• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.249-254
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• 2016

This study was carried out to evaluate the efficiency of white shading agent for reduction of greenhouse air temperature and to develop cost-effective cooling strategies for strawberry seedling production during hot seasons. Experiment results showed that solar radiation ($W/m^2$) was reduced by 14~17% and 33~37% for 15% and 35% white wash shading treatments, respectively, in black shading net treatment solar radiation was reduced by 39~44% compared to non-shaded treatment. Measured greenhouse air temperatures in 15% and 35% white wash shading treatments were $38.4^{\circ}C$ and $36.5^{\circ}C$, respectively, whereas in black shading net covered greenhouses air temperature was $35.1^{\circ}C$, thereby 35% and 15% shading treatments showed 3.3 and $1.9^{\circ}C$ higher air temperatures than black net shading treatment. Crown diameter of strawberry plants in black net shading treatment was 7.5mm, and in 15% and 35% white wash shading treatments were 8.6mm and 8.3mm, respectively. Strawberry transplants grown in 35% white wash shading treatment produced the highest above ground fresh weight(7.8g), followed by 15% white wash shading(6.7g) and black net shading treatments(5.8g). Also, both 15% and 35% white wash shading treatments produced higher root fresh weight(4.1g and 4.3g) compare to black net shading treatments(2.7g).

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.245-256
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• 2015

In the agricultural industries, LEDs are used as supplementary, as well as main lighting sources in closed cultivation systems. In cultivation using artificial light sources, various light qualities have been tried to supplement fluorescent lamps to promote plant growth and metabolism. Microarray analysis of Brassica rapa seedlings under blue and fluorescent mixed with blue light conditions identified changes in three genes of the glucosinolate pathway. This attracted attention as functional materials highly expressed 3.6-4.6 fold under latter condition. We selected four more genes of the glucosinolate pathway from the Brassica database and tested their expression changes under fluorescent light mixed with red, green, and blue, respectively. Some genes increased expression under red and blue mixed conditions. The Bra026058, Bra015379, and Bra021429; the orthologous genes of CYP79F1, ST5a, and FMOGS-OX1 in Arabidopsis, are highly expressed in Brassica rapa under fluorescent mixed with blue light conditions. Further, Bra029355, Bra034180, Bra024634, and Bra022448; the orthologous genes of MAM1, AOP3, UGT74B1, and BCAT4 in Arabidopsis, are highly expressed in Brassica rapa under fluorescent mixed with red light conditions. The various light conditions had unique effects on the varieties of Brassica, resulting in differences in glucosinolate synthesis. However, in some varieties, glucosinolate synthesis increased under mixed blue light conditions. These results will help to construct artificial light facilities, which increase functional crops production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.449-457
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• 1993

Three naked and three malting barley cultivars were grown at constant temperatures of 4, 8, 12, 16, 20, 24 and 28$^{\circ}C$, and day/night temperatures of 6/2, 10/6, 14/10, 18/14, 22/18, 26/22 and 30/26$^{\circ}C$ through the fourth leaf stage in growth chambers to determine the effects of the temperature on leaf emergence rate and phyllochron in naked and malting barley seedlings. The number of leaves per main stem was recorded daily from the first leaf stage to the fourth. At a given temperature, the emergence of new leaves was a linear function of time for all cultivars. There were no great differences in leaf emergence rate and phyllochron between constant and variable day/night temperature regimes except at 28$^{\circ}C$. Leaf emergence rate and phyllochron significantly differed among cultivars and among mean temperatures within cultivars. For all cultivars, leaf emergence rate per day increased parabolically with increasing mean air temperature until an optimum temperature was reached and then declined. There were no differences in the optimum temperatures for the leaf emergence rate per day among six cultivars, which ranged 20.1 to 21.5$^{\circ}C$. The leaf emergence rates at the optimum temperatures ranged 0.202 to 0.226 leaves / day for naked barley cultivars and 0.231 to 0.241 leaves / day for malting barley cultivars. As temperature increased, leaf emergence rate per GDD decreased exponentially and the phyllochron (GDD/leaf) increased exponentially. The mean of the phyllochron for six cultivars was 46.2 GDD at 4$^{\circ}C$ and 129.3 GDD at 28$^{\circ}C$. These results suggest that the temperature and cultivar effects must be considered for prediction of leaf development in barley.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.239-247
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• 2018

