• Journal of Plant Biology
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• v.20 no.2
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• pp.103-107
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• 1977

Two sample varieties of Yushin and Jinheung were used for the experiment in low-level wetty paddy field which was arranged with PVC pipe underdrainage of 6m in distance and 60cm, 90cm, and 120cm in depth and control, using sprit plot design with three replications. On the yield of brown rice, Yushin was increased by 24.8% in the 90cm plot and Jinheung by 16.7% in the 120cm plot, respectively, over the control. The ratio of matured grains of these two varieties was increased significantly by the underdrainage and the number of grains per head of Yushin was also increased in drained plots. Otherwise, the underdrainage enhanced the plant height in the early growth of rice plant and further increased the culm height and panicle length. It seemed that these results might enhance the light-receiving effciency in the latter growth of rice plant and bring about the effect fo increased yields by the underdrainage.

• Journal of Plant Biology
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• v.16 no.1_2
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• pp.23-29
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• 1973

The effect of phosphorus nutrition on the content of deoxyribonucleic acid(DNA), ribonucleic acid(RNA), crude protein and plant growth of soybean plant(Glycine max, Merr.) was studied. Yields of the above-and under-ground parts of the soybean plant in terms of dry weight, the amounts of crude protein, RNA and DNA continued to increase with increasing phosphorus supply. The amounts of RNA and crude protein were highest in the leaf tissues where most intensive growth was taking place. The relationships among DNA, RNA, crude protein and plant growth appeared to consist of the central dogma which has immortalized, while DNA in plant tissue was subject to charges cuased by external environmental facters such as phosphorus nutrition.

• Magazine of the Korean Society of Agricultural Engineers
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• v.35 no.2
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• pp.73-80
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• 1993

A simplified physiologically-based dynamic model, SIMRIW was selected for predicting the growth and yield of rice. The applicability of the model to the rice cultivars and weather conditions in the Republic of Korea was evaluated. Parameters of the model were calibrated using actual rice yields in Suweon region and an optimization scheme, Constrained Rosenbrock Algorithm. The simulated results from the calibrated model were in good agreement with the field data. The model with parameters calibrated for Suweon was applied to other five regions for the evaluation of transferability, but the simulated results fell short of satisfaction. However, the model is found to be applied to real-time prediction of the growth and yield of rice crop, which is believed to be useful for timely rice crop management, agricultural policy making, and optimal irrigation water management.

• Korean Journal of Organic Agriculture
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• v.14 no.1
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• pp.69-83
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• 2006

This experiment was conducted to investigate effects of application of diluted and undiluted cattle slurry with water on seasonal and annual dry matter yields and feed values of tall fescue in the uncultivated rice paddy and it was compared with chemical fertilizer. Annual dry matter yields for diluted (average 6.43 ton DM/ha) and undiluted (average 6.56 ton DM/ha) cattle slurry were significantly higher (p<0.05) than those of no fertilizer (3.82 ton DM/ha). This trend was much more conspicuous in treatments applied in spring. In chemical fertilizer treatments, fertilizers with P and K (6.12 ton DM/ha), and P, K and N (10.13 ton DM/ha) had significantly (p<0.05) higher dry matter yields compared with no fertilizer. However, annual dry matter yields for treatments of P and K mixture tended to be lower than those of cattle slurry applications. The efficiency of DM production for inorganic nitrogen in chemical fertilizers annually averaged 26.7kg DM/kg N. In terms of cutting frequencies, it was highest in 2nd growth followed by 1st and 3rd growth. On the other hand, efficiencies of annual DM production of nitrogen for diluted and undiluted cattle slurry were 18.3 and 17.4 kg DM/kg N, respectively, especially, highest in 2nd growth. While, efficiencies of DM production for cattle slurry versus for inorganic nitrogen were 68.5 (undiluted) and 65.2% (diluted), respectively. For annual crude protein contents of tall fescue, no fertilization (11.5%) was significantly higher than chemical fertilizer, but that was lower than cattle slurry ($12.4{\sim}12.6%$) diluted with water. on the contrary, no fertilizers had significantly lower NDF (64.1%) and ADF (37.2%) contents than those of any other treatments, but their RFV (87.0) was significantly higher (p<0.05) than other treatments. The application of cattle slurry and their dilution significantly increased yields of crude protein and total digestible nutrients compared with no and/or P and K fertilizers (p<0.05). This trend was more conspicuous in cattle slurry applied in the early spring.

