• Journal of Ecology and Environment
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• v.38 no.3
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• pp.335-342
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• 2015

This research was conducted to examine the changes in growth and production of Oryza sativa L. cv. Ilmi, which was developed to cultivate high yielding rice variety in the Southern plains of Korea. The seedlings of the rice were cultivated from May to October in 2012 under three different conditions: control, AC-AT, ambient $CO_2$ + ambient temperature; AC-ET, ambient $CO_2$ + elevated temperature; EC-ET, elevated $CO_2$ + elevated temperature. The aboveground biomass, belowground biomass, the total biomass of the rice, and panicle weight per individual were the heaviest in the EC-ET. But, the number of grains per panicle and the weight of one grain was higher at the condition of AC-ET and EC-ET than that of AC-AT. The number of tiller was higher at the condition of AC-AT and AC-ET than that of EC-ET. However, there was no significant difference in the number of panicles per individual and the ripened grain rate among the control and global warming treatments. Crop yield was the highest in the EC-ET. This result means that the global warming condition should be considered in the selection of suitable paddy field for the limibyeo in the future.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.5-5
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• 2017

Too little and too much water due to climatic events is a significant cause of global food insecurity. Crops are less productive under water-limited conditions and all major crops, with the exception of rice (Oryza sativa), die within a few days of complete submergence. To complement our studies on genes such as SUB1A, (an ERF-VII transcription factor that provides robust submergence tolerance) and AG1 (a TREHALOSE 6-P PHOSPHATASE that promotes establishment of young seedlings underwater), we have retooled INTACT (${\underline{I}}solation$ of ${\underline{N}}uclei$ ${\underline{TA}}gged$ in specific ${\underline{C}}ell$ ${\underline{T}}ypes$) and TRAP (${\underline{T}}ranslating$ ${\underline{R}}ibosome$ ${\underline{A}}ffinity$ ${\underline{P}}urification$) for rice. These technologies enable us to follow dynamics in chromatin, nuclear pre-mRNAs and ribosome-bound mRNAs in meristems and diverse cell types. With these technologies we can better interpret responses to stresses and reestablishment of homeostasis. These include stress acclimation strategies involving changes in metabolism and development, such as dynamics in suberin deposition in sub-epidermal layers of roots that limit water loss under drought and oxygen escape during waterlogging. Our new data uncover dynamic and reversible regulation at multiple levels of gene regulation and provide new insights into processes of stress resilience. Supported by US NSF-PGRP Plasticity (IOS-1238243), Secretome (IOS-1546879) and REU (DBI-146129) grants.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.261-261
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• 2017

This study was carried out to provide basic data for spreading rice direct seeding by inducing stabilization of seedlings, yield and quality according to sowing times in rice direct seeding cultivation. In 2016, 'Sukwang' was seeded 3 times by 10 days interval on May. 10, 20, 30 and 6kg/10ha of seeding rate respectively in Iksan. In summary, the number of rice seedling establishment was higher than the optimum seedling establishment level at all sowing periods and the seeding rate was better as the sowing period was delayed. Weed development by sowing was the highest at early sowing, May 10, and decreased at late sowing. Heading dates were delayed by 3days for sowing on May 10, 7days for sowing on May 20, and 11 days on sowing on May 30. Rice yield increased with the delay sowing time and compared to the transplanting. It was 84% in sowing on May 10, 94% in sowing on May 20, and 99% in sowing on May 30. In addition, head rice ratio and head rice yield increased according to delayed of seedling.

• The Plant Pathology Journal
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• v.19 no.3
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• pp.138-142
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• 2003

Soil amendments with oriental herbal medicines such as fruit of Anethum graveolens, flower buds of Syzygium aromaticum, rhizome of Cnidium officinale, rhizome of Coptis chinensis, root bark of Paeonia suffructicosa, stem bark of phellodendron amurense, and stem bark of Cinnamomum cassia at the rate of 0.2％ (weight by volume of soil) significantly reduced Meloidogyne incognita infection (root gall formation) of tomato seedlings compared with the control. The most effective treatments were root bark of p. suffructicosa and stem bark of C. cassia as they gave minimum numbers of galls on tomato roots (4.7% and 8.9%, respectively, relative to control) as compared to other treatments. Another study with root bark of p. suffructicosa and C. cassia at different application doses also showed consistent results in reducing gall number. The control efficacy decreased as the application doses were lower-ed, indicating their dose-dependent control activities. These treatments significantly enhanced aboveground plant growths (total masses).

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.3
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• pp.67-74
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• 2012

This study was carried out to cultivate evergreen-leaved tree container seedlings having low cost of equipment and easy to control. Two species of V. odoratissimum var. awabuki and Q. glauca planting in respective underground container were showed survival rate above 90%. The Relative growth rates of height was good in non-treatment and root collar diameter was no significant difference between treatments. The T/R ratio was respectively 1.1, 1.0 in container type of F, G. and root's biomass products was more effective than others. A container type of F showed better Quailty index than others with 16.2 values. Q. glauca was higher T/R ratio in root development than shoot and the quality index was high in container type of E, D with 4.0. 3.5, respectively. On the basis of the results obtained in this study, we can concluded that the underground container type was suitable to F in V. odoratissimum var. awabuki and to D or E in Q. glauca.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.245-252
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• 2005

