• Horticultural Science & Technology
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• v.32 no.6
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• pp.762-770
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• 2014

This study was conducted to elucidate the influence of prohexadione-calcium (Pro-Ca) application on shoot growth and fruit quality in 'Fuji'/M.9 mature apple trees. Pro-Ca was applied at concentrations ranging from 100 to $400mg{\cdot}L^{-1}$ one time at petal fall (PF; 5-10 cm terminal shoot growth) to the whole canopy of the tree, or at 100, 125, $150mg{\cdot}L^{-1}$ concentrations two times, at PF and then 4-8 weeks after PF. Pro-Ca treatment generally reduced mean shoot growth, with its effect being proportional to the application rate. Pro-Ca at $400mg{\cdot}L^{-1}$ significantly reduced the shoot growth by 15-22% compared to the control, while its effect was not significantly different from Pro-Ca $200mg{\cdot}L^{-1}$. Pro-Ca treatments induced higher occurrence of secondary growth compared to the control. Pro-Ca treatment increased the photosynthetic rate by 5-10% relative to the control, and also increased soluble solid concentration and fruit red color. However, fruit weight was significantly reduced by $400mg{\cdot}L^{-1}$ Pro-Ca, which was attributable to the greater secondary growth caused Pro-Ca $400mg{\cdot}L^{-1}$ treatment compared to the control and Pro-Ca $200mg{\cdot}L^{-1}$ treatment.

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.93-100
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• 2005

This research was performed to investigate the possibilities of industrial usage of camellia (Camellia japonica L.) by examining the antioxidant and antimicrobial effects of methanol extract with different sections. Content of total phenolics, DPPH radical scavenging activities and antibacterial activity of young leaf, mature leaf, flower bud, flower, bark, and seed of camellia were compared in vitro experimental models. Total phenolics was contained the higher in young leaf (74.62 mg), flower bud (65.02 mg) and flower (62.42 mg) but less than 20.95 mg per 100 g of dry weight in other parts of Camellia japonica L. And effects of antioxidant measured by DPPH radical scavenger activity ($RC_{50}$, reduce concentration 50%), was shown higher $7.16{\sim}18.14\;{\mu}g/m{\ell}$ in methanol extract of young leaf, flower bud and flower than $61.23\;{\mu}g/m{\ell}$ of BHT as a chemical oxidant. Also, the antimicrobial activity of Camellia japonica L. extracts determined using a paper disc method against food-borne pathogen and food spoilage bacteria, the young leaves extracts showed the most active antimicrobial activity against 7 kinds of harmful microorganisms. Flower bud extracts showed the highest antibacterial activity against P. aeruginosa and Enterobacter spp. C1036. In addition, the minimum inhibitory concentration (MIC) of young leaf extract against B. subtillis,S. fradiae,S. aureus,E. coli,P. aeruginosa, Enterobacter spp. C1036, and S. typhimurium were revealed 1 to 15 ${\mu}g/m{\ell}$. As a result, antimicrobial activity of camellia extracts was shown higher gram positive bacteria than gram negative bacteria.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.11-18
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• 1996

A greenhouse experiment on the Sr-90 uptake by peanut and sesame was conducted through pot cultures on a sandy loam soil of pH 6.35 treated with Sr-90 in 5.2 and 31.2Bq per gram. The rate of Sr-90 transfer from soil to each plant part, the ratio of Sr-90 concentration in the part to the concentration in soil, and the patterns of their temporal changes were not, on the whole, significantly different between the two treatments. About 0.7 and 0.5 % of Sr-90 in soil transferred to all the mature plants of peanut and sesame, respectively, with the radioactivities in their roots not counted. Only 4% and less than 15% of Sr-90 absorbed by peanut and sesame, respectively, translocated to their seeds. Both crops showed the highest Sr-90 concentration in the leaf and the lowest in the seed. At maturities, the concentration ratio in dry seed was 0.4 in peanut and 3.3 in sesame and that in dry leaf was 12.5 and 10.7, respectively. Sr-90 concentrations in the top 15 cm soil after harvests averaged about 80 % of the concentrations at starting. Sr-90 uptake resulted in neither growth inhibition nor yield decrease.