• Journal of Sericultural and Entomological Science
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• v.18 no.1
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• pp.1-5
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• 1976

This work was carried out to investigate how the effects on the growth af branches and the yield of mulberry leaves are shown, when two of each dwarf and normal branches are thinned out in sumner or early autumn. The results obtained are summarized as follows. 1) In mulberry trees after spring pruning: in case of thin out branches in summer and harvest in autumn (42 days after treatment), (1) The average length of branches in thin out trees showed 19% increase by autumn, which turned out to be 11% higher than that of non-thin out did (8%) (2) The thin out treated mulberry trees presented 9% increase in total yields of summer and autumn, when compared with those of the non-thin out trees. 2) In mulberry trees after sumner pruning: in case of thin out branches in early autumn and harvest either in autumn (15 days after treatment) or in late autumn (28 days after treatment), (1) The average length of branches showed about 6∼7% and 8%, intercase by autumn and late autumn, respectively. Thus no effects of thin out treatment could be recognized in growing of branches. (2) The thin out treated mulberry trees presented about 6% increase in total yields of early autumn, showing no significance through, when compared with those of ron-thin out treatment. Whereas the total yields of early autumn and late autumn showed 12% increase with significance at the level of 5% by thin out treatment. (3) As above mentioned, the thin out of mulberry branches brought about a good effect on yields of mulberry leaves, though less on average length of branches. It may be considered that the thin out treatment makes improve the living condition in mulberry trees and in turn induces photosynthesis actively, which results in increase the weight of leaves.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.44-44
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• 2017

Recently, the occurrences of extreme flooding and drought, often in the same areas, have increased due to climate change. We tested the hypothesis that wetland species could help upland species under flood conditions; that is, the roots of wetland crops may supply $O_2$ to the roots of upland crops by a series of experiments conducted in both humid Japan and semi-arid Namibia (See Iijima et al, 2016 and Awala et al, 2016). Firstly, flooding tolerance of upland-adapted staple crops-pearl millet (Pennisetum glaucum) and sorghum (Sorghum bicolor) mix-cropped with rice (Oryza spp.) was investigated in glasshouse and laboratory experiments in Japan. We found a phenomenon that strengthens the flood tolerance of upland crops when two species-one wetland and one drought tolerant-were grown using the mixed cropping technique that results in close tangling of their root systems, hereinafter referred to "close mixed-planting". This technique improved the photosynthetic and transpiration rates of the upland crops subjected to flood stress ($O_2$-deficient nutrient culture). Oxygen transfer was suggested between the two plants mix-cultured in water, implying its contribution to the phenomenon that improved the physiological status of upland crops under the simulated flood stress. Secondly, we further tested whether this phenomenon would be expressed under field flood conditions. The effects of close mixed-planting of pearl millet and sorghum with rice on their survival, growth and grain yields were evaluated under controlled field flooding in semi-arid Namibia during 2014/2015-2015/2016. Single-stand and mixed plant treatments were subjected to 11-22 day flood stress at the vegetative growth stage. Close Mixed-planting increased seedling survival rates in both pearl millet and sorghum. Grain yields of pearl millet and sorghum were reduced by flooding, in both the single-stand and mixed plant treatments, relative to the non-flooded upland yields, but the reduction was lower in the mixed plant treatments. In contrast, flooding increased rice yields. Both pearl millet-rice and sorghum-rice mixtures demonstrated higher land equivalent ratios, indicating a mixed planting advantage under flood conditions. These results indicate that mix-planting pearl millet or sorghum with rice could alleviate flood stress on dryland cereals. The results also suggest that with this cropping technique, rice could compensate for the dryland cereal yield losses due to field flooding. Mixed cropping of wet and dryland crops is a new concept to overcome flood stress under variable environmental conditions.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.16
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• pp.6813-6823
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• 2015