Soybean produces three major types of isoflavones, daidzein, genistein, and glycitein aglycones and their glucosides and malonylglucosides. It has been known that malonylated glucosides are rapidly converted to their corresponding aglycones due to the unstable thermolabile glucoside malonates; therefore, the analytical study of malonylated glucosides has been insufficient. In this study, we analyzed the malonylglucoside content in soybean seeds. Isoflavone analysis of three soybean cultivars revealed that 81.5~90.0% of the total isoflavones were malonylglucosides, whereas aglycones were rarely detected. Moreover, the total isoflavone content increased during a 5-day germination period where growth regulators and coumaric acid treatments tended to yield higher isoflavone content than the normal germination treatment, however the differences were not significant; notably, the isoflavone accumulation trend continued with additional germination days. The content of malonylglucoside was higher than that of other isoflavones, which was 83.7~86.6% of the total isoflavone content in seeds with a 3-day germination period. Furthermore, isoflavones were significantly accumulated in the hypocotyl of seedlings with a 5-day germination period. The content of isoflavone in the hypocotyl of the Pungsannamul-kong was 10,240 ug/g when treated with coumaric acid, which was considerably higher than that of other cultivars and treatments. Additionally, soybean seeds heated at $60^{\circ}C$ for 1 hour produced higher isoflavone content than non-heated soybean seeds. Our results show that it is possible to increase the isoflavone content in soybean seeds through various treatments.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.194-194
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• 2017

Camelina (Camelina sativa L.) is a potential bio-energy crop that has short life cycle about 90 days and contains high amount of unsaturated fatty acid which is adequate to bio-diesel production. Enhancing environmental stress tolerance is a main issue to increase not only crop productivity but also big mass production. CsRCI2s (Rare Cold Inducible 2) are cold and salt stress related protein that localized at plasma membrane (PM) and assume to be membrane potential regulation factor. These proteins can be divide into C-terminal tail (CsRCI2D/E/F/G) or no-tail group (CsRCI2A/B/C/H). However, function of CsRCI2s are less understood. In this study, physiological responses and functional characterization of CsRCI2s of Camelina under salt stress were analyzed. Full-length CsRCI2s (A/B/E/F) and CsPIP2;1 sequences were confirmed from Camelina genome browser. Physiological investigations were carried out using one- or four-week-old Camelina under NaCl stress with dose and time dependent manner. Transcriptional changes of CsRCI2A/B/E/F and CsPIP2;1 were determined using qRT-PCR in one-week-old Camelina seedlings treated with NaCl. Translational changes of CsRCI2E and CsPIP2;1 were confirmed with western-blot using the antibodies. Water transport activity and membrane potential measurement were observed by cRNA injected Xenopus laevis oocyte. As results, root growth rate and physiological parameters such as stomatal conductance, chlorophyll fluorescence, and electrolyte leakage showed significant inhibition in 100 and 150 mM NaCl. Transcriptional level of CsPIP2;1 did not changed but CsRCI2s were significantly increased by NaCl concentration, however, no-tail type CsRCI2A and CsRCI2B increased earlier than tail type CsRCI2E and CsRCI2F. Translational changes of CsPIP2;1 was constitutively maintained under NaCl stress. But, accumulation of CsRCI2E significantly increased by NaCl stress. CsPIP2;1 and CsRCI2A/B/E/F co-expressed Xenopus laevis oocyte showed decreased water transport activity as 61.84, 60.30, 62.91 and 76.51 % at CsRCI2A, CsRCI2B, CsRCI2E and CsRCI2F co-expression when compare with single expression of CsPIP2;1, respectively. Moreover, oocyte membrane potential was significantly hyperpolarized by co-expression of CsRCI2s. However, higher hyperpolarized level was observed in tail-type CsRCI2E and CsRCI2F than others, especially, CsRCI2E showed highest level. It means transport of $Na^+$ ion into cell is negatively regulated by expression of CsRCI2s, and, function of C-terminal tail is might be related with $Na^+$ ion influx. In conclusion, accumulation of NaCl-induced CsRCI2 proteins are related with $Na^+$ ion exclusion and prevent water loss by CsPIP2;1 under NaCl stress.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.390-396
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• 2015

