• Asian Journal of Turfgrass Science
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• v.13 no.1
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• pp.1-20
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• 1999

This study was carried out to investigate the interaction between productivity and light condition and to analyze the material productivity and productive charactaristics under different hours of light in Zoysia japonica. 1. Rate increasement of leaf number and total leaf length was remarkably high at the early growth stage in the control and 9 hour light treatment. The rate gradually decreased as growth proceeded. But 3 hour treatment was very low in the rate from its early growth stage through the whole test period. 2. The increasing rate of leaf area ratio (LAR) in all the experimental plots was remarkably high at the early growth stage after transplanting the grass. The shorter photoperiod resulted remarkable lower increasement of LAR. 3. The rhizome growth rate of the 9 hour photoperiod was high contrast to the 3 hour photoperiod treatment. The increasing rate of node number was also showed similar trend. 4. Chlorophyll content was very high at the 36 days after transplanting and then decreased gradually. Chlorophyll content on 3 hours photoperiod plot severely decreased. The ratio of chlorophyll a to b was decreased significantly at short day treatment. 5. The content of soluble sugar was increased at shorter photoperiod. The highest ratio of sugar content was on August, 28 by HPLC method. Such a result was attributed to accumulation of sugar in spite of low synthesis of ploysacchrides, translocation by low consumption. 6. The increasing rate of standings in all light treatment was high at the early growth stage after transplanting. Short photoperiod treatment by 3hour showed especially low prganic productivity on Zoysia japonica.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.314-339
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• 1982

Fluctuating climate is still most important environmental constrain, although improved modem agricultural technology has succeeded to increase crop production in the world. To stabilize the food production under fluctuating weather conditions, it is very needed to obain the quantitative information of interactions between crops and climate. The main purpose of this paper is three hold. Using the JIBP-data, the dry matter accumulation of rice crops is studied in relation to weather indexes (\SigmaTa and \SigmaSt). Temperature dependence of the yield index of rice is analyzed as to air temperature and water temperature. \SigmaT$_{10}$ -fluctuations are studied using meteorological data at various stations. The possible shift of \SigmaT$_{10}$ -isopleths due to climate fluctuation is evaluated. The second interest is in the plant climate of rice crops. Using results of canopy photosynthesis, it is pointed that the canopy structure has most important implication in plant climate. Leaf-air, stomatal, and mesophyll resistances of rice crops are described in relation to weather conditions. The change in light condition and aerodynamical property of rice crops with the growth is illustrated. The energy partition is also studied at different growing stages. Third point is to show in more detail effective countermeasures against cold irrigation water and cool summer. Heat balance of warming pond and polyethylene tube as a heat exchanger is studied to make nomo-grams for evaluating the necessary area and necessary length. Effects of windbreak net on rice crops are illustrated by using experimental and simulation results.lts.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.3
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• pp.211-217
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• 1990

This study was carried out to elucidate the effect of different time and severity of defoliation on the dry matter accumulation in grain of rye (cv, Paldanghomil) and triticale (cv, Sinkihomil). The weight of the 2nd leaf blade was the greatest and this was followed by the 3rd and flag leaf in that order. The chlorophyll content in leaf blade and sheath were decreased at lower leaf position (flag > 2nd > 3rd). The average chlorophyll content of rye was higher than that of triticale. The earlier and severer defoliation was made, the more grain weight was its was decreased. As the time of defoliation was made later and the degree of its was small, 1,000 grain weight was increased. The results showed that the effect of defoliation on 1,000 grain weight followed the order of the flag, the 2nd and the 3rd leaf. The greatest 1,000 grain weight was observed at the middle part of panicle, which followed by the top and bottom part in that order.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.4
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• pp.226-231
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• 1992

This experiment was carried out to estimate the dry matter accumulation using growth analysis in spring growth of perennial ryegrass varieties grown under space planting conditions, based on the data of previous paper9'. The results obtained were as follows: 1. Growth parameters of leaf area ratio(LAR), specific leaf area(SLA) and leaf weight ratio(LWR) were recognized siginificant differences between varieties. But, specific leaf area(SLA), leaf weight ratio (LWR) and relative tiller appearance rate(RTAR) were recognized significant differences between growth stages. Specific leaf area(SLA) was significant difference for the interaction of variety Xgrowth stage. 2. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with relative growth rate of shoot(RGR) and root(RWGR), and net assimilation rate(NAR) as affected by the varieties and growth stages. 3. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlation with nct assimilation rate(NAR) in all varieties. Leaf area ratio(LAR) had significantly positive correlation with specific leaf area(SLA) in all varieties, but shows a significant negative correlation with leaf weight ratio(LWR) of Maprima variety. 4. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with the absolute growth rates of yield components.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.121-127
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• 2005

