• Journal of Korean Society of Forest Science
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• v.77 no.2
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• pp.193-198
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• 1988

This study was carried out to investigate the influence of shading pretreatment and planting density on the periodic needle leaves growth in fresh and dry weight. 1. The fresh and dry weight growth of needle leaves per seedlings increased with light intensity and decreased with increase of density. The best growth of needle leaves in fresh weight and dry weight appeared during the period from May to June. 2. The contribution rates to the growth of fresh and dry weight of needle leaves were 1.9% and 5.1% in light intensity, 3.6% and 3.2% in density and 83.7% and 75.6% in growth period, respectively. 3. For the three factors, shading, density and growth period, all the interactions between any two factors, and among the three factors in the fresh and dry weight growth of leaves per plant were significant.

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.93-98
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• 1990

Interspecific competition between E. colona and rice was determined over four growth stages in replacement series. No competition between the two species as measured by plant height, leaf area and dry weight occurred by 30 days after seeding (DAS) at all the density combinations studied. At 45 DAS reductions in leaf area and dry weight of E. colons due to the competition occurred at the density combinations where number of competing E. colons plant was less than that of rice. However, there was a great increase in leaf area and dry weight of E. colons at the density combination of one E. colons competing with four rice plants at 60 DAS. As the number of E. colons plants increased, the leaf area and dry weight of E. colona decreased resulting from intraspecific competition between E. colons plants. Although rice absorbed more nitrogen than E. colons up to 30 DAS, the reverse was observed from 45 DAS. A relatively small amount of phosphorous was absorbed by both rice and E. colons, but the amount of phosphorous taken up by E. colons was greater than that taken up by rice. E. colons absorbed extremely high amount of potassium when compared to rice.

• Research in Plant Disease
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• v.14 no.3
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• pp.153-158
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• 2008

This study was conducted to develop a easy seedling method to test large amounts of barley and wheat cultivars for resistance of powdery mildew. In addition, we also examined the resistance of genetic resources that have been used in barley and wheat breeding programs in Korea. This seedling test used paper bag with seeds can be completed within three weeks. to-day seedlings were available to inoculation and 8 days was needed for result reading. This method can test at least 180 collections at one time. we can identify the two resistant types by leave symptoms showed non infection and necrotic spots. Among the 79 Korean barley cultivars, only two cultivar, 'Sangrokbori' and 'Dajinbori' were resistant and 'Jejubori' showed moderate resistant. There was no resistant in hulless barley and wheat cultivars. It was same results in comparison of earlier resistant reports in field test. We confirm that this method could using in test of powdery mildew resistance in barley and wheat. Among the 1,401 genetic resources using in Korean breeding program, malting barley has more resistant collections comparing to 796 hulled and hulless barley and 273 wheat germplasms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.4
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• pp.439-444
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• 1983

Effects of temperature and soil moisture on the growth and grain-filling of two wheat cultivars were investigated. Two levels of temperature; day 3$0^{\circ}C$/night $25^{\circ}C$ and day 2$0^{\circ}C$/night 15$^{\circ}C$ and two levels of soil moisture; stressed (45-50% of F.C.) and non-5tressed (50-60% of F.C.) were imposed in the green house from heading date to the maturity and grain weight, chlorophyll content of flag leaf and leaf area index(LAI) were observed at weekly interval. Grain maturation was faster in the high temperature than those in the lower temperature. Chlorophyll content of flag leaf and LAI decreased rapidly in the high temperature and chlorophylls disappeared at the 20 days after heading. In lower temperature condition, slower decrements were shown in chlorophyll content and it remained until 45 days after heading. Grain weights in the high and optimum temperature conditions reached to maximum values at 29 days and 45 days after heading, respectively. Differences of grain weight and chlorophyll content of flag leaf were not significant between stressed and non-5tressed soil moisture condition.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.1
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• pp.93-100
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• 1985

Five winter and five spring wheat cultivars of diverse genetic backgrounds were evaluated to examine different developmental responses in terms of stages of the life cycle and grain yield when grown under the different planting dates. Greatest difference in growth and developmental patterns of the winter and spring wheat cultivars occurred in stem elongation, booting, inflorescence emergence and anthesis. The growth stage of stem elongation was found to exhibit larger difference both among planting dates and cultivars. Winter wheat cultivars responded more than spring wheat cultivars to the different planting dates. Winter wheat 'Cho Kwang' and spring wheat 'Jugoku 81' were earlier and exhibited faster growth and development, while winter wheats 'Yamhill' and 'Hyslop' were later in growth and development, but exhibited faster grain filling and higher rate of grain filling, resulting in higher grain yields. Crosses between winter and spring wheat gene pools would result in earlier maturity and higher productivity for both winter and spring wheat cultivars. For developing early maturing wheat cultivars for multiple cropping sequences while maintaining productivity, selection for earliness trait should be started at the stem elongation stage. Furthermore, the breeding materials should be planted at several times for selection of shorter life cycle genotypes adaptable to the cropping sequences. This is due to the genotype x planting date interactions.