• Korean journal of applied entomology
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• v.33 no.2
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• pp.60-65
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• 1994

This study was carried out to investigate the ecology of Nesodiprion japonlcus (Mmm,m) damaging many conifers The results obtained were as follows: Nesod~prion japonicus (Maun) emerged two times for a year and their body was black m both sexes. A female (10.1t 1 2 mm) adult was larger than a male (9.9t 0.8 mm) one in the body size. The size of antenna as plumose of female was different from that of male. Life span of adults was 3 or 4 days, those emergence rate was 92% and sex ratio of female to male was 6: 4. Adults 1a1d only an egg in the leaf and the region of the leaf aviposited turned brown. Duration of egg was 14.35 1 2 days, egg was In the shape of banana and red~sh-yellow,a nd its sire was 2.4+ 0.2 mm long. Duration of larvae was 30.35 2.1 days and its slze 20.15 2.2 mm, body was green with grey~sh shipes on the dorsal and lateral aspect, the tip of front and hind was yellow and head was brown with a dark-p~gmented area. Mature larva turned into light green and get lost a dark-pigmented area of head. The firstly-emerged larva made cocoons on the base of leaves and the secondawemerged larva among fallen leaves Duration of prepupa was 14.3f 2.0 days and their size 10.15 2.3 mm Duration of pupa was 12.2+ 1.3 days and its size 10.lt0.2mm.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.143-150
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• 2009

Deicing salt is used to melt snow and ice on the road for traffic safety during the winter season, which accumulates in the roadside vegetation and induces visible injuries. The damage may accelerate particularly when it coincides with early spring leaf out. In order to better understand the response mechanisms, C. kousa (3-year-old) was irrigated twice prior to leaf bud in a rhizosphere with solutions of 0.5, 1.0, and 3.0% calcium chloride ($CaCl_2$) concentration, that were made by using an industrial $CaCl_2$ reagent practical deicing material in Seoul. Physiological traits of the mature leaves were progressively reduced by $CaCl_2$ treatment, resulting in reductions of total chlorophyll contents, chlorophyll a:b, photosynthetic rate, quantum yield, stomatal conductance, $F_V/F_M$, and NPQ. On the contrary, light compensation point and dark respiration were increased at high $CaCl_2$ concentration. A decrease in intercellular $CO_2$ concentration by stomatal closure first resulted in a reduced photosynthetic rate and then was accompanied by low substance metabolic rates and photochemical damage. Based on the reduction of physiological activities at all treatments ($CaCl_2$ 0.5%, 1.0%, and 3.0%), C. kousa was determined as one of the sensitive species to $CaCl_2$.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.27-27
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• 2015

Clubroot (Plasmodiophora brassicae) is a serious agricultural problem affecting Brassica crop production worldwide. It also infects the model plant Arabidopsis thaliana. During infection, this biotrophic pathogen manipulates the development and metabolism of its host leading to the development of galls in the root and hypocotyl. In turn, its own development is strongly influenced by the host. The aim of this study is to investigate the metabolism of clubroot-infected plants using a combination of transcriptomic and metabolomic approaches. We have used direct injection mass spectrometry to obtain a metabolic fingerprint of when changes in the metabolome occur and linked this with changes in host and pathogen gene expression. We have identified alterations in carbohydrate metabolism that occur during P. brassicae infection of A. thaliana plants. Transcriptomic analysis showed that host genes associated with sugar transport and metabolism were induced during gall formation and that the pathogen also expresses genes associated with these processes. We have examined the impact of inactivating host sucrose synthase, cytosolic invertase and sugar permeases on gall formation, identifying host genes that are required for gall formation. We have also explored how sugar status is changed in root tissue, developing and mature leaf during infection of wild type and mutant plants.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.77-82
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• 1998