To reveal vegetation history and environmental changes in Mt. Jiri, sediment cores were collected from Wangdeungjae moor of Mt. Jiri. Overall dry matter accumulation rates and sedimentation rates by $^{14}C-dating$ were 0.027 $kg{\cdot}m^{-2}{\cdot}yr^{-1}$ and 0.184 mm/yr since 1250 ($760{\pm}40$ yrs BP, 14 cm in depth). There are three pollen zones; the first zone is below 14 cm depth where Quercus dominated, the second zone is from 14 cm to 6 cm depth where Gramineae increased and Quercus and Salix dominated and the third zone is from 6 cm depth to the top where Pinus and Quercus dominated. Total pollen concentration gradually increased from bottom to the top of sediment core, which implies wet, anaerobic and cool condition during covered period by the core. Calcium and magnesium contents had increased since 14 cm depth, with peaks at 13 and 20 cm depths. This indicates that groundwater had recently become relatively more important than surface water as water source of Wangdeungjae moor Exotic plant or Chenopodiacea pollen was less than 1%. There was little variation in total N and P contents along the length of the core. These results support that Wangdeungjae moor has been little affected by anthropogenic activities. Also, nutrients and heavy metal contents indicate the baseline condition of Wangdeungjae moor.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.2
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• pp.129-133
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• 1999

Excessive soil water at vegetative growth stages during the rainy season induces yield losses in soybeans. Our objectives were to obtain basic information about the cultivar differences and to understand the stress-tolerance process for due to excessive soil water. Previous experiments revealed soybean genotypic differences in tolerance to excessive soil water. A field experiment was conducted at the Research Farm of Korea University near Seoul on 21 May 1998. Soybean[Glycine max (L.) Merrill] cultivars, 'Hannamkong' (sensitive) and 'Taekwan-gkong'(tolerant) were planted in vinyl-lined plots(1.2 x 4.2 x 0.3 m deep) and control plots. Drip irrigation began at VI growth stage to submerge the soil surface. Three weeks of excessive soil water treatment reduced all growth parameters measured to soybean plants. Excessive soil water stress resulted in decreases of N, P, K, Ca, Mg and Cu, and increases of Fe and Mn contents in soybean leaves. The stress index of tolerant cultivars under excessive soil water showed no large difference in soybean growth characteristics measured at three growth stages. However, K, Ca, Mg, Fe and Mn contents in soybean leaves appeared to differ between sensitive and tolerant cultivars. From the above results, stress and tolerance indices are proposed for a method to test cultivar differences in plant responses within a species under adverse growth environments.

• Journal of agriculture & life science
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• v.43 no.4
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• pp.15-20
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• 2009

The transition from pregnancy to lactation, commonly referred to as the "transition period" is characterized by dramatic changes in metabolic processes and their regulation in order to prepare the dairy cow for parturition and lactogenesis. An important adaptation to lactation is the increase in gluconeogenesis by the liver to meet the tremendous increase in demand of glucose for lactose synthesis, and the accumulation of lipid in adipose tissue during pregnancy, its mobilization that begins prior to lactation and the dramatic increase in plasma NEFA concentration early lactation. Epinephrine and insulin, the homeostatic regulators of metabolism are responsible for the adaptations of lipid and carbohydrate metabolism in support of milk production along with mobilization of body fat to meet overall energy demands because dry matter intake is insufficient to meet these demands during early lactation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.179-184
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• 1986

