• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.207-215
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• 2023

This study was compared the soil environment and growth and yield of onion (Allium cepa L.) treated with non-mulching (NM) and mulching polyethylene film (PEF) and two biodegradable films (BFI and BFII) commonly used in farmhouses. Visual observation confirmed the degradation of BFI and BFII films after 150 days after tansplanting (DAT). BFII increased light penetration into the films and reduced the weight maintenace after 180 DAT, with a high decompostion at 30 days after soil tilling. Soil moisture contents much fluctuated between -14 kP and - 0 kPa in NM plots, increasing the minimum soil temperature of BFI plots. Mulching treatments decreased soil organic matter contents but did not subtantially increase soil mineral nutrients, soil bulk density, and number of bacteria compared to those of NM plots. Onion root growth was increased by PEF and BFI treatments at an early growth stage, 60 DAT, with the most remarkable stem extension observed for PEF and BFI treatments after 150 DAT. PEF and BFI treatments increased the bulb's diameter, length, weight, and lodging at 180 DAT. BFI treatments exhibited a high portion of the "very large" category producing with 55.3 tons ha^-1 based on the classification into bulb size, followed by PE (49.3 tons), NM (9.4 tons), and BFII treatments (2.7 tons) at 230 DAT.

• Clinical and Experimental Reproductive Medicine
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• v.33 no.3
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• pp.171-178
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• 2006

Objective: Human embryonic stem (ES) cells have a great potential in regenerative medicine and tissue engineering. The human ES cells could be differentiated into specific cell types by treatments of growth factors and alterations of gene expressions. However, the efficacy of guided differentiation and isolation of specific cells are still low. In this study, we characterized isolated cells from differentiated human ES cells by magnetic activated cell sorting (MACS) system using specific antibodies to cell surface markers. Methods: The undifferentiated hES cells (Miz-hESC4) were sub-cultured by mechanical isolation of colonies and embryoid bodies were spontaneously differentiated with DMEM containing 10% FBS for 2 weeks. The differentiated cells were isolated to positive and negative cells with MACS system using CD34, human epithelial antigen (HEA) and human fibroblast (HFB) antibodies, respectively. Observation of morphological changes and analysis of marker genes expression were performed during further culture of MACS isolated cells for 4 weeks. Results: Morphology of the CD34 positive cells was firstly round, and then it was changed to small polygonal shape after further culture. The HEA positive cells showed large polygonal, and the HFB positive spindle shape. In RT-PCR analysis of marker genes, the CD34 and HFB positive cells expressed endodermal and mesodermal genes, and HEA positive cells expressed ectodermal genes such as NESTIN and NF68KD. The marker genes expression pattern of CD34 positive cells changed during the extension of culture time. Conclusion: Our results showed the possibility of successful isolation of specific cells by MACS system from undirected differentiated human ES cells. Thus, MACS system and marker antibodies for specific cell types might be useful for guided differentiation and isolation of specific cells from human ES cells.

• Korean Journal of Medicinal Crop Science
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• v.2 no.1
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• pp.7-13
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• 1994

This study was conducted to investigate the relationships between yearly variations of climatic factors and yearly variations of productivity in Alisma plantago L. In addition, correlation coefficients among yield and yield components were estimated. The data of yield and yield components were collected from the Statistical Year Book of Seungju province, Reserach Report of Seungju Extension Station of Rural Development Administration, and farmers for 10 years from 1983 to 1992. The meteorological data gathered at the Seungju Weather Station for the same period were used to find out the relationships between climatic factors and productivity. Yearly variation of the amount of precipitation in October and the minimum temperature in November were large with coefficients of variation(C.V.) of 106.44, 144.08%, respectively, but the variation of the average temperature, maximum temperature, minimum temperature from July to September were relatively small. Fresh weight and dry weight of roots vary greatly with C. V. of 30.62, 31.85%, respectivly. Plant height and stem length show more or less small C. V. of 5.51, 6. 26%, respectively and leaf width, leaf length, number of stems and root diameter show still less variation. Correlation coefficients between maximum temperature in November and plant height, stem diamter, number of stems, root diamter and dry weight of roots are positively significant at the 5% level. There are high signficant positive correlations observed, between yield and yield components. The maximum temperature would be used as a predictive variable for the estimation of dry weight of roots and number of stems. Simple linear regression equations by the least square method are estimated for number of stems $(Y_1)$ and the maximum temperature in November(X) as $Y_1=4.7114+0.5333\;X\;(R^2=0.4410)$, and for dry weight of roots$(Y_2)$ and the maximum temperature in November(X) as $Y_2=55.0405+14.3233\;X\;(R^2=0.4511)$

• Korean Journal of Weed Science
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• v.32 no.2
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• pp.98-106
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• 2012