The objective of the present work was to determine the corresponding uptake and assimilation of ${NO_3}^-$ in roots and shoots of leafy radish by applying of mixed amino acids (MAA). The amino acids used in this experiment were alanine (Ala), ${\beta}-alanine\;({\beta}-Ala)$, aspartic acid (Asp), asparagines (Asn), glutamic acid (Glu), glutamine (Gln), and glycine (Gly). Leafy radish was grown by conventional fertilization with macro- and micronutrients under controlled conditions. The 15-day-old seedlings were treated 0, 0.3 and 3.0 mM of MAA containing 5 mM ${NO_3}^-$ in growth medium. Nitrate uptake was determined by following ${NO_3}^-$ depletion from the uptake solution. The activity of the enzymes related to the process of ${NO_3}^-$ reduction (NR: nitrate reductase; NiR: nitrite reductase; GS: glutamine synthetase) and the content of ${NO_2}^-\;and\;{ND_3}^-$ were analyzed in shoots and roots. The results of this study showed that ${NO_3}^-$ uptake was inhibited 38% with treatment of 0.3 mM of MAA. However, there was more than three times increase of N03- uptake in 3.0 mM MAA. In addition, the enzymatic activities were positively affected by the high MAA rate. Finally, the ${NO_3}^-$ content was increased slightly both in shoots and roots of leafy radish by MAA treatments.

• Korean Journal of Plant Resources
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• v.19 no.3
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• pp.405-410
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• 2006

A series of aqueous or methanol extracts from four different Korean salad plants were assayed to determine their allelopathy and antioxidant activity. The extracts applied on filter paper in a Petri-dish bioassay significantly inhibited root growth of against alfalfa (Medicago sativa) seedlings. Leaf extracts from 40 g dry tissue $L^{-1}$ of Aster yomena was most phytotoxic to alfalfa root growth, and followed by that of Cirsium japonicum, Taraxacum officinale, and Ixeris dentate. Methanol extracts of plants dose-dependently increased DPPH free radical scavenging activity in vitro. Antioxidant activity of methanol extracts from the same plant species was investigated, and the result showed high DPPH free radical scavenging activity in Cirsium japonicum, Aster yomena, and Ixeris dentate, however, in Taraxacum officinale was least activity. By means of HPLC analysis, chlorogenic acid, p-coumaric acid, and total phenolics with 7.68, 17.47 and 18.64 mg, $100g^{-1}$, respectively, showed the highest amounts in methanol extracts from Cirsium japonicum leaves. These results suggest that Compositae salad plants contain water-soluble substances with allelopathic potential as well as antioxidant activity.

• Plant Resources
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• v.8 no.2
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• pp.81-86
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• 2005

An efficient plant regeneration system of Gentiana scabra through somatic embryogenesis was established. Leaves and roots of seedlings of Gentiana scabra excised after germination were cultured on MS basal medium with 2,4-D, NAA or BA. Embryogenic callus was obtained on MS medium with 0.5 mg/L 2,4-D alone or 0.1 mg/L 2,4-D combimation with 1.0 mg/L BA after 45 days of culture. These embryogenic calli gave rise to somatic embryos, which subsequently developed into plantlets on MS medium without PGRs. Also, shoots were effectively differentiated from embryogenic callus when root segments were cultured on MS medium supplement with 0.1 mg/L 2,4-D and 1.0 mg/L BA. Shoots were effectively rooted on MS medium without PGRs. In vitro flowers were formed from plantlets cultured on MS medium with $5\%$ sucrose after 60 days of culture.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.441-445
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• 1987

The subcellular distribution of lipoxygenase in germinating soybean seeds (Glycine max[L.] AmSoy) was investigated by using differential centrifugation and sucrose density gradient fractionation. Most of lipoxygenase -1 and -2/3 activities was present in the supernatant fraction after differential centrifugation of homogenates prepared from three-day-old seedlings; only 1.5% of lipoxygenase activity remained in particulate fractions. The results of a sucrose density gradient fractionation (three-day-old) showed that the lipoxygenase activity coincided with acid phosphatase at the densities of 1.19, 1.23, $1.25g/cm^3$, even though most of lipoxygenase and acid phosphatase activities appeared in supernatant fractions. There was no indication that mitochondria contained any lipoxygenase activity, and it does not appear that glyoxysomes and ER contained any lipoxygenase activity either.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.3
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• pp.107-112
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• 2008

"Jeung-Bo-San-Lim-Gyeong-Je" (meaning "Revised Forest Management") has been well recognized as the informative document that introduces scientific knowledge and experiences of Korean ancestors regarding weather and climate. The tradition of Gwan-Cheon-Mang-Gi(i.e., empirical forecasting of short-term weather phenomena based on the status of cloud or sky) has been continuously utilized as a civilian weather forecasting method and even for very short-term weather prediction by operational forecasters these days. This agricultural technology textbook, published during the Great King Youngjo in Chosun-Dynasty, may be regarded as a poorly written document from the modern standpoint. Nonetheless, this study demonstrates that by and large the empirical knowledge contained in the book is indeed science based although their applications are limited to several hours for local forecasts in agricultural practices and daily living. For example, the wisdom of keeping water at an optimum level in a paddy field after sowing to prevent young seedlings from late frost damages was not at all different from the present technique of vinyl covered seedling nursery.