• Weed & Turfgrass Science
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• v.4 no.4
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• pp.338-347
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• 2015

Reinforcement cells are used to aid grass growth and taken together, this serves to extend greenery beyond the conventional spaces of lawns, tree pits, gardens, and parks, and is advantageous to urban cities since space for greening is often limited. Drought has variable effects on plant life and the resilience of turf to drought resistance also varies with species. Changes in photosynthetic ability were more pronounced for media rather than grass species. The media of sand without organic matter was found to be least suited for drought resistance. Normalized difference vegetation index (NDVI) and digital image analysis (DIA) data were generally in favour of Zoysia species as oppose to A. compressus. In A. compressus, selective traits such as, a more extensive root system and lower specific leaf area (SLA) were not an underlying factor that assisted this grass with enhanced drought resistance. Generally, WUE was found to be strongly related to plant characterises such as overall biomass, photosynthetic features as well as the lushness indexes, and specific leaf area. This study found a strong relationship between WUE and a suite of plant characteristics. These traits should serve as useful selection criteria for species with the ability to resist water stress.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.314-321
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• 2018

Durum (Triticum turgidum L. ssp. durum) is a major crop species cultivated for human consumption worldwide. In Tunisia, salt stress is one of the main problems that limit crop production. 'Mahmoudi' was selected as the most salt-sensitive out of 11 Tunisian durum cultivars. Using the salt-tolerant cultivar 'Om Rabia', resistant and susceptible cultivars were evaluated to compare genetic responses under salt stress. At the fully expanded third leaf stage, salt stress was applied by submerging the pots in 500 mM NaCl for 5 min every day for saline water irrigation in the greenhouse. The treatment was applied for 1 week and salt stress tolerance was determined by changes of growth parameters to the control condition. The salt tolerance trait index and salt tolerance index were calculated and used as selection criteria. The expression levels of TdHKT1;4, TdHKT1;5, and TdSOS1 were examined using qPCR. For further evaluation of physiological responses, salt stress (150 mM NaCl) was additionally applied for 48 h at the fully expanded third-leaf stage. Increased expression of the genes responsible for salt tolerance and proline content in tolerant durum can be used to broaden genetic diversity and provide genetic resources for the durum breeding program.

• The Journal of the Korea Contents Association
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• v.4 no.4
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• pp.141-152
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• 2004

In this paper, we propose the index structure supporting the future position retrievals with efficiently updating continuous positions of moving objects in location based services. For reducing update costs of moving objects, our index structure directly accesses to the leaf node with moving objects using secondary index structure and performs bottom up update when node information is changed. Positions of moving objects are stored in primary index structure. In primary index structure, the split information similar to kd-tree is stored to internal node for increasing node's fanout. And the proposed index structure supports the future position retrievals using velocity of moving objects in the child node.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.5
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• pp.309-318
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• 2005

Higher level of KCl application stimulated both leaf area index and leaf area duration in all cassava varieties, while the leaf and tuber number of the bitter varieties (high cyanide-level varieties) decreased in proportion to the level of KCl application. The root/shoot (R/S) ratio and harvest index (HI) were negatively related with the level of KCl application in all cassava varieties. The bitter varieties obtained the lowest R/S ratio at the level of 100 - 150 kg KCl $ha^{-1}$, while the sweet varieties (low cyanide-level varieties) acquired the highest values at the level of 50 - 150 kg KCl $ha^{-1}$. Also, the sweet varieties showed the lowest HI at the level of 250 kg KCl $ha^{-1}$, but the bitter varieties at the level of 150 kg KCl $ha^{-1}$. At 6 - 8 months after planting, the sweet varieties tended to obtain higher starch content of roots (tubers) at the level of 50 - 150 kg KCl $ha^{-1}$, while the bitter varieties at the level of 150 - 250 kg KCl $ha^{-1}$. Relatively lower level of 50 - 150 kg KCl $ha^{-1}$ was more appropriate for decreasing hydrocyanic acid (HCN) content of roots (tubers) in the sweet varieties at the harvest time, and the level of 250 kg KCl $ha^{-1}$ was adequate to decrease not only HCN content of leaves but also that of roots (tubers) in the bitter varieties during the growing period. To obtain higher yield and starch content of tubers, and lower HCN content of roots (tubers), it was recommended that the sweet varieties are applied with the level of 50 - 100 kg KCl $ha^{-1}$ and the bitter varieties with the level of 150 - 200 kg KCl $ha^{-1}$, respectively, in Latosol soils of Bogor areas, West Java.