This research has been carried out to find out the highest effect on insecticidal, fungicidal and herbicidal activities in leaves, stem and tuber extracts of yacon (Smallanthus sonchifolius) and extraction methods such as water, boiling water and methanol. Characteristics of potential herbicidal components among extraction methods were investigated by solvent fractions such as hexane, chloroform, ethyl acetate, butanol, and water. Generally, methanol extract was the best on inhibition of germination rate, plant height, and root length in cucumber and barley. On the other hand, the inhibition effect on growth in cucumber and barley was the best in tuber among plant parts of yacon. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fraction, but there were no differences in other fractions. Digitaria sanguinalis L. and Solanum nigrum L. by 5 and 10% extractions of yacon tuber were controlled by more than 70~80% and 95~100%, respectively. However, there was no inhibition effect on foliar treatment in cucumber and barley as affected by 5 and 10% extractions of yacon tuber. Mortality of green peach aphid (Myzus persicae Sulzer) was 50% at 3 days after treatment of 5% extracts of yacon leaves. Mortality of brown plant hopper (Nilaparvata lugens Stal) was only 24% in 5% extracts of stems and leaves with midrib, but was 57% in 5% extracts of leaves without midrib. There was no fungicidal effect on anthracnose (Colletotrichum truncatum), wilt disease (Fusarium oxysporum), verticillium wilt (Verticillium dahliae), bacterial blight (Xanthomonus oryzae) in 5% extracts of yacon leaves.

• Weed & Turfgrass Science
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• v.2 no.3
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• pp.242-247
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• 2013

Currently, methods for controlling weeds in organically produced crops have not been as effective as conventional methods. This research was carried out to determine the herbicidal effects of leaf, stem, fruit, root extracts of Trichosanthes kirilowii. The extraction methods used were water, boiling water and ethanol. The characteristics of potential herbicidal components among extraction methods were investigated by using the following solvent fractions: hexane, chloroform, ethyl acetate, butanol, and water. Generally, water extracts provided the best on inhibition of germination rate, plant height, and root length in cucumber and barley. Specifically, extractions made from fruit parts of T. kirilowii provided the greatest inhibition effect on plant growth in cucumber and barely. Inhibition of germination rate, plant height, and root length in cucumber and barley in solvent fractions was the best in water fractions, but there were no significant differences among the other fractions. Digitaria siliaris and Solanum nigrum were controlled 80-100% by 5% extractions of water fraction. However, there were no herbicidal effects from foliar treatment in cucumber, barley, black nightshade, and henry crabgrass by 5% extractions of the water fraction. These results show that extractions of T. kirilowii can be used for controlling some weeds in organically produced crops.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.630-634
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• 2009

"Hyedang", a new covered cultivar derived from the crosses between "Suwon300" and "Haganemugi//CI08397/Haganemugi" developed at the Honam Agricultural Research Institute (HARI), NICS, RDA in 2007. The origin of "Hyedang" is "Iksan 407" (SB951033-B-B-B-72). The initial cross was made in 1995 and the selected line showed a high yield and good quality characteristics under yield trial test in 2004. "Iksan407" consistently performed well for three years (2005-2007) from the four locations of regional yield trial (RYT) in Korea and released as "Hyedang". The characteristics of "Hyedang" were the following: rate III growth habit, green leaf and stem, compact spike and with long rough awns. The heading date was April 25 in upland and April 17 in paddy field, which was 2 and 3 days earlier than that of check cultivar, "Olbori". The culm length was 80 cm which was 8 cm shorter than those of check cultivar. It showed spike length of 4.3 cm and 696 spikes per $m^2$, 51 grains per spike, 35.0 g of 1,000 grain weight and 704 g of test weight. It showed stronger winter hardiness and higher resistance to barley yellow mosaic virus (BaYMV) than those with check cultivar. It showed similar protein content and higher whiteness than those of the check cultivar and diastatic power was higher than that of Olbori. The average yield of the pearled grain in the RYT was $4.17ton\;ha^{-1}$ in upland and $4.27ton\;ha^{-1}$ in paddy field, which was 23% and 9% higher than that of the check cultivar, respectively. This cultivar would be suitable for the area above the daily minimum mean temperature of $-8^{\circ}C$ in January in Korean peninsula.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.649-656
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• 2012

To obtain the basic information for agricultural utilization of germanium (Ge), the growth characteristics and Ge absorption in rice plant were investigated under different Ge concentrations by foliar spray application. The Ge concentrations were treated with 0 (control), 10, 20, 40 and $80mg\;L^{-1}$ in pot (1 5000$^{-1}$ a), respectively. The Ge absorption rate in rice by foliar spray application with $80mg\;L^{-1}$ in pot was higher in the order of leaf (5.75%) > stem (4.52%) > root (<0.01%). By foliar spray application, the Ge content in rice was higher in the order of $80mg\;L^{-1}$ > $40mg\;L^{-1}$ > $20mg\;L^{-1}$ > $10mg\;L^{-1}$. When rice was treated with $80mg\;L^{-1}$ of Ge, the Ge content in rice grain was higher in the order of rice bran ($0.21mg\;pot^{-1}$) $\gg$ brown rice ($0.04mg\;pot^{-1}$) ${\geq}$ polished rice ($0.03mg\;pot^{-1}$). By foliar spray application, the Ge uptake in rice bran was higher than that in other parts. Therefore, optimum Ge concentration by foliar spray application was $80mg\;L^{-1}$ in pot based on the results from the Ge treatments.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.373-381
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• 2008

