• Journal of Bio-Environment Control
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• v.9 no.3
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• pp.171-178
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• 2000

Gross photosynthetic rats of leaves of hydroponically grown cucumber plants(Cucumis sativus L. cv. Guwoosalichungjang) were measured under various conditions of photosynthetic photon flux(PPF), ambient $CO_2$ concentration, air temperature and leaf nitrogen contents. Light compensation point of leaf photosynthesis appeared to be in the range of 10~20$\mu$mol.m$^{-2}$ .s$^{-1}$ and light saturation point be above 1000$\mu$mol.m$^{-2}$ .s$^{-1}$ . Gross photosynthetic rates increased persistently and asymptotically as air temperature rose from 12$^{\circ}C$ to 32$^{\circ}C$. However, there were only small differences in gross photosynthetic rates in the range of 24-32$^{\circ}C$, so that the range seemed to be optimal for photosynthesis of cucumber plants at the condition of $CO_2$ concentration of 400$\mu$mol.mol$^{-1}$ and PPF of around 400$\mu$mol.m$^{-2}$ .s$^{-1}$ . $CO_2$ compensation point of leaf photosynthesis appeared to be in the range of 20-40$\mu$mol.mol$^{-1}$ and $CO_2$ saturation point be above 1200$\mu$mol.mol$^{-1}$ . Gross photosynthetic rates increased sigmoidally as leaf nitrogen content increased. These environmental factors interacted synergistically to enhance gross photosynthetic rate, so that the rate increased multiplicatively s level of one factor increased progressively with higher levels of he other factors. Mathematical models wer developed to estimate the gross photosynthetic rate in accordance with the variations of these environmental factors. These modes can be used not only to explain he variation of growth or yield of cucumber plants under different environmental conditions but also as building blocks of plant growth model or expert system of cucumber plants.

• Research in Plant Disease
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• v.21 no.3
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• pp.186-192
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• 2015

Cucumber mosaic virus possesses 2b gene known as a suppressor of post-transcriptional gene silencing (PTGS). To investigate its function and effect in plant, transgenic Nicotiana benethamiana expressing 2b gene was developed and analyzed in phenotypic characteristics and differential gene expression (DEG) comparing with wild-type. Eight lines of transgenic plants ($T_0$) were obtained with difficulty and showed severe deformed phenotypes in leaves, flowers, petioles and etc. Moreover, transgenic plants were hardly able to set seeds, but small amounts of seeds were barely produced in some of transgene-hemizygous plants. DEG analysis showed that transgenic plant ectopically accumulated diverse RNA transcripts at higher levels than wild-type probably due to the disturbance in RNA metabolism, especially of RNA decay, caused by 2b-mediated inhibition of PTGS. These ectopic accumulations of RNAs disrupt protein and RNA homeostasis and then subsequently lead to abnormal phenotypes of transgenic plants.

• Journal of Plant Biotechnology
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• v.2 no.1
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• pp.51-54
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• 2000

Leaf explants of the cucumber (Cucumis sativus L.) were cultured on Murashige and Skoog's (MS) medium supplemented with various concentrations of $\alpha$-naphthalene acetic acid (NAA) and 6-benzylaminopurine (BAP). Direct shoot orgnogenesis as well as callus formation with somatic embryos and multiple shoots was observed from leaf explants of cvs. Shinhukjinju and Chungjang. The highest frequency of shoot formation 80% was observed on MS medium supplemented with NAA/BAP (5.0 ${\mu}{\textrm}{m}$/2.5 ${\mu}{\textrm}{m}$), with explants forming 3-7 shoots. Shoots formation occured within 3 to 4 weeks. Only one subculture of calli was required for plant regeneration on normal growth regulator-free medium. Plantlets transferred to soil developed into plants of normal appearance, which flowered and set fruits.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.468-471
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• 2002

The present study was undertaken to Investigate the effects of low temperature and salicylic acid (SA) on chilling tolerance In acclimated and nonacclimated cucumber seedlings. Acclimation significantly affected survival and shoot dry weights. Injuries of acclimated seedlings at the third leaf stage were on the average smaller by half than those of the nonacclimated ones. Chilling caused a large increase in free proline levels, regardless of acclimation status. Exogenous treatment with SA resulted in improvement in growth and survival of acclimated, chilled seedlings, indicating SA and acclimation have common effects. Cycloheximide treatment In the presence of SA restored acclimation-induced chilling tolerance. An elevated proline level was observed in cold-treated and SA- treated plants and the level was more pronounced in the light than in the dark at chilled temperature, indicating that endogenous proline may play a role in chilling tolerance.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.4-8
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• 2003

Cucumber mosaic virus (CMV) belongs to genus Cucumovirus. The Cucumovirus group contains three distinct members： CMV, Tomato aspermy virus (TAV), and Peanut stunt virus (PSV). The type member, CMV is the most widespread and most studied. CMV is isometric particles about 30 nm in diameter. The genome of CMV is divided into three RNAs. In addition, RNA extracted from virus particles contains a fourth RNA that is a subgenomic RNA generated from RNA3. RNA1 and RNA2 are each encapsidated in separate particles, whereas RNAs3 and 4 are coencapsidated in a third particle. Hence, inoculation by three particles, transmitted either mechanically or by the aphid vector, is required to infect plants.(중략)

• Korean Journal Plant Pathology
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• v.14 no.1
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• pp.83-91
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• 1998