Glioblastoma, also known as glioblastoma multiforme (GBM), is the most aggressive of human brain tumors and has a stunning progression with a mean survival of one year from the date of diagnosis. High cell proliferation, angiogenesis and/or necrosis are histopathological features of this cancer, which has no efficient curative therapy. This aggressiveness is associated with particular heterogeneity of the tumor featuring multiple genetic and epigenetic alterations, but also with implications of aberrant signaling driven by growth factors. The transforming growth factor ${\beta}$ ($TGF{\beta}$) superfamily is a large group of structurally related proteins including $TGF{\beta}$ subfamily members Nodal, Activin, Lefty, bone morphogenetic proteins (BMPs) and growth and differentiation factor (GDF). It is involved in important biological functions including morphogenesis, embryonic development, adult stem cell differentiation, immune regulation, wound healing and inflammation. This superfamily is also considered to impact on cancer biology including that of GBM, with various effects depending on the member. The $TGF{\beta}$ subfamily, in particular, is overexpressed in some GBM types which exhibit aggressive phenotypes. This subfamily impairs anti-cancer immune responses in several ways, including immune cells inhibition and major histocompatibility (MHC) class I and II abolishment. It promotes GBM angiogenesis by inducing angiogenic factors such as vascular endothelial growth factor (VEGF), plasminogen activator inhibitor (PAI-I) and insulinlike growth factor-binding protein 7 (IGFBP7), contributes to GBM progression by inducing metalloproteinases (MMPs), "pro-neoplastic" integrins (${\alpha}v{\beta}3$, ${\alpha}5{\beta}1$) and GBM initiating cells (GICs) as well as inducing a GBM mesenchymal phenotype. Equally, Nodal promotes GICs, induces cancer metabolic switch and supports GBM cell proliferation, but is negatively regulated by Lefty. Activin promotes GBM cell proliferation while GDF yields immune-escape function. On the other hand, BMPs target GICS and induce differentiation and sensitivity to chemotherapy. This multifaceted involvement of this superfamily in GBM necessitates different strategies in anti-cancer therapy. While suppressing the $TGF{\beta}$ subfamily yields advantageous results, enhancing BMPs production is also beneficial.

• Fisheries and Aquatic Sciences
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• v.20 no.11
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• pp.30.1-30.10
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• 2017

Small-scale fish farmers in developing countries are faced with challenges owing to their limited information on aquaculture management. Nile tilapia farmers in Teso North Sub-County recorded lower yields than expected in 2009 despite having been provided with required inputs. Water quality was suspected to be the key factor responsible for the low yields. This study sought to assess the effects of earthen pond water physico-chemical parameters on the growth of Nile tilapia in six earthen fish ponds under semi-intensive culture system in Teso North Sub-County. The study was longitudinal in nature with pond water and fish being the units of analysis. Systematic sampling was used to select five ponds while a control pond was purposively selected based on its previously high harvest. Four ponds were fed by surface flow and two by underground water. Each pond was fertilized and stocked with 900 fry of averagely 1.4 g and 4.4 cm. Physico-chemical parameters were measured in-situ using a multi-parameter probe. Sixty fish samples were randomly obtained from each pond fortnightly for four months using a 10 mm mesh size and measured, weighed and returned into the pond. Mean range of physico-chemical parameters were: dissolved oxygen (DO) 4.86-10.53 mg/l, temperature $24-26^{\circ}C$, pH 6.1-8.3, conductivity $35-87{\mu}S/cm$ and ammonia 0.01-0.3 mg/l. Temperature (p = 0.012) and conductivity (p = 0.0001) levels varied significantly between ponds. Overall Specific Growth Rate ranged between 1.8% (0.1692 g/day) and 3.8% (1.9 g/day). Ammonia, DO and pH in the ponds were within the optimal levels for growth of tilapia, while temperature and conductivity were below optimal levels. As temperature and DO increased, growth rate of tilapia increased. However, increase in conductivity, pH and ammonia decreased fish growth rate. Temperature and DO ranging between 27 and $30^{\circ}C$ and 5-23 mg/l, respectively, and SGR of 3.8%/day and above are recommended for higher productivity.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.2
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• pp.92-97
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• 1983

