• Journal of Plant Biology
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• v.29 no.2
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• pp.85-94
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• 1986

Canavanine content of the cotyledons of Canavalia lineata decreased gradually during germination and growth of seedlings but continued to increase in roots and leaves. After abscission of cotyledons, canavanine content of leaves depleted competely. The activity of canavanase could be detected in leaves and roots, but not in cotyledons. High arginase activity was observed in the cotyledons of seeds at the earlyimbibition period. During the growth of seedlings, cotyledonary canavanine appeared to be transported to the growing of seedlings where it could be utilized through nitrogen metabolic pathways. In crude cell-free extracts of leaves, maximum activities of canavanase or arginase appeared in 30mM Tris-HCl buffer (pH 9.0) or 30mM NaHCO3 buffer (pH 10.0), respectively. The activities of these two enzymes differed from each other when treated with Co2+ or Mn2+. These results support the idea that canavanase and arginase might be different enzymes.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.125-130
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• 2008

Various kinds of leaf spots and blights were found in kiwifruit (Actinidia deliciosa) orchards on 2006 in Korea. Disease incidences were quite variable between open-field and rain-proof shelter. Rate of diseased leaves was recorded as about 70% at open-field orchards in late season but use of rain-proof vinyl shelters alleviated the disease incidences by 20%. Angular leaf spots appeared at early infection stage on June and several other symptoms were also recognized as the disease developed afterward. On September, brown leaf blights were the most frequent, followed by grayish brown ring spots, silvering gray leaf blights, zonate leaf blights, dark brown ring spots and angular leaf spots at open-field orchards. Four fungal species were frequently isolated from the disease symptoms. Phomopsis sp. was the most predominant fungus associated with the leaf spot and blight symptoms on kiwifruit, followed by Glomerella cingulata, Alternaria alternata and Pestalo-tiopsis sp. Phomopsis sp. was commonly isolated from angular leaf spots, silvering gray leaf blights, and zonate brown leaf blights. G. cingulata, A. alternata and Pestalotiopsis sp. were isolated from grayish brown ring spots (anthracnose), brown ring spots and zonate dark brown leaf blights. Typical symptoms appeared on the wounded and unwounded leaves, which were inoculated by each of Phomopsis sp., G. cingulata, and Pestalotiopsis sp., but A. alternata caused symptoms only on the wounded leaves.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.90.1-90
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• 2003

Colonization of Pseudomonas chlororaphis O6, a nonpathogenic rhizobacterium, on the roots induced systemic resistance in cucumber plants against tai-get leaf spot, a foliar disease caused by Corynespora cassiicola. A cDNA library was constructed using mRNA extracted from the cucumber leaves 12 h after inoculation with C. cassiicola, which roots had been previously treated with O6. To identify the genes involved in the O6-mediated induced systemic resistance (ISR), we employed a subtractive hybridization method using mRNAs extracted from C cassiicola-inoculated cucumber leaves with and without previous O6 treatment on the plant roots. Differential screening of the cDNA library led to the isolation of 5 distinct genesencoding a GTP-binding protein, a putative senescence-associated protein, a galactinol synthase, a hypersensitive-induced reaction protein, and a putative aquaporin. Expressions of these genes are not induced by O6 colonization alone. Before challenge inoculation, no increase in the gene transcriptions could be detected in previously O6-treated and untreated plants but, upon subsequent inoculation with the pathogenic fungus, transcription levels in O6-treated plants rose significantly faster and stronger than in untreated plants. Therefore, the O6-mediated ISR may be associated with an enhanced capacity for the rapid and effective activation of cellular defense responses which becomes apparent only after challenge inoculation on the distal, untreated plant parts, as suggested by Conrath et al. (2002). This work was supported by a grant R11-2001-092-02006-0 from the Korea Science and Engineering Foundation through the Agricultural Plant Stress Research Center at Chonnam National University.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.252-260
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• 2014

Contents of carotenoids, phenolic compounds, volatile organic compounds, and alkaloids in leaves, internodes, fruits, and roots of tomatoes in different developmental stages were measured. Lycopene, ${\beta}$-carotene, and lutein were detected in all the tested parts except roots and green fruits. Lycopene content in red fruits was $49.04{\mu}g{\cdot}g^{-1}$ FW, while that in the other parts was below $40{\mu}g{\cdot}g^{-1}$ FW. ${\beta}$-Carotene and lutein contents in 24th leaves were 5.81 and $6.40{\mu}g{\cdot}g^{-1}$ FW, respectively, and were greater than those in the other parts. Caffeic, chlorogenic, and vanillic acids were detected in all the tested parts except roots. The content of chlorogenic acid in the 18th leaves was $40.11{\mu}g{\cdot}g^{-1}$ FW, while that in the other parts was lower than $31.00{\mu}g{\cdot}g^{-1}$ FW. The contents of caffeic and vanillic acids in the 24th leaves were 9.18 and $1.64{\mu}g{\cdot}g^{-1}$ FW, respectively, and were greater than those in the other parts. Moreover, younger leaves contained the more diverse volatile organic compounds including monoterpenes and sesquiterpenes. Contents of dehydro-tomatine and ${\alpha}$-tomatine were greatest in leaves, followed by internodes, roots and fruits. Younger leaves and internodes contained more dehydro-tomatine and ${\alpha}$-tomatine than older leaves and internodes. The contents of dehydro-tomatine and ${\alpha}$-tomatine in the 24th leaves were 0.89 and $1.42mg{\cdot}g^{-1}$ FW, respectively, and were greatest among all the tested parts. Our results indicated that, except lycopene, tomato leaves included greater secondary metabolites contents than red fruits. The results suggest that inedible parts of tomato plants can be used as raw material for antioxidants, anti-inflammatory agents, fungistats, and pesticides.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.371-381
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• 2023