Aerenchyma development in rice (Oryza sativa L.) roots is quite important for adaptation to waterlogged or reduced soil conditions. Anatomical observations were carried out to clarify the development of schizogenous and lysigenous aerenchyma in elongating crown roots of rice. The crown roots of 3rd and 4th phytomer were taken from rice plants of the 8th leaf stage grown by hydroponic culture. The schizogenous intercellular spaces in the cortex of crown root tip were observed using a light microscope with semi ultra-thin sections and the lysigenous aerenchyma in mature tissue of crown root were observed using a cryo scanning electron microscope (cryo-SEM) with freezing fracture method. The schizogenous intercellular spaces in the root tip exist obviously in the middle portion of cortical cell layers close to the root-root cap junction, but not in root cap, stele and outer cell layers of cortex. The air spaces were formed at the junction of four neighbouring cells of inner cortex in the transverse sections, and between longitudinal cell layer connected along the root axis. Although many of those spaces were filled with liquid, some spaces seem to exist as air spaces. The lysigenous aerenchyma in the cortex, which hardly filled with liquid, emerged at 3-4 cm segment from the root tip and increased toward the basal region of root axis. The developing process of lysigenous aerenchyma was primarily separation of a radial row of cells caused by the shrinking and collapsing of cortical cells and then formation of septa along the radial cell rows by the fusion of cell wall with each other. These results suggest that the schizogenous and lysigenous aerenchyma playa role as a passage for the movement of oxygen into the root tip region where oxygen is required for respiration.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.86-92
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• 1992

Green buckwheat seedlings have been used as a pollution free vegetable and medicinal crop for a long time. Some of the reasons are the rapid growth rate, the high protein and rutincontent, and a more favorable ratio of leaf to stem than mature plants. Off-crop season cultivation techniques were developed for growing the young and green buckwheat vegetable of higher quality and yield, and for its increased value-added income. The effects of planting season, seeding rate, seed bed soil fertility and type, and seedling growth period on yield and rutin content were determined for vegetable and medicinal use. The young vegetable yields. in the off season culture ranged from 2.62t/ha to 22.7t /ha. The highest vegetable yield was 22.7t /ha for 25 days old seedlings grown in the polyethylene film tunnel from March 30 to April 25, 1991 where seedling rate was 360kg /ha. Buckwheat vegetable quality and income were dependent upon planting season, seeding rate, growing duration and temperature, and facilities of raising seedlings. Protein content of buck-wheat seedlings was from 21.5% to 17.2%. Rutin content of the vegetable was 53.9～31.7mg /100g for the whole plant in average. The protein and rutin content was significantly varied due to the different environmental conditions including fertility and type of seed bed soil, growing duration, temperature of the green house, and polyethylene film house and tunnel.

• BMB Reports
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• v.42 no.10
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• pp.673-678
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• 2009

The cDNA of alcohol dehydrogenase (PgADH) was isolated and characterized from the leaf of Panax ginseng. The cDNA had an open reading frame of 801 bp and a deduced amino acid sequence of 266 residues. The calculated molecular mass of the mature protein is approximately 29 kDa with a predicated isoelectric point of 6.84. Homology analysis revealed that the deduced amino acid of PgADH shares a high degree of homology with the short-chain ADH proteins of other plants. Genomic DNA hybridization analysis indicated that PgADH represents a multi-gene family. The expression of PgADH under various environmental stresses was analyzed at different time points using real-time PCR. ABA, SA and especially JA (80-fold) significantly induced PgADH expression within 24 h of treatment. The positive responses of PgADH to abiotic stimuli suggest that ginseng ADH may protect against hormone-related environmental stresses.

• BMB Reports
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• v.41 no.3
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• pp.259-265
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• 2008

Three peroxidase (POD) cDNAs were isolated from dehydration-treated fibrous roots of sweetpotato (Ipomoea batatas) plant via the screening of a cDNA library, and their expressions were assessed to characterize functions of each POD in relation to environmental stress. Three PODs were divided into two groups, designated the basic PODs (swpb4, swpb5) and the anionic PODs (swpa7), on the basis of the pI values of mature proteins. Fluorescence microscope analysis indicated that three PODs are secreted into the extracellular space. RT-PCR analysis revealed that POD genes have diverse expression patterns in a variety of plant tissues. Swpb4 was abundantly expressed in stem tissues, whereas the expression levels of swpb5 and swpa7 transcripts were high in fibrous and thick pigmented roots. Swpb4 and swpa7 showed abundant expression levels in suspension cultured cells. Three POD genes responded differently in the leaf and fibrous roots in response to a variety of stresses including dehydration, temperature stress, stress-associated chemicals, and pathogenic bacteria.