To select of optimum rice species and germanium (Ge) application method for production of functional rice with Ge, the growth characteristics, Ge absorption and grain quality of rice plant were investigated under different rice species (Hopyungbyeo, Junambyeo, Ilmeebyeo and Dongjinbyeo) and Ge application method (soil application and foliar spray). The rice yield by soil application was higher in the order of Hopyungbyeo $\fallingdotseq$ Junambyeo > Ilmeebyeo >> Dongjinbyeo. On the other hand, the rice yield by foliar spray was higher in the order of Junambyeo >> Ilmeebyeo > Dongjinbyeo > Hopyungbyeo. The rice yield by soil application was higher than that by foliar spray regardless of rice species. For soil application, the Ge absorption in various parts of the rice was higher in the other of rice bran > brown rice > polished rice regardless of rice species. The Ge absorption of brown rice in Hopyungbyeo, Ilmeebyeo, Dongjinbyeo and Junambyeo by soil application was 14.5, 8.0, 11.6 and $10.4\;mg\;kg^{-1}$, respectively. In leaf, stem and root, the Ge absorption by foliar spray was higher than that by soil application, whereas, in rice bran, brown rice and polished rice, the Ge absorption by soil application was higher than that by foliar spray. The optimum rice species and Ge application method were demonstrated to be Hopyungbyeo and soil application, respectively, which provided suitable conditions for production of functional rice with Ge.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.719-727
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• 2010

Reduced irradiance promotes shoot elongation depending on developmental stage and environmental factors and decreases plant quality in $Cyclamen$ $persicum$ Mill. To determine the petiole elongation responses to low irradiance, 'Metis Scarlet Red' cyclamen at different developmental stages [juvenile (5-6 unfolded leaves), transitional (1-3 visible flower buds), or mature (1-3 elongating peduncles)] was grown in growth modules at 60 (low light, LL) or 240 (high light, HL) ${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ PPFD within the growth chambers at different temperatures [16/12 (low temperature, LT), 22/18 (medium temperature, MT), or 28/$24^{\circ}C$ (high temperature, HT) (day/night)]. In Experiment I, juvenile plants were either kept in an LL or HL module during the entire treatment of 4 weeks or were transferred to the other module at 1, 2, or 3 weeks after treatment in an MT chamber. In Experiment II, juvenile, transitional, or mature plants were moved to the HL module at 0, 3, 6, 9, or 12 days after being placed in the LL module at the MT chamber and grown for 21 days. In Experiment III, transitional plants were moved to the HL module at 0, 3, 6, 9, or 12 days after being placed in the LL module at the LT, MT, or HT chambers. As the exposure duration to LL increased from 0 to 4 weeks or from 0 to 12 days, petiole length and plant height increased at all temperatures and developmental stages. In Experiment I, the exposure to LL during the latter period, rather than the early period, increased elongation rate. In Experiment II, petiole elongation in transitional plants was more sensitive to LL than juvenile or mature plants during the early period of the treatment for 12 days. In Experiment III, petiole length increased with increasing temperature and exposure duration to LL. Petiole elongation rate at HT increased rapidly from the beginning of LL exposure as compared to LT. Increase of $6^{\circ}C$ in temperature had the similar effect to LL exposure for 3 days in petiole elongation. To conclude, transitional cyclamen under higher temperatures responds more immediately to low irradiance and elongates its petioles.

• Food Science and Preservation
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• v.15 no.3
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• pp.421-426
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• 2008

In older to prepare functional food materials from Acanthopanax koreanum, changes of major constituents by extracting with water and ethanol were investigated Extracting 300 g of below 0.5 cm size dried sample in 7.5 L of water or $30{\sim}95%$ ethanol for 9 hr at $100^{\circ}C$ were carried out pH during extraction was between 4.0 and 6.5. Color b-value of extracts was increased according to lower ethanol concentration and longer extraction time. Color a-value and b-value was increased more in stem than in root Extracts were increased rapidly within $2{\sim}3\;hr$. The extract in $30{\sim}70%$ ethanol was $0.84{\sim}1.34%(w/v)$ with root Main free sugar of extracts was sucrose in root. The eleutherosides were extracted rapidly within 3 hr, moreover were increased in water or $30{\sim}70%$ ethanol more than 95% ethanol concentration. Extraction of acanthoic acid from root was more affected on ethanol concentration than extracted time, moreover it was detected only trace by extracting with water. Furthermore, acanthoic acid was extracted rapidly within 2 hr in $50{\sim}70%$ ethanol, and was extracted 3 times higher with 70% ethanol than with 30% ethanol. The content of acanthoic acid in residue after extraction was affected largely by extraction solvents. The extraction efficiency in 70, 50 and 35% of ethanol concentration was about 95, 90 and 35% respectively. The eleutherosides were extracted to 95% with water or nature of water and ethanol. Therefore, the reflux extraction in $40{\sim}70%$ ethanol concentration for $3{\sim}5\;hr$ was adequate for extraction of functional materials from Acanthopanax koreanum.