The pot trial was carried out to investigate the influence of soil temperature on the growth and dry matter accumulation in sorghum cv. Pioneer 931 and corn cv. Suweon 19 during their growing season in 1985. Soil temperature maintained with low ($22.3^{\circ}C$), natural($25.9^{\circ}C$) and high temperature($30.5^{\circ}C$) over 24 hour. The results are summarized as follows; 1. Growth of sorghum plants was associated with increasing of soil temperature, while that of corn was reduced under high temperature($30.5^{\circ}C$). The highest plant height of corn was found at natural temperature($25.9^{\circ}C$). Sorghum had higher growth rate than corn plants in all temperature levels. 2. Assimirable leaf areas of the plants were greately increased under high temperature both in sorghum and corn. Sorghum plants maintained almost same levels of leaf area during maturity stage, but those of corn were markedly decreased after mild stage. 3. The highest rates of photosynthesis were found at nature' soil temperature ($25.9^{\circ}C$) both in sorghum($1.619mg/s/m^2$) and corn plants($1.084mg/s/m^2$). Under high temperature($30.5^{\circ}C$) the photosynthesis rates of the plants were decreased to about 1.553 mg and 0.404 mg for sorghum and corn, respectively. Low temperature ($22.3^{\circ}C$) produced only a value of 0.775 mg for sorghum and 0.048 mg for corn. 4. Seasonal dry matter accumulation of sorghum increased in the order of high>natural>low soil temperature, but that of corn increased in the order of natural>high>low soil temperature, respectively.

• Journal of Forest and Environmental Science
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• v.11 no.1
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• pp.72-80
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• 1995

Altitudinal effects on the accumulation of O layer were examined for deciduous broad-leaved forests in the experimental forest of Kangwon National University. There found a marked increased towards the higher altitudes in the thickness of O layer. These trends could be observed conspicuously on the F2 and H layers. The relation between thickness (X, cm) and dry weight (Y, $kg/m^2$) of O layer was approximated by linear regression equations;Y($kg/m^2$ = aX(cm). The values of coefficient "a" for the F2, H and F2+H layers were 0.43, 0.61 and 0.53, respectively. Bulk densities of the accumulated organic matter estimated nearly to be $45g/dm^2$ in F2 layer, $60g/dm^2$ in H layer and $55g/dm^2$ in F2+H layer. The amount of O layer ranged from 13ton/ha for the forest at 280m in altitude to 41ton/ha for the upper forest at 710m in altitude. Among these total amount of the O layer, F1, F2 and H layer occupied to be 5~10ton/ha, 5~11ton/ha and 13~40ton/ha, respectively.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.142-147
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• 2009

In this study, the selenium (Se) accumulations of soybean sprouts and mungbean sprouts treated with various concentrations of Se-solutions were evaluated, as part of a broader effort to produce Se-enriched variants of the plants. Four levels of sodium selenate ($Na_{2}SeO_{4}$)-dissolved solutions (i.e. 0, T0; 6, T1; 60, T2; and $600{\mu}g/mL$, T3) were prepared and sprayed onto the plants during cultivation. The effect of different spraying periods on Se accumulation was also assessed by watering plant groups once a day for periods of one, two, or three days. Se solution remaining on the surfaces of the plants was washed out by spraying with distilled water on the final day of cultivation. However, the increase of Se accumulation in the plants was found to depend on both Se-concentration and watering period, and the soybean sprouts were determined to accumulate Se more effectively than the mungbean sprouts. Additionally, with regard to Se accumulation in the plants, the period of application of Se solution was determined to be more important than the concentration of the Se solution applied. The averaged total levels of Se-enrichment in whole soybean sprouts at T0, T1, T2, and T3 were 0.26, 65.86, 179.62, and $525.12{\mu}g/dry$ matter (DM) g, respectively, and the relative equations relating Se enrichment in soybean sprouts (Y) against watering days (X) were Y=32.505X-36.17 (T1), Y=88.46X-92.04 (T2), and Y=251.11X-254.9(T3). The averaged total levels of Se-enrichment in the whole mungbean sprouts at T1, T2, and T3 group were 0.05, 3.64, and $101.43{\mu}g/DM$ g, respectively, and the relative equations relating Se enrichment (Y) to watering days (X) for mungbean sprouts were Y=1.67X-1.3467 at T1 and Y=48.035X-46.907 at T2. The results of this study suggest that soybean sprouts and mungbean sprouts enriched with bioavailable Se can be produced on a large scale by Se supplementation, allowing for the development of healthy functional foods such as Se-enriched mungbean sprout soups and salads, Se-enriched functional drink and food additives, and selenium tablets to promote health.