• Journal of Bio-Environment Control
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• v.27 no.1
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• pp.34-39
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• 2018

This research was conducted to estimate moisture content in cucurbitaceae seedlings, such as cucumber and watermelon, using hyperspectral imagery. Using a hyperspectral image acquisition system, the reflectance of leaf area of cucumber and watermelon seedlings was calculated after providing water stress. Then, moisture content in each seedling was measured by using a dry oven. Finally, using reflectance and moisture content, the moisture content estimation models were developed by PLSR analysis. After developing the estimation models, performance of the cucumber showed 0.73 of $R^2$, 1.45% of RMSE, and 1.58% of RE. Performance of the watermelon showed 0.66 of $R^2$, 1.06% of RMSE, and 1.14% of RE. The model performed slightly better after removing one sample from cucumber seedlings as outlier and unnecessary. Hence, the performance of new model for cucumber seedlings showed 0.79 of $R^2$, 1.10% of RMSE, and 1.20% of RE. The model performance combined with all samples showed 0.67 of $R^2$, 1.26% of RMSE, and 1.36% of RE. The model of cucumber showed better performance than the model of watermelon. This is because variables of cucumber are consisted of widely distributed variation, and it affected the performance. Further, accuracy and precision of the cucumber model were increased when an insignificant sample was eliminated from the dataset. Finally, it is considered that both models can be significantly used to estimate moisture content, as gradients of trend line are almost same and intersected. It is considered that the accuracy and precision of the estimating models possibly can be improved, if the models are constructed by using variables with widely distributed variation. The improved models will be utilized as the basis for developing low-priced sensors.

• Applied Biological Chemistry
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• v.38 no.1
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• pp.55-62
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• 1995

To understand the molecular structure of Korean garlic viruses, cDNA cloning of virus genomic RNA was attempted. Virus particles were isolated from virus-infected garlic leaves and a cDNA library was constructed from garlic virus RNA. One of these clones, S81, selected by random sequencing has been identified as a member of potexvirus group other than potyvirus and carlavirus. The clone is 873 bp long contains most of the coat protein (CP) coding region and 3'-noncoding region including poly(A) tail. A putative polyadenylation signal sequence (AAUAAA) and the hexanucleotide motif (ACUUAA), a replicational cis-acting element conserved in the 3'-noncoding region of potexvirus RNAs are noticed. The clone S81 shows about 30-40% identity in both nucleotide and amino acid sequences with CPs of potexviruses. The genome size of the virus was analysed to be 7.46 knt by Northern blot analysis, which was longer than those of other potexviruses. The open reading frame encoding CP was expressed as a fusion protein (S81CP) in Escherichia coli and the recombinant protein was purified by immobilized metal binding affinity chromatography. Polyclonal antibody was raised against S81CP in rabbit to examine the occurrence of garlic potexvirus in Korean garlic plants by immunoblot analysis. Two virus protein bands of Mr 27,000 and 29,000 from garlic leaf extract of various cultivars reacted with the antibody. It was shown that Mr 27,000 band might not be a degradation product of Mr 29,000 band, suggesting that two types of potexvirus different in size of coat protein could exist in Korean garlic plants.

• Korean Journal of Environment and Ecology
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• v.26 no.2
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• pp.219-232
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• 2012

The purpose of this study was to find characteristics of $Pinus$ $densiflora$ forests in previous records and cultural landscape regions and to establish a management method for recovery of $P.$ $densiflora$ landscape. A total of 16 landscape paintings were analyzed to study $P.$ $densiflora$ forests in Inwangsan(Mt.) shown in figure data. As a result of analyzing figure data, $P.$ $densiflora$ $forests$ were found to be distributed mainly in the ridge line of east slope side of Inwangsan(Mt.) from landscape paintings of Jung Seon, Jang Si Heung and Gang Hee Un. In order to analyze the landscape of $P.$ $densiflora$ forests shown in photograph data on Inwangsan(Mt.), photographs of Inwangsan(Mt.) since late 1800s were searched and a total of 24 photographs were used for analysis. As a result of photographic analysis, $P.$ $densiflora$ forests were found to be distributed mainly in the low area and ridge line of western slope side of Inwangsan(Mt.). As a result of analyzing the distribution status of 10 cultural heritages of Inwangsan(Mt.), cultural heritages in the mountain were mainly established with rocks and $P.$ $densiflora$ forests as the background and are establishing their landscape not only as a form of cultural heritage but also including the natural landscape in the background. A method of restoring cultural landscape of P. densiflora forests was necessary. As a result of analyzing 26 rock beds of Inwangsan(Mt.), most of $P.$ $densiflora$ forests were distributed nearby rock beds since the past. Among such regions, restoration and management of introduced species in the accumulated soil regions to $P.$ $densiflora$ forests were deemed necessary. As a result of analyzing current vegetation of $P.$ $densiflora$ forest areas of the past, 51.87% of areas maintained $P.$ $densiflora$ forest and 25.80% were changed to artificial forests. Most of low areas of the mountain were turned into urban area (10.16%). Management type for restoration of $P.$ $densiflora$ landscape of Inwangsan(Mt.) was classified into preservation, $P.$ $densiflora$ restoration and maintenance. Preservation management was configured as $P.$ $densiflora$ distribution and rocky area distribution. The targets of $P.$ $densiflora$ restoration were indigenous broad-leaf trees, vegetation areas with introduced species and damaged regions within the mountain. The targets of maintenance were urban area in the low area of Inwangsan(Mt.) and military base at the top of the mountain.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.490-495
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• 2013