• The Korean Journal of Ecology
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• v.15 no.2
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• pp.103-115
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• 1992

This dissertation, which has been prepared in the region of cheju(33o31'N, 126o32'E) from may,1987 to appril, 1989, is to elucidate the dominant characteristics of early stages in secondary succession, by examining the life history of erigeron annuus for the seeding depth of a seed was dependent upon the degree of shading. That is, on the area of ocm,the more tense the shading was, the more germination percentage was increased, while, in the case of 1.5cm, it was somewhat increased, when shading bwcame ess and less tense. The rosette of e. annuus, through its relative light intensity was decreased by shading, up to 5% of natural light, showed some strong shade tolerance, which had no difficulty in matter production. The species diversity of mixed-species community was the highest in the middle of April, the lowest in the last of may. The dominance index was the highest in the late may, the lowest in the middle of April. Toward the end of may, the occupation rate of dominance species was the highest. There was a neutral relationship between intraspecific and interspecific, owing to the differentiation of its niche, temporally and spatially. Productive structure of the community revealed a narrow leaf type which was concentratively distributed in the mid part of community height. The relative light intensity of community ground surface was 6.1%, the leaf inclination 60o,the extinction coefficient(k) 0.4, biomass of community 1,045.6 g.d.w./m2,T/Rratio 9.3, C/Frate 7.0 and sumgermanition, shade toarance and community characteristics on erigeron annuus l.in chejumed leaf area index 3.88. through the various life cycles o e.annuus, we can say that it decreases mortality of seeding caused by some stress and disturbance, for germination lasts for a long time at any opportunity available, and it promotes population growth. The strong shade tolerance of a rosette and the variableness of a life from differentiate the niche between intraspecific and interspecific within the community, and avoid the direct competition between them, thus poromoting community growth.

• Proceedings of the SCSK Conference
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• 2003.09a
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• pp.672-685
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• 2003

Yew (Taxus cuspidata Sieb.) chose that grow as medicine, food, decorative plant in Korea's Kyong-Gi province surroundings. Extracts of yew extracted leaf of 250 g and stems of 300 g with 1,3-butylene glycol (1,3-BG), propylene glycol (PG) and water. As results, external appearance of leaf extract of yew was slightly brown clear extract. The pH was 5.3$\pm$0.5, and specific gravity was 1.012$\pm$0.05, and refractive index was 1.375$\pm$0.05. Also, appearance of stem's extract was slightly brown clear extract, and the pH was 5.4$\pm$0.5, and specific gravity was 1.016$\pm$0.05, and refractive index was 1.358$\pm$0.05. Oil of yew separated from seeds, and extracted polysaccharide high purity from fruits. As a result, specific gravity of oil was 0.987, and obtained 40％ of yield. Total polyphenols amount of yew extract is detected 0.563％ in leaves, 0.325％ in stems, whereas total tannins amount contained 0.054％ and 0.037％ each in leaves and stems. As effect in cosmetics, the anti-oxidative effect by DPPH method is 75.0％ in leaves, and stems was 64.0％. Collagen synthesis rate was shown high activity by 54.16％ in stem's extract, 33.18％ in leaves' extract. Also, PPE-inhibitory activities were 13.7％ and 23.5％ each in leaves and stems. Anti-inflammatory effect of yew seed oil displayed superior effect of 41 ％ than control. Polysaccharide's molecular weight that is gotten from fruits was 5$\times$10$^4$~ 3$\times$10$^{5}$ dalton, and got 20.0$\pm$5％ of yield.

• Journal of Plant Biology
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• v.12 no.2
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• pp.28-42
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• 1969

Field studies were conducted with the split plot design of 20 treatment with a combination of 4 levels of 3, 5, 7 and 9 plants per hill and 5 levels of 60, 80, 100, 120 and 140 hills per 3.3$m^2$ on non-, low- and high-salty areas. Rice variety, Kusabue was grown under jthe standard fertilization and cultivating. Investigation was made on the productive structure of plant population, leaf-area index, light intensity curve by stratum of crop population at the panicle differentiation stage. The competition density effect on the photosynthetic capacity was low as the salt concentration became higher. This seemed to suggest the possiblity of an increased yielding capacity by closer planting in the salty areas. The effect of an increased number of hills per unit area was greater than that of an increased unmber of plants per hill due to the total leaf area and space distribution of the actie assimilation parts of rice plants. The number of ppanicle per unit area in the salty areas were increased when the number of hill per 3.3$m^2$ increased over an increased number of plants per hill, and the panicle weight was reduced by close planting in the non-lalty area, while it was not reduced so much in the salty areas. The number of grains per panicle was significantly decreased by close planting in the salty areas as in the non-salty area, and ratio of matured grain was not decreased even by close planting in the salty areas, while it was significantly decreased by close planting in the non-salty area. An increase in the rice yield was possible by close planting and greatly related to leaf area index in the salty areas but not in the non-salty area. Increasing the number of hills per unit area showed greater effect on the increase of the rice yield than an increased number of plants per hill in the salty areas. Relationships between the growth characteristics and the rice population affected by plant spacing mode for maximum production were discussed.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.132-139
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• 2015