This study was carried out in order to closely examine quality index by shading level of 2-year-old (1-1 seedling) container seedling of Daphniphyllum macropodum which is known as the species of having shade tolerance that is evergreen broad leaved tree in the warm temperate region. The shading treatment was regulated with the shading level of full sunlight, and 35%, 55%, 75%, 95% of full sunlight. As a result of surveying growth according to the shading level, both height and root collar diameter were surveyed to be the highest with 45.1 cm and 8.22 mm, respectively, under 75% of shading. The next was surveyed to be 43.2 cm & 8.05 mm and 42.5 cm & 7.98 mm, respectively, in order of 35% and 55% in shading. Leaf, shoot, root, and whole dry mass production were the highest under 75% of shading. The next was higher in leaf, stem, and whole dry mass production under 55% of shading. A root was higher under 35% of shading in the next. H/D ratio was the range of 5.29~5.35 under the 35~75% shading that showed the relatively high height and root collar diameter. T/R ratio was the lowest with 1.17 under 35% of shading. It was 0.41 under 95% of shading as for LWR, 0.24 under 75%-95% of shading as for SWR, and 0.46 under full sun and 35% shading as for RWR. QI was the highest with 3.74 under 75% of shading. As a result of surveying the whole experiment, it is concluded that the production of D. macropodum seedling is more effective under 75% shading

• Journal of Korean Society of Forest Science
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• v.17 no.1
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• pp.1-15
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• 1973

In an effort to improve the major tree species in Korea, the seed of Robinia pseudoacacia, Pinus rigida, Pinus densiflora, Pinus thunbergii and Larix leptolepis were treated with X-ray and thermal neutron at the Brookhaven National Laboratory, and germination rate of the seed and some characteristics of the seedlings from irradiated seed were investigated and the results were summarized as follows. 1. The germination rate of the irradiated seed of Robinia pseudoacacia, Pinus densiflora, Pinus thunbergii and Pinus rigida was decreased, when the irradiation time of thermal neutron increased from 3 hours to 9 hours. The seed of Larix leptolepis was completely died out in all range of irradiation time. 2. The seed of Pinus densiflora, Robinia pseudoacacia and Pinus rigida showed low germination rate, when the dosage of radiation increased in the range of 10,000r-30,000r X-ray. This dosage of radiation was almost lethal to the seed of Pinus thunbergii and Larix leptolepis. 3. The growth rate of radiated Robinia pseudoacacia has been decreased when the dosage of X-ray and thermal neutron increased. However, the trees treated with thermal neutron for 3 hours showed 14.9 percent-increase in seedling height and some thornless individuals appeared in this treatment. 4. Individuals with variegated leaf, rugose leaf and albino were appeared in X-ray and thermal neutron treatment. 5. Abnormal mitosis of somatic cell, cell with two nucleoli, cell with two nuclei and chromosome clump in mitosis of somatic cell were observed in Robinia pseudoacacia irradiated with thermal neutron. 6. Resistanty against pawdery mildew was decreased in Robinia pseudoacacia radiated with X-ray and thermal neutron. 7. Length of stomata did not show any difference however number of stomata per unit area decreased in Robinia pseudoacacia radiated with thermal neutron. The leaves of Robinia pseudoacacia radiated with thermal neutron were thicker than those of non-treated one, but width of palisade tissue was decreased. The most sensitive one among those species to the thermal neutron treatment was Larix leptolepis, followed by Pinus densiflora, Robinia pseudoacacia, Pinus thunbergii and Pinus rigida in the order. In X-ray treatment, the most sensitive one was Larix leptolepis, followed by Pinus densiflora, Pinus thunbergii, Pinus rigida and Robinia pseudoacacia in the order. Morphological, cytological variation of the radiated Robinia pseudoacacia seemed to indicate some possibility to be used for tree improvement.