Two chrysanthemum varieties, 'ARTI-purple' and 'ARTI-queen', were chronically irradiated with doses of 30, 50, 70, and 100 Gy for four weeks in gamma-phytotron, a long term irradiation facility. We investigated the growth, responses of antioxidant enzymes (ascorbate peroxidase, APX; catalase, CAT; peroxidase, POD; superoxidase dismutase, SOD) and malondialdehyde (MDA) contents under different doses of chronic-irradiation. The five plant growth measurements including plant height, number of leaves, internode length, stalk diameter and leaf thickness were investigated immediately after four week irradiation. The plant height (p<0.001), internode length (p<0.01), the number of leaves (p<0.001) and stalk diameter (p<0.05) were significantly decreased an increasing doses of gamma-ray. Among them, especially, the internode length was remarkably decreased showing the RD50 (Reduction Dose 50) at approximately 65 Gy. The antioxidant response after four weeks of recovery period, ascorbate peroxidase (APX) (p<0.01), superoxide dismutase (SOD) (p<0.01) and peroxidase (POD) (p<0.001) were significantly increased with an increasing dose of gamma-ray. And malondialdehyde (MDA) (p<0.01) contents showed the significant increase at the 70 and 100 Gy which means the oxidative stress was lasting for a considerable period. In this study, the 50 Gy irradiation as optimal dose showed higher growth than the $RD_{50}$, it also showed insignificant differences on the antioxidant responses and MDA contents. However, the 100 Gy dose showed lower growth than $RD_{50}$.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.235-244
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• 2004

In this study, we compared the levels of methylotrophic bacterial community diversity in the leaf samples of 19 rice cultivars collected from three regions of Korea. Nineteen pink pigmented isolates showing characteristic growth on methanol were obtained. Physiological and biochemical characters of each isolate were examined according to methods described in Bergey's Manual of Systematic Bacteriology. When phylotypes were defined by performing numerical analysis of 37 characteristics, four distinct clusters were formed. The two reference strains, Methylobacterium extorquens AM1 and Methylobacterium fujisawaense KACC10744 were found to group under cluster IV and cluster III respectively. Cluster I diverged on the basis of nitrate reduction and four isolates showed tolerance upto 0.5 M NaCl concentrations. Two strains in cluster I and III were found to possess methane utilizing properties. Most of the isolates in all the four clusters utilized monosaccharides, disaccharide and polyols as carbon source. When the isolates were subjected for indole-3-acetic acid (IAA) analysis in the presence of L-tryptophan, only 8 isolates exhibited IAA production. In addition, the nitrogen source in the medium was found to influence the IAA production. Addition of $(NH_4)_2SO_4$ in the medium led to a 2 to 30 fold increase in the indole synthesis. However, $KNO_3$, $NH_4NO_3$ and $NH_4Cl$ substitution did not significantly stimulate the synthesis of IAA in the growth medium. Result of gnotobiotic root elongation assay significantly increased roots and shoots lengths, and number of lateral roots, which is mediated by IAA production in the culture medium. The rice seedlings primary roots from seeds treated with methylotrophic isolates were on average 27 to 56% longer than the roots from seeds treated with the uninoculated seeds. In addition, application of different high concentrations of authentic IAA ($400g\;mL^{-1}$) to roots of rice seedlings inhibited root growth. However, the IAA concentration from 10 to $200g\;mL^{-1}$, IAA promoted root growth of rice seedlings. These results suggest that bacterial IAA plays a major role in the development of the host plant root system.

• 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 Plant Biotechnology
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• v.30 no.1
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• pp.13-18
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• 2003

This study was carried out to investigate the expression patterns of foreign gene that controlled by tuber-specific patatin promoter in transgenic potatoes. Potato leaf disc cultured in vitro were transformed by the Agrobacterium strain LBA4404 containing pBl121 or pATGUS from potato cv. Desiree. In order to select the transgenic lines, gene-specific primers deduced from the NPTII were synthesized and used for polymerase chain reaction. The down part of the putative transgenic potatoes was transplanted weekly onto sucrose-enriched medium to accelerate the microtuber formation. RNA gel blot analysis was performed on the total RNAs obtained from tuber that had been harvested at a week interval. Also, histochemical assay was observed in the explants transformed with either pBI121 or pATGUS. Results showed that the transgenic plant containing pATGUS expressed GUS transcripts mainly at the tuber, not in stem, with the highest expression level in 5 weeks-grown microtubers. In contrast to pATGUS plants, the transformed plants with pBI121 showed an equal expression pattern throughout the whole developing stages. Consistent with RNA gel blot analysis, histochemical GUS staining and enzyme activity exhibited pATGUS transcripts were at the highest level in 5 weeks cultures. From these results, we suggest that the best stage to analyze the foreign gene introduced by patatin promoter into potato plants is at 5 weeks cultures after tuber formation.

