas that of DH increased. ABTS radical scavenging activities of ungerminated CJP, YDC, and DH were 4.57, 6.51, and 2.82 mg/g, respectively, and increased after germination for 72~120 h.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.85-90
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• 1998

A series of experiments were carried out to determine the effect of seed dressing application of chemicals on the early occurring rice insect pests. The number of small brown planthopper adults per 3hills in seed-dressing plot of Imidacloprid WS (Im WS) was 1.6 and its control efficacy was over 90%, compared with that of untreated plot. Rice water weevil was observed in the density of 8.8 larvae per 5 hills seed-dressed Im WS plots(showing 95.5% of control efficacy). Control efficacy of Im WS and Im GR against adult weevils lasted for 26 days after treatment and was higher than that of Carbofuran GR. Rates of injured stems by rice stem maggot and injured leaves by rice leaf miner were 3% and 3.7% in Im WS treatment plot respectively. Seed germination rate after seed dressing with recommended dosage (3 g/seed kg) of Im WS was 71 % on the 1st day and increased on 5th day up to that of untreated seed. The residual amount of Im in seed dressing plot was 0.11 ppm in rice roots and 0.05 ppm in leaves on the 40th day after treatment. Residual effect of Im WSI sustained for 50 days with over 95% insecticidal effect for the rice water weevil and over 90% for the brown planthopper. Quantity of the chemical applied in the field was calculated as 0.084 kg a.i./ha in seed dressing and 0.3 kg a.i./ha in seed box treatment, respectively It took 1 hour to treat insecticide by seed dressing, 2.5 hours by seed box applying, and 3.6 hours by water surface releasing per 990 $m^2$.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.364-368
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• 2012

In vivo experiments were carried out to investigate the effect of microbial agents on tomato disease occurrences in a sustainable tomato farm in Gong-ju, Chung-nam during 2 years (2010-2011). Two kind of commercial microbial agents (EXTN-1 and Cillus suspension concentrate) and 2 kind of microbial agents (Bacillus subtilis strain 'B4' and 'B17') developing by National academy of agricultural science were used in this study. In the 1st experimental year, the microbial agents were sprayed on leaves for 2-4 times at 1-2 weeks interval from 3 weeks after transplanting, and then disease occurrence were observed. As a result, the control efficacies of commercial EXTN-1 and Cillus suspension concentrate (SC) against gray mold were 59.6% and 50.5% in the treatment of 4 times foliar application at 1 week interval from 3 weeks after transplanting, and the control efficacy of commercial EXTN-1 SC against gray mold was 55.4% in the treatment of 3 times foliar application at 1 week interval from 4 weeks after transplanting. However, the control efficacies of EXTN-1 and Cillus SC were not enough for tomato crop protection against powdery mildew. In the 2nd experimental year, the microbial agents were treated following by the planned combination schedule of transplanting stage drip-watering, early stage root irrigation and early blooming stage foliar application. The control efficacies of EXTN-1 SC and B17 treatment following by transplanting stage drip-watering, 2 times root irrigation at 2 weeks interval root irrigation and 4 times foliar application at 1 weeks interval for gray mold management were 57.0 and 55.1%, respectively. In the case of same treatment for gray mold management mentioned at above, the control efficacies of EXTN-1 SC, B4 and B17 treatment for powdery mildew management were 50.5, 51.3 and 52.5%, respectively.

• Korean Journal of Organic Agriculture
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• v.22 no.2
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• pp.303-319
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• 2014

The study researched germination of the plants and growth of experimented bacteria according to concentration of water extract in order to provide basic data for developing natural agricultural resources by using naturalized plants including Solidago altissima, Amaranthus retroflexus and Sida spinosa. As concentration of water extract increased, most of test plants showed a decrease in relative germinability. Sida spinosa(r=-0.540, p<0.01), Physalis wrightii(r=-0.693, p<0.01), Amaranthus retroflexu(r=-0.724, p<0.01), Solidago altissima(r=-0.728, p<0.01) and Eclipta prostrata(r=-0.779, p<0.01) showed tendency of decrease in relative germinative power in order, respectively. For average germination period, as concentration of the processed group increased, the time for germination increased (r = 0.769, p<0.01) and according to donor plants and test plants, there was a little difference. Also, as concentration of water extract of donor plant, length of above-aerial part(r=-0.587, p<0.01), length of underground part(r=-0.741, p<0.01), fresh weight(r=-0.574, p<0.01) and generation of root hair decreased. An then, for growth of test fungi according to concentration of water extract of donor plants, growths of Botrytis cinerea(r=-0.266, p<0.05), Diaporthe citri(r=-0.323 p<0.01), Colletotrichum gloeosporioides(r=-0.512, p<0.01), Pythiumultimum(r=-0.581, p<0.01) and Rhizoctonia solani(r=-0.806, p<0.01) were repressed in order, respectively. For total amount of content of phenol with herbicidal and Antifungal activities, S. altissima $17.3{\pm}0.5mg/g$, A. retroflexus $13.1{\pm}0.3mg/g$, P. wrightii $12.0{\pm}0.4mg/g$, S. spinosa $9.5{\pm}0.1mg/g$ and E. prostrata L. $4.1{\pm}0.1mg/g$ showed in order, respectively. As these results are summarized, donor plants which were naturalized, have competitive advantage because they release phenolic compounds with allelopathic effect and affect on germination, growth and fungi growth on underground flora compared to native plants and they have eligibility for natural herbicide and germicide.

