• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.40-47
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• 1987

Under the different conditions of planting density and compound fertilizer level, some agronomic and chemical characteristics of burley tobacco were investigated from 1982 to 1984. Leaf area and dry leaf weight per plant, crop growth rate, relative growth rate and net assimilation rate for 40-60 days after transplanting were higher with increasing plant spacing and fertilizer, but leaf area index was lower with increasing plant spacing. At topping stage, the leaf size was increased with increasing plant spacing and amount of fertilizer applied and the stem diameter was increased by increasing plant spacing. Leaf area, leaf weight per plant and weight per unit leaf area of harvested leaf were higher when plant spacing and fertilizer increased. It was estimated that the optimum plant spacing was 105cm x 34cm and level of com-pound fertilizer (N-P$_2$ O$\sub$5/ -K$_2$O =10-10-20) was 263kg/l0a for high yield. There were trends toward increase the contents of total alkaloid and total nitrogen with increasing plant spacing and fertilizer application. There was significant positive correlation between plant spacing and total nitrogen, and between fertilizer application and total nitrogen. The plant spacing of 105cm x 35 to 40cm and 227.5kg/l0a of fertilizer level may be profitable for farm economy and the low nitrogenous leaf.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.461-468
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• 2012

This study was conducted to study the seasonal changes of relative water relations parameters by pressure-volume curves of Korean mistletoe (Viscum album var. coloratum) leaves for understanding ecological characteristics. In growing season, the osmotic potentials at full turgor (${\Psi}_o^{sat}$) and at incipient plasmolysis (${\Psi}_o^{tlp}$) decreased, while increased the maximum bulk elastic modulus of the cell wall ($E_{max}$) and relavive water content ($RWC^{tlp}$). Korean mistletoe in Quercus variabilis and Korean mistletoe in Quercus mongolica in November showed best maximum perssure potential (${\Psi}_{P,\;max}$). Pressure potential (${\Psi}_P$) and water potential (${\Psi}_L$) in Korean mistletoe in Quercus variabilis were rapidly decreased with decreasing of relative water content. The values of $RWC^{tlp}$ in November were all above 84% showing that the function of osmoregulation is somewhat better, and symplastic water content (Vo/DW) and maximum water content (Vt/DW) were variable seasonally. Thus, responses to water relations of Korean mistletoe in Quercus variabilis and Korean mistletoe in Quercus mongolica such as ${\Psi}_o^{sat},\;{\Psi}_o^{tlp},\;E_{max},\;{\Psi}_{P,\;max},\;RWC^{tlp}$ showed increaing drought tolerance with increasing of leaf aging.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.49-55
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• 1978

In order to get healthy seedling of rice suitable for rice transplanter, the growing characteristics of the seedling grown under different growing days and sowing densities were invesigated and the results obtained were summarized as follows; In the 20 days old seedling, the difference of growing state of seed ling and its characteristics between the two types of nursery bed was not found, but for the 30 days old seedling, both of the crop growth rate and the relative growth rate on the band-type nursery bed appeared higher than those on the mat-type nursery bed. And also, "the dry weight, the content of cardohydrate and the ratio of dry weight to plant height of the seedling grown on the band-type nursery bed were much higher than those on the mat-type nursery bed, however the amount of difference of seedling characteristics between two types of nursery bed was decreased for 40 days old seedling and leaf number was not increased. The amount of the seedling growth was increased with less density of sowing and for the difference between the higher and the less density, the difference getting bigger with the longer nursery days. The maximum density of sowing was approximately 200cc per nursery case on the band-type nursery bed and 250cc per nursery case on the mat-type nursery bed. It was seemed that the growing uniformity of the seedling grown on the mat-type nursery bed was better than that on the band- type nursery bed, As the coefficient of variation of the plant height and the leaf numbers of the seedling grown on the band- type nursery bed was higher than that on the mat-type nursery bed.

• Journal of Plant Biology
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• v.24 no.1
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• pp.1-12
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• 1981

Phosphorus dynamics in terms of specific absorption rate, inflow and outflow rates. turnover rate, demand and supply, and utility index of a high yield Zea mays L. cv. Bokgyo field were evaluated using an analysis of successive production structures. The analysis was adopted for measuring quantitative changes in the population by stratified clip technique on every two weeks during the growing season. The seasonal trends of specific absorption rate (2. 4 mg P/g/day in maximum) and specific absorption efficiency (0. 03) closely correlated with that of relative growth rate of the population. The overall inflow and outflow of phosphorus was 3.41 g P/$m^2$/yr showing the maximum inflow of 2.99 g P/$m^2$/month in July. While the maximum phosphorus standing crop was 1.4 g P/$m^2$ showing the maximum turnover rate of 178% in late June. The accumulation of phosphorus along plant height declined monotonically in stems and roots but increased in foliage after heading. The proportions of the total annual demand of phosphorus were 24.4% for leaves, 22.5% for stems, 49.6% for fruits and 3.5% for roots. These demands were met with internal (18.2 %) and external (81.8 %) supplies. The seasonal highest phosphorus utility index was 1,091 in early June, while the average value was 655.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.183-200
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• 1989

An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.2
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• pp.151-158
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• 2011