• Journal of Korean Society of Forest Science
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• v.87 no.2
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• pp.308-315
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• 1998

This study was conducted to evaluate the availability of the forest topsoil as a source of the "Native-soil(seed-fertilizer-soil materials)" for the hydroseeding measures which are environmentally and ecologically stable revegetation measures on rock cut-slopes. Soil sampling and factorial experiments were used with a split plot design(main plot : forest soil type and soil spraying thickness, subplot : seeding rate) in 1996. Results obtained in this study were summarized as follows : Because of the competition between the seeded(introduced) species and the native species, the number of naturally emerged species in the non-seeded plot and that of in the seeded plot were $5{\sim}9species/0.07m^2$ and $2{\sim}6species/0.07m^2$, respectively. As increasing the seeding rate(introduced species), the appearance ratio of naturally emerged species was decreased. The total number of individuals was high in the plot which used coniferous forest soil as a seed source, however the ratio of the individuals of naturally emerged species was high(30%) in the plot which used deciduous forest soil. The usage of the forest topsoil as seed bank source onto the "Native-soil" materials for hydroseeding could be reduce the seeding rate to $1,000seedlings/m^2$. According to the several factors which are competition between seeded species and naturally emerged species, dryness of soil materials, and seed burial, spraying thickness with more than 5cm was suitable for the growth of plants in variety.

• Journal of Korean Society of Forest Science
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• v.82 no.4
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• pp.366-380
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• 1993

Quercus acutissima ectomycorrhizae were classified as apical type, linear type, clavate type, diffuse type, pyramidal type, coralloid type, and nodular type. The surface texture of the fungal mantle at the initial stage of mycorrhizal formation was velvety. The surface texture of Pisolithus tinctorius(Pt) mycorrhizae at 30 September was well-developed felty mantle, Yellowish white. Except Pt all mycorrhizae formed by ectomycorrhizal fungi used to experiment were white with felty mantle. Mycorrhizae at the initial stage of mycorrhizae formation were creamy or creamy brown and swelled with thin mantle. Transverse and longitudinal sections showed radially-elongated cortical cell layers and epidermal cell with Hartig net. The transversal wideth of radially-elongated cortical and epidermal cells in the mycorrhizae with thick mantle on 30 September did not different with the mycorrhizae with thin mantle on the initial stage. Pt #250 formed coralloid mycorrizae but Pt KJ-1 did not although they are same species. On the mean length of linear type ectomycorrhizae of Pt KJ-1(2.21mm) was 1.5 times longer than that of Pt #250(1.32mm). The total dry weight of seedlings inoculated with Pt KJ-1, Pt #250, Lycoperdon pedicellatum, Scleroderma verrucosum were significantly heavier than those of suillus granulatus, Laccaria laccata.

• Korean Journal of Organic Agriculture
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• v.18 no.1
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• pp.93-104
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• 2010

This study was conducted screening of the population densities of fungal pathogens and insect and observed the disease symptoms on the organic sweet corn seed producing field from 2008 to 2009. The dissemination spores, Alternaria sp., Cladosporium sp., Helminthosporium sp., Pyricularia sp., Collectotrichum sp., and Bipolaris sp., were detected and the three fungal spores from the front were observed for whole growth stage. Seed and seedling diseases were shown as the rotted seed and damping-off seedling caused by Penicillium sp. and Rhizoctonia sp.. The larva of Black cutworm cut down the root crown of seedlings. The damaged plants were ranged from 14% to 16%. On the Oriental corn borer, the population densities and the percentage of damaged plants were showed a low difference between two sweet corn varieties. The population densities of Oriental corn borer were scored as from 3.5 to 20.5 in 2008 and from 0.5 to 6 in 2009. Also the percentage of damaged plants were significantly increased until harvesting stage and was recorded from 7.5% to 21% in 2008 and from 1% to 46% in 2009. On the Corn leaf blight, the percentage of diseased plant were scored from 7% to 34% in 2008. The first occurrence of date was after June 18, and the percentage of diseased plant was continuously increased after August 21 and the values of diseased plants was ranged from 56% to 69% in 2009. On common smut, the percentage of diseased plant was recorded from 5% to 15% in 2008, and the first occurrence date were delayed as 17 days (July 17) and were showed less than 8% of diseased plants in 2009. Corn Southern Leaf spot was scored as average 11% at early stage and showed high score as 62% at September 19 in 2008. In 2009, the first occurrence date were advanced about 20 days (after June 8), and continuously increased up to 86% in 2009.