Bt-cotton germplasm, consisting of 75 genotypes was evaluated against cotton leaf curl disease (CLCuD) under high inoculum pressure in the field and using graft inoculation in glasshouse by visual symptom scoring assessments. None of the tested genotype was found disease free under both evaluation tests. Under field conditions in 2011, 3 genotypes were found resistant, 4 moderately resistant, 3 tolerant, 2 moderately susceptible and one susceptible; in 2012, 3 genotypes were tolerant, 7 moderately susceptible, 5 susceptible and 38 highly susceptible; in 2013, one was moderately susceptible and 51 were highly susceptible with varying degree of percent disease index (PDI) and severity index (SI). However, through graft evaluation in glasshouse, none of the graft inoculated plant was symptomless. All tested genotypes showed disease symptoms with SI values ranging between 5.0 and 6.0, and latent period between 12 and 14 days. Of the 75 genotypes evaluated using graft inoculation, 11 were found susceptible with SI values of 5.0 to 5.4 while remaining 64 were highly susceptible with SI values of 5.5 to 6.0. Inoculated plants of all tested genotypes exhibited severe disease symptoms within 10 days after the appearance of initial symptoms. No reduction in SI value was observed until the end of the experiment i.e., 90 days after grafting. Information generated under the present study clearly demonstrates that no sources of resistance to CLCuD are available among the tested Bt-cotton genotypes. So, a breeding programme is needed to introgress the CLCuD-resistance from other resistant sources to agronomically suitable Bt-cotton genotypes.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.4
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• pp.373-379
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• 2019

Smart-farm has been spreading across Korea to improve the labor efficiency and productivity of greenhouse crops. Although notable improvements have been made in the monitoring technologies and environmental-controlling systems in greenhouses, only a few simple decision-support systems are available for predicting the optimum environmental conditions for crop growth. In this study, a tomato growth model (GreenTom), which was developed by Seoul National University in 1997, was calibrated and validated to examine if the model can be used as a decision-supporting system. The original GreenTom model was not able to simulate artificial defoliation, which resulted in overestimation of the leaf area index in the late growth. Thus, an algorithm for simulating the artificial defoliation was developed and added to the original model. The node development, leaf growth, stem growth, fruit growth, and leaf area index were generally well simulated by the modified model indicating that the model could be used effectively in the decision-making of smart greenhouse.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.343-356
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• 2003

Yew (Taxus cuspidata Sieb.) chose that grow as medicine, food, decorative plant in Korea's Kyong-Gi province surroundings. Extracts of yew extracted leaf of 250 g and stems of 300 g with 1,3-butylene glycol (1,3-BG), propylene glycol (PG) and water. As results, external appearance of leaf extract of yew was slightly brown clear extract. The pH was 5.3$\pm$0.5, and specific gravity was 1.012$\pm$0.05, and refractive index was 1.375$\pm$0.05. Also, appearance of stem's extract was slightly brown clear extract, and the pH was 5.4$\pm$0.5, and specific gravity was 1.016$\pm$0.05, and refractive index was 1.358$\pm$0.05. Oil of yew separated from seeds, and extracted polysaccharide high purity from fruits. As a result, specific gravity of oil was 0.987, and obtained 40% of yield. Total polyphenols amount of yew extract is detected 0.563% in leaves, 0.325% in stems, whereas total tannins amount contained 0.054% and 0.037% each in leaves and stems. As effect in cosmetics, the anti-oxidative effect by DPPH method is 75.0% in leaves, and stems was 64.0%. Collagen synthesis rate was shown high activity by 54.16% in stem's extract, 33.18% in leaves' extract. Also, PPE-inhibitory activities were 13.7% and 23.5% each in leaves and stems. Anti-inflammatory effect of yew seed oil displayed superior effect of 41 % than control. Polysaccharide's molecular weight that is gotten from fruits was 5$\times$10$^4$~3$\times$10$^{5}$ dalton, and got 20.0$\pm$5% of yield.