• Food Science and Preservation
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• v.20 no.3
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• pp.323-329
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• 2013

Strawberries are among the leading ready-to-eat agricultural products that have superior taste and nutrition. Thus, consumer concerns about the safety of eating strawberries are growing. To evaluate the contamination levels of strawberries according to their cultivation methods (nutriculture, pesticide-free culture and organic farming) and parts [fruit (flesh), stalk (pedunle) and leaf (calyx)], 1,020 parts of strawberry samples were collected at 12 farms in Nonsan-si and quantitatively or qualitatively examined for the indicators of food safety and food poisoning bacteria. The total aerobic bacteria count in the whole samples was 2.3~6.8 ${\log}_{10}$ CFU/g, and coliform bacteria were detected in 14.2% of the whole samples with a contamination level range of 2.1~4.5 log CFU/g. E. coli were detected in 0.9% of the whole samples with a contamination level range of 2.1~2.8 log CFU/g. The analysis of the bacterial levels according to the cultivation methods showed that the total aerobic bacteria and coliform counts were higher in the strawberries that were grown via organic farming than in those that were grown via nutriculture and pesticide-free culture. However, the E. coli counts of the strawberries that were grown via organic farming and via pesticide-free culture were similar and differed from that of the strawberries that were grown via nutriculture. The analysis of the contamination levels according to the parts of the strawberries showed that the total aerobic bacteria, coliform and E. coli counts of the fruits, stalks and leaves of the strawberries did not significantly differ. Staphylococcus aureus was detected in two organically grown strawberries, but Salmonella spp., Listeria monocytogenes and E. coli O157:H7 were not detected in the whole samples. These results show that the bacterial contamination levels of the strawberries differed based on their cultivation methods. Thus, a suitable method of reducing the bacterial contamination levels of strawberries according to their farming methods is needed.

• Korean Journal of Plant Resources
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• v.29 no.1
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• pp.62-89
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• 2016

The great part of the traditional knowledge on ethnobotanical plants and their uses is gradually vanishing due to industrialization, therefore ethnobotanical studies that explore and preserve the knowledge are in urgent needed before the knowledge are lost ever. This study was conducted to record and conserve the traditional knowledge of botanical taxa in Korea from 2006 to 2014. According to the survey results, derived from 17,328 sheets of 1,771 residents at 868 places, the ethnobotanical plants in Korea consisted of a total 924 taxa; 130 families, 493 genera, 813 species, 7 subspecies, 92 varieties and 12 form. Of them, herbs were 619 taxa (67.0%) and woody plants were 305 taxa (33.0%). 707 taxa (76.5%) out of 924 taxa grow wild, 44 taxa (4.8%) were cultivated wild species, 145 taxa (15.7%) were introduced for cultivation, and 28 taxa (3.0%) were naturalized plants. The analysis of usage for 924 taxa showed that the edible use was the highest with 58.9%, followed by medicinal with 26.9%, material with 3.7% and ornamental with 2.3%, respectively. The leaf of plant was the most useful part, followed by stem and root. Quantitative analysis of the ethnobotanical plants in Korea was performed by the basic values of FC, NU and UR, and indices of CI, RFC, RI and CV. As a result, The CI place Artemisia princeps in first position, followed by Aster scaber, Kalopanax septemlobus. The RFC place A. scaber in first position, followed by A. princeps, Aralia elata. The RI place A. princeps in first position, followed by Pinus densiflora, Morus alba. The CV place A. princeps in first position, followed by P. densiflora, K. septemlobus.

• Journal of Korean Society of Forest Science
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• v.77 no.3
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• pp.338-350
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• 1988

In order to solve the taxonomic problems of the genus Juniperus growing in South Korea, an identification key of the genus and species was developed bayed un flower structure, cane and seed shape, branching habit, tree form, leaf characteristics etc. of the 7 native species and the a exotic cultivars. The typical pattern of karyotype found by chromosome analysis of the species was used for the identification among morphologically similar species. The length of chromosome were ranged $9{\sim}15{\mu}m$ in all studied specie. J. chinensis, var. procumbens, and var. kaizuka sere tetraploid, 4n=44, var. globosa, var. procumbens, var. horizontalis, J. virginiada, J. rigida, J. rigida var. longicarpa, and J. coreana were diploid, 2n=22. The species in the Sabina section showed large variation in the length of chromosome and kinetochore position. The species in the Oxycedrus section showed the cytological characteristics that the 11th chromosome t-type(acrocentric), and the m-type abundant chromosome set was relatively uniform as compared to those of the Sabina section. The species in the Sabina section, which are planted in the large city area, show great morphological variation because many different ecotypes were mixed and often crossed among them. In summary, this study was able to make clear identification and to find out similarity among Juniperus, species by the morphological and cytological analysis.