The effectiveness of plant-based attractants was studied using large traps, which attracted relatively more snails in agricultural water drainage ditches and rice-cultivating environments, although their effectiveness in rice fields and lakes was limited. The rate began to rise after three hours of observation. Watermelon peel exhibited the highest apple snail attraction rate (13.8%), followed by potatoes (10.0%), and apple peel (8.8%). These values significantly differed from the attraction rate attributed to papaya leaves (F=3.84; P=0.0387). After 24 h, watermelon peel and apple peel indicated a higher rate of attraction (23.4% and 21.7%, respectively), which were significantly different compared with those of papaya leaves and potatoes (F=9.94; P=0.00455). Large bait traps outperformed funnel traps in capturing golden apple snails and trapped a significant number of snails measuring over 1 cm in size. Watermelon peel was the most effective attractant for a large bait trap, followed by apple peel, potatoes, and papaya leaves. On average, 110 snails were captured in the lure net. However, potatoes, apple peels, and papaya leaves caught an average of 93, 80, and 79 snails, respectively. Among the attractants, the lure effect of the snails was not significantly different. The efficiency of large bait traps in capturing snails, regardless of the plant attractant employed, followed the order: apple peel > watermelon peel and potatoes > papaya leaves > melon > Korean melon. Watermelon peel is highly recommended for farmer use, as well as apple peel and potatoes. Utilizing these snail attractants may contribute positively to developing a safe and environment-friendly integrated pest management strategy.

• Agricultural and Biosystems Engineering
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• v.7 no.1
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• pp.27-41
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• 2006

Assessment of nitrogen and chlorophyll content from crop leaves can help growers adjust N fertilizer rates to meet the demands of the crop. Numerous researchers have presented their studies about spectral signature of plant leaves to characterize the plant features. However, interrelational review and summary were limited and a communication gap exists between the plant science and optical engineering. Understanding the mechanism of leaf interaction to electromagnetic radiation and factors affecting spectrophotometric measurements can enhance the foundation of optical remote sensing technologies. This paper provides extensive review of previous works in optical sensing and explains the basics of plant optics, spectral measurements for plant stress, factors that affect sensitivity to spectral analysis, and applications that deploy optical remote sensing technologies.

• Journal of Photoscience
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• v.9 no.2
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• pp.391-393
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• 2002

Effects of illumination with xenon or sulfur lamp on growth of tomato seedlings were studied. Results showed no obvious differences in net photosynthetic rate and apparent quantum efficiency. In comparison with xenon lamp, illumination with sulfur lamp slightly reduced ChI a and ChI b content in leaves, relatively shortened epicotyl and hypocotyl length, but significantly increased anthocyanin content of leaves and promoted root growth of tomato seedling plants.

• Korean Journal of Plant Taxonomy
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• v.44 no.3
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• pp.188-190
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• 2014

The unrecorded plant, Aster hispidus var. leptocladus (Compositae), was reported from Mt. Palgong-san, Daegu-si, Korea and was named as 'Gin-ssuk-bu-jaeng-i' after its slender leaves. It is distinguished from var. hispidus by having glabrous linear cauline leaves with acute apex, small heads and involucre, short pappus in disc florets. It had been considered as Japanese endemic plant especially adapted to serpentine area.

• Korean Journal of Plant Resources
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• v.29 no.6
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• pp.642-649
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• 2016

This study was conducted to investigate the antioxidant activity in the leaves and stems of 50 tomato accessions, in order to examine the possibility of using tomato by-products as a functional material. The extracts of the leaves (LE) and stems (SE) were analyzed for DPPH, ABTS, and total polyphenol content (TPC). Antioxidant activities and TPC differed significantly between the LE and SE of the 50 tomato accessions. TPC in LE and SE showed wide variation, ranging from 24.4 to 60.6 and 12.5 to 18.8 mg GAE/g, respectively. The DPPH and ABTS antioxidant activities of LE ranged from 10.0 to 38.2% (scavenging effect) and 20.8 to 59.0 mg ASC/g, respectively, while the DPPH and ABTS measurements of SE were 1.4 to 8.8% and 2.2 to 22.5 mg ASC/g, respectively. As assessed by the relative antioxidant capacity index (RACI), IT033117 and IT203466 had the highest antioxidant activity in LE and SE, respectively. These results will expand the knowledge of antioxidant activity and provide information on tomato accessions valuable for the development of functional foods and food additives.

• Korean Journal of Environmental Biology
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• v.17 no.3
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• pp.371-378
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• 1999

Morphology and karyotype of Korean Convallaria majalis plants were observed for taxonomic studies. Most plants produced two leaves (70%) and some one leaf (30%), but rarely three leaves. Plant length averaged 34.4 $\pm$ 4.6 cm. Percentage of plants bearing flowers was very low with 3.7% (n=1,346) in the field. Raceme usually grew below leaves and rarely grew over leaves. Plant beared five to ten flowers on a single raceme. Chromosomes were x=19 and diploidy with 2n=38. The chromosomes were composed of 13 pairs of median and 6 pairs of submedian chromosomes. The number of chromosome and karyotype of Korean C. majalis plant agree with those of Japanese and European plants.