This study was carried out in 2010 to investigate the utilization and nutritive value of native grasses, such as Phragmites communis and Miscanthus sinensis which might reduce the cost of feeding domestic cattle. The regions within the Civilian Control Line in Paju and Sihwa region in Ansan were surveyed. In Paju, the yearly silage production was 900 MT harvested from 90 ha (10 MT/ha). About 30~50% of these were sold out at the marketing price of 52,000~55,000 Won per roll (130~137.5 Won/kg). Regrown Miscanthus sinensis of 70 cm in length contained 9.6% of crude protein (CP), 82.4 of relative feed value (RFV), and 67.7% of in vitro dry matter digestibility (IVDMD). Regrown Phragmites communis of 70 cm in length contained 13.8% of CP, 84.3 of RFV, and 67.9% of IVDMD. As harvesting was delayed, the quality was decreased dramatically. In Ansan region, Phragmites communis plantation covers 100 ha. The silage production was 550 MT from the area of 50 ha (11 MT/ha) in 2009. And the marketing price was 50,000 Won per roll. But in 2010 only a small amount of grasses could have been baled due to frequent and much rainfall from spring to summer season. However, the good forage quality was observed from regrown Phragmites communis of 80 cm in length, 12.9% CP, 99.8 RFV and 66.6% IVDMD, while that of late matured grasses was very low, 2.2% CP, 52.9 RFV and 36.4% IVDMD, greatly lower than forage quality of rice straw. The quality of grasses at bloom stage of 150 cm in length was similar to that of rice straw, showing 4.5% CP, 59.9 RFV and 42.2% IVDMD. In conclusion, the overall quality of most native grasses in this survey were very poor. Therefore, we recommend that Phragmites communis and Miscanthus sinensis should be harvested during June or July to obtain better forage quality which is richer in forage values than rice straw. Production of high quality forage crops was also desirable for self sufficiency of forage.

• Korean Journal of Plant Resources
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• v.15 no.2
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• pp.107-113
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• 2002

This study was performed to obtain the information on fruit set, propagation and flowering habits of the exotic ornamental bottle brush tree (Callistemon citrinus). Trees have fruit capsules for four years since the fruit set and they have enlarged for three years. While 2 and 3-year-old capsules have similar seeds in number and size, 1-year-old ones have fewer and smaller seeds. Most dried capsules open when they have 75％ relative water contents. Two year old seeds which they were dried at 30％ germinated better than others. Removal of capsule bearing twigs resulted in greatly increased subsequent flower numbers (an average of 14 flowers per tree) compared with twigs where seed capsule were allowed to remain. In cutting for propagation, semi-hard wood branches dipped in 100mgι$^{-1}$ IBA for 24 hours rooted at 86.4 ％ and had an average of 12.6 primary roots.

• Journal of Practical Agriculture & Fisheries Research
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• v.6 no.1
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• pp.81-89
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• 2004

The effects of developed grape bags on the micro-climate changes of bag, physiological disorder, pathogenic decay, quality and harvest time evaluation in 'Campbell Early' grapevines were studied. The temperature and light transmittance of developed grape bags showed no differences compared with the onces of conventional bag and non-bagging, but relative humidity and the amount of water evaporation were changed in all treatments. The occurrence of unfertilized fruit, poorly colored fruit, russet and gray mold rot showed no significant difference in all treatment at harvest time. Developed grape bags decreased effectively the occurrence of cracking fruit and bitter rot in 'Campbell Early' fruit. There was no difference in growth of cluster and berry, soluble solids and total acidity in fruits, degree of skin color and bloom appearance at harvest time. The skin color and fruit boom and harvest time evaluation in developed grape bags were resulted excellent compared with the once of conventional bag and non bagging.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.3
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• pp.312-317
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• 1985

Growth response and nutrients uptake of tobacco grown on mulched and non mulched plots were investigated during the growing period. 1. The whole growing time was about 25 days shorter and relative growth rate was faster in the mulched plot than in the non mulched plot. 2. Nitrate content of leaf in the latter stage of tobacco grown on the non mulched plot was more continuously increased compared with mulched plot. As a result in the latter stage of tobacco leaf nitrate form of nitrogen level was much higher on non mulched plot than on mulched plot. 3. Reducing sugar content in cured leaves of tobacco grown on the non mulched plot was lower that of the mulched plot. This difference in reducing sugar content was remarkable in the bottom leaves that nitrate content was highest. 4. Tobacco growing on nonmulched soil may cause to be low quality owing to increasing of nitrogen compound and decreasing of reducing sugar content in cured leaves. 5. As distributions of nitrate and potassium content in leaves at different stalk position was similar each other, nitrate and potassium ion considered to be counter ion in absorption and translocation through the tobacco plant.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.385-392
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• 2009

This study was performed to evaluate the influence of temperature, relative humidity, and light conditions during healing and acclimatization on the graft-take and growth of grafted peppers (Capsicum annuum L.), in order to propose optimum environmental conditions for the healing and acclimatization of grafted peppers. The healing and acclimatization period was for six days and was divided into three stages (Stage I, II and III), of which each period was two days. Grafted peppers were healed under the condition of 30 and 95% relative humidity (RH) during Stage I. During Stage II and III, grafted peppers were healed and acclimatized under different temperatures ($20^{\circ}C$, $25^{\circ}C$, or $30^{\circ}C$) and RH conditions (75%, 85% or 95%). The growth of grafted peppers was greater under lower temperature and lower relative humidity conditions. The graft-take just after the end of healing and acclimatization was greater grafted peppers under high RH condition. However, the graft-take of peppers which were healed and acclimatized under $30^{\circ}C$ and RH 95%, dropped by about 10 percent on day seven after healing and acclimatization. And also, grafted peppers were healed and acclimatized under the different temperatures ($25^{\circ}C$ or $30^{\circ}C$), RH conditions (65%, 75% or 85%), and light condition (dark or light). Lower RH (to 65%) and light condition at $25^{\circ}C$ during healing and acclimatization promoted the graft-take and growth of grafted peppers.