This experiment was designed to establish the soil physical improvement practice to increase the rice yields at fine textured fluvio-marine paddy field. After chiseling and trenching the paddy soil, the rice growth and soil physical properties were investigated for 4 years. The results are summarize as follows; 1. The soil physical properties, such as bulk density, hardness, porosity and permeability were prominently improved by trenching and chiseling. 2. There were significant relationships among the soil physical properties, root developments and rice yields. 3. The increasing rates of rice yields by soil physical improvement were about 10%, which is better than 5% of drainage effects. 4. The effects of trenching and chiseling on rice yields were continued to fourth year. Even if trenching effects was better than chiseling the chiseling was considered as a useful treatment for its simple working practice by using a heavy machine. 5. In case of trenching, straw application were increased the rice yields.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.2
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• pp.112-126
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• 1991

The atmospheric carbon dioxide concentration is ever-increasing and expected to reach about 600 ppmv some time during next century. Such an increase of $CO_2$ may cause a warming of the earth's surface of 1.5 to 4.5$^{\circ}C$, resulting in great changes in natural and agricultural ecosystems. The climatic scenario under doubled $CO_2$ projected by general circulation model of Goddard Institute for Space Studies(GISS) was adopted to evaluate the potential impact of climate change on agroclimatic resources, net primary productivity and rice productivity in Korea. The annual mean temperature was expected to rise by 3.5 to 4.$0^{\circ}C$ and the annual precipitation to vary by -5 to 20% as compared to current normal climate (1951 to 1980), resulting in the increase of possible duration of crop growth(days above 15$^{\circ}C$ in daily mean temperature) by 30 to 50 days and of effective accumulated temperature(EAT=∑Ti, Ti$\geq$1$0^{\circ}C$) by 1200 to 150$0^{\circ}C$. day which roughly corresponds to the shift of its isopleth northward by 300 to 400 km and by 600 to 700 m in altitude. The hydrological condition evaluated by radiative dryness index (RDI =Rn/ $\ell$P) is presumed to change slightly. The net primary productivity under the 2$\times$$CO_2$ climate was estimated to decrease by 3 to 4% when calculated without considering the photosynthesis stimulation due to $CO_2$ enrichment. Empirical crop-weather model was constructed for national rice yield prediction. The rice yields predicted by this model under 2 $\times$ $CO_2$ climatic scenario at the technological level of 1987 were lower by 34-43% than those under current normal climate. The parameters of MACROS, a dynamic simulation model from IRRI, were modified to simulate the growth and development of Korean rice cultivars under current and doubled $CO_2$ climatic condition. When simulated starting seedling emergence of May 10, the rice yield of Hwaseongbyeo(medium maturity) under 2 $\times$ $CO_2$ climate in Suwon showed 37% reduction compared to that under current normal climate. The yield reduction was ascribable mainly to the shortening of vegetative and ripening period due to accelerated development by higher temperature. Any simulated yields when shifted emergence date from April 10 to July 10 with Hwaseongbyeo (medium maturity) and Palgeum (late maturity) under 2 $\times$ $CO_2$ climate did not exceed the yield of Hwaseongbyeo simulated at seedling emergence on May 10 under current climate. The imaginary variety, having the same characteristics as those of Hwaseongbyeo except growth duration of 100 days from seedling emergence to heading, showed 4% increase in yield when simulated at seedling emergence on May 25 producing the highest yield. The simulation revealed that grain yields of rice increase to a greater extent under 2$\times$ $CO_2$-doubled condition than under current atmospheric $CO_2$ concentration as the plant type becomes more erect.