• Journal of Plant Biotechnology
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• v.32 no.3
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• pp.167-173
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• 2005

Three different cDNAS for cinnamate 4-hydroxylase (C4H) which are involved in the second step of the general phenylpropanoid pathway were isolated and designated as pc4h1 (1,755 bp), pc4h2 (1,655 bp), and pc4h3 (1,316 bp), respectively. The nucleotide sequence analysis revealed that both pc4h1 and pc4h2 clones encode polypeptides of 505 amino acids frame but pc4h3 clone was truncated at the 5'-end of coding region. The alignment of the deduced amino acid sequences showed that PC4H1 and PC4H2 are highly homologous (95.8% identical) with each other and contain three conserved domains which are typical in cytochrome P450 monooxygenase: proline-rich region, threonine-containing binding pocket for the oxygen molecule, and heme binding region. In addition, result of the phylogenic tree analysis revealed that both pepper C4Hs belong to Class 1. pc4h2 transcription was strongly induced in wounded fruit (400%) and root (200%) relative to its very low basal level but not in leaf or stem tissue. In case of pc4h1, the basal level of transcription was higher than pc4h2 but induction by wounding was lower in fruit and root while leaf and stem tissues did not respond to wounding. The basal level of pc4h3 transcripts was not, if any, detectable and response to wounding was not observed.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.242-247
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• 2013

Currently, methods for controlling weeds in organically produced crops have not been as effective as conventional methods. This research was carried out to determine the herbicidal effects of leaf, stem, fruit, root extracts of Trichosanthes kirilowii. The extraction methods used were water, boiling water and ethanol. The characteristics of potential herbicidal components among extraction methods were investigated by using the following solvent fractions: hexane, chloroform, ethyl acetate, butanol, and water. Generally, water extracts provided the best on inhibition of germination rate, plant height, and root length in cucumber and barley. Specifically, extractions made from fruit parts of T. kirilowii provided the greatest inhibition effect on plant growth in cucumber and barely. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fractions, but there were no significant differences among the other fractions. Digitaria siliaris and Solanum nigrum were controlled 80-100% by 5% extractions of water fraction. However, there were no herbicidal effects from foliar treatment in cucumber, barley, black nightshade, and henry crabgrass by 5% extractions of the water fraction. These results show that extractions of T. kirilowii can be used for controlling some weeds in organically produced crops.

• Korean Journal of Organic Agriculture
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• v.13 no.4
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• pp.389-400
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• 2005

This study was conducted to investigate into the ecological environments and the soil microflora of purple-bracted plantain lily (Hosta longipes Matsumura) for wild vgetables. Native soil textures of purple-bracted plantain lily were in the order of sandy loam (SL) > loam (L) > clay loam (CL). pH in soil was relatively acid by 4.8, electric conductivity was 0.08mS/cm, and organic matter content was 0.08g/kg. CEC was measured by $100.8cmol^{(+)}kg^{-1}$ and available phosphate was 103.4mg/kg. Contents of exchangeable cations in terms of potassium, calcium, and magnesium were measured by $0.33cmol^{(+)}kg^{-1},\;2.26cmol^{(+)}kg^{-1},\;and\;0.87cmol^{(+)}kg^{-1}$, etc. Diurnal changes in the air temperature of the natives were 15 to $20^{\circ}C$, that temperature differential was relatively little compared with that in open field by 15 to $30^{\circ}C$. Relative humidity in the natives were much more humid by 60 to 80% compared with that in open feld by 35 to 85%. Light intensity in the natives and the open field at ten o'clock were $2,300{\mu}mol/m^2/sec.\;and\;1,750{\mu}mol/m^2/sec.$ Total number of soil microorganisms were $8.4{\times}10^7\;c.f.u./g$. Mycorrhizal spore densities over $500{\mu}m,\;355{\sim}500{\mu}m,\;251{\sim}354{\mu}m,\;107{\sim}250{\mu}m\;and\;45{\sim}106{\mu}m$ were 0.8, 1.3, 2.1, 38.1, and 110.0 respectively. Mycorrhizal root infections by vesicle and hyphae were 17% and 6%. However, arbuscules in the roots were not shown.