Gladioli (Gladiolus hybridus) showing flower colour breaking leaf mosaics, notched leaf, and dwarfing or lack of visible symptoms were collected from gladioli growing areas in Taegu and Kyungpook province, Korea. The three viruses isolated from the naturally infected gladioli were identified as broad bean wilt virus (BBWV), cucumber mosaic virus (CMV), and tobacco rattle virus (TRV) by their host range, immunosorbent electron microscopy (ISEM), enzyme-linked immunosorbent assay (ELISA), direct tissue blotting immunoassay (DTBIA), and intracellural symptoms. By DTBIA and ISEM, TRV was detected in gladiolus showing notched leaf, while CMV was frequently detected in gladioli with dwarfing, color breaking and malformation of flowers. BBWV was also often detected in many symptomless gladiolus plants, but TRV was detected in notched-leaf of gladiolus. Electron microcopic examination of negatively stained preparations showed that BBWV and CMV are spherical particles of 28 nm and 30 nm in diameter, and TRV is rigid rod-shaped particles of 40∼200 nm in length. The rigid rodshaped virus particles reacted positively with TRV antiserum in ISEM and DTBIA, respectively.

• The Plant Pathology Journal
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• v.17 no.3
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• pp.169-173
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• 2001

Virus disease occurred up to 62% in average in the greenhouse production of table tomato Seokwang in Suwon, Korea. From symptomatic transition of the labeled tomatoes, two different symptoms, mosaic and bud necrosis, were developed independently. Cucumber mosaic virus necrosis strain (CMV-N) was isolated from table tomato showing bud necrosis symptoms. The isolate caused the bud necrosis on four tomato cultivars and locally infected Chenopodium spp. and Vicia faba by mechanical inculation. The 5th RNA segment, satellite RNA, was identified from CMV-N-infected plants by dsRNA analysis. Crystals of virus particles were observed in cytosols and vacuoles. The virus particles of CMV-N presented abundantly in xylem vessel.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.149.1-149
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• 2003

A lily strain of Cucumber mosaic virus (LK-CMV) was not able to systemically infect zucchini squash (Cucurbita pepo), while Fny strain of CMV (Fny-CMV) caused systemic mosaic and stunting symptom at 4 days post-inoculation on the same host species. The pathogenicity of LK-CMV in zucchini squash was investigated by reassortments of genomic RNAs of LK-CMV and Fny-CMV for infection, as well as by pseudorecombinants generated from biologically active transcripts of CDNA clones of LK-CMV and Fny-CMV, respectively. The assessments of pathogenicity for LK-CMV indicated that RNA2 of LK-CMV was responsible for systemic infection in zucchini squash. In the protoplast of zucchini squash, the RNA accumulations of all constructed pseudorecombinants were indistinguishable and LK-CMV replication was slightly lower than that of Fny-CMV, suggesting that the inability of LK-CMV to infect squash plants was responsible for the poor efficiency of virus movement, rather than the reduction of replication function.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.355-360
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• 1996

In vitro-tested ribozyme against synthesized cucumber mosaic virus (CMV) RNA (Agric. Chem. & Biotech. 37:56-63(1994)) was expressed in tobacco plant to develop virus resistant plants. The ribozyme sequence was linked to cauliflower mosaic virus 35S promoter and nopaline synthase(nos) terminator and this chimeric 35S-ribozyme-nos gene was sequenced. The sequenced chimeric gene was transferred to Agrobacterium tumefaciens LBA4404 using tri-parental mating system. The E. coli HB101 containing chimeric gene was incubated with E. coli HB101(pRK2073) as a helper and Agrobacterium tumefaciens LBA4404. Then Agrobacterium cells containing the ribozyme construct was cocultivated with tobacco leaf pieces. Ten different plants were regenerated from kanamycin containing MS medium. The presence of the ribozyme construct in the transgenic tobacco plants was confirmed by polymerase chain reaction (PCR). Seven different transgenic plants in ten different kanamycin resistant plants showed the expected size (570 base pairs) of 35S-ribozyme-nos gene fragment. Total RNAs were isolated from four different transgenic plants and separated on a 1% agarose gel containing formamide. Northern hybridization with 35S-ribozyme-nos gene fragment as a probe indicated that ribozyme transcripts may be degraded tv nuclease. Therefore, nuclease-resistant ribozymes are needed for the development of virus-resistant transgenic plants using ribozymes.

• Journal of Bio-Environment Control
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• v.16 no.2
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• pp.101-107
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• 2007

This experiment was carried out to develop the substrate mixtures for the production of high quality plug seedlings of cucumber. Peatmoss based substrates, rice hull, carbonized rice hull, decomposed sawdust, perlite and granular rockwool were mixed by five different mixing ratioes (M1, M2, M3, M4 and M5). The cultivars used were cucumber (Cucumis sativus L. cv. Janghyung heukjinju) plants. The higher the content of peatmoss added, the higher the plant growth in terms of plant height, leaf area and total dry weight, which leading to the production of high quality plug seedlings. Seedlings growth of cucumber were greater in M5 mixtures [peatmoss:rice hull:decomposed sawdust=40:40:20(v/v)], M4 mixtures [peatmoss:rice hull:decomposed sawdust:granular rockwool=30:25:20:25(v/v)] and M2 mixtures [peatmoss:rice hull:decomposed sawdust:granular rockwool=20:20:15:25:20(v/v)] The concentrations of nutrient solution (EC) had a great influence on plant height, leaf area, total fresh and dry weight of cucumber seedlings growth. As the concentration of nutrient solution increased from 0.1 to $1.5dS{\cdot}m^{-1}$, the growth and seedling quality of cucumber in plant height, leaf area and dry weight were significantly improved.