• Journal of Korean Society of Forest Science
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• v.80 no.2
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• pp.202-209
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• 1991

This study was carried out to examine seed germination, seedling growth, and biomass production of Eucommia ulmoides. The results were summarized as follows ; 1. Cold moist stratification at a refrigerator showed 60.3% of seed germination, which is the most effective among pretreatment methods. 2. In case of 1-0 seedlings, sixty seedlings per $1m^2$ was the most appropriate density, and the growth quality of seedlings differed significantly among densities. 3. Height growth showed continuous growth pattern and the maximum growth was shown during the period 21 June to 20 July, which corresponds 32.7% of total annual growth. 4. As tree age and DBH increased, the production of bark and leaf increased, however, its increment rate remarkably dropped down after ten years. 5. When tree age was ten years, the rate of bark volume showed the maximum value, 12.42%. 6. Dry weight of barks and leaves and bark volume were positively related to the growth of DBH and height. 7. As tree age increased, leaf area decreased, but the number of leaves increased.

• Korean Journal of Environment and Ecology
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• v.21 no.5
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• pp.400-414
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• 2007

This study has analyzed the vegetation structure to suggest a vegetation ecological restoration model by using the case of the afforestation for erosion control area with Pinus koreaiensis and Betula platyphylla, etc., on the hills of the Young-in mountains after its great fire in 2000. Of the area having a dimension of $1,152,404.3m^2$ selected as a survey site for the existing vegetation, the forest fire area accounted for 69.2% among which, brushwoods accounted the most for 24.67%. As a result of analysis of the 27 surveyed unit plots[unit dimension: $100m^2$] set up in consideration of the existing vegetation pattern and damaged state from the forest fire, the surveyed area was classified into 10 communities. Shrub layer's vegetation was found to be dominant in forest fire areas and the surveyed sites were classified into 5 plant communities, i.e. P. koraiensis community, Quercus variabilis community, P. thunbergii community, Q. serrata community, B. platyphylla community in forest fire areas, while non-forest fire areas were classified into 5 plant communities, such as P. densiflora community, Q. acutissima community, Q. serrata community, Q. mongolica-Q. serrata community, B. platyphylla community. Species diversity of forest fire areas was $0.3679{\sim}0.5907$ and that of non-forest fire areas was $0.5728{\sim}0.8865$. In addition, the number of the species in the forest fire areas was $5{\sim}8$ and that of non-forest areas was $8{\sim}12$; however, the population of forest fire areas$(156{\sim}456)$ was higher than that of non-forest fire areas$(61{\sim}227)$. In the analysis of growth density per layer$[of\;100m^2]$, there appeared $1{\sim}8$ trees of Q. mongolica and $3{\sim}5$ trees of Q. serrata in the upper layer species; $2{\sim}4$ trees of Q. serrata and one tree of Q. mongolica in the canopy layer. As for the characteristics of soil, acidity of forest fire areas was pH 5.45 and that of non-forest fire was pH 5.25. By setting up the middle D.B.H range of Q. mongolica-Q. serrata community as the vegetation restoration model, planting species, planting density and planting models are suggested.

• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.143-150
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• 1989

This research was performed to estimate the influence of relative light intensity and planting density on the growth of dry weight of needles and other organs growth in Korean white pine seedlings raised in the transplanting bed. 1. As treated with various light intensities, relationships between needle dry weight and growth of other organs(dry weight of shoot, root and diameter of seedlings) had significantly positive correlations and linear regressions, but regression between needle dry weight and seedling elongation was a second degree polynomial. As treated with various planting densities, the second degree regression curve was found between needle dry weight and shoot dry weight, and seedling elongation, And linear regression between needle dry weight and root dry weight, and seedling dry weight could be estimated, while any regression between needle dry weight and diameter was not recognized. 2. As treated with various light intensities, linear regression between leaf area and shoot dry weight, and seedling dry weight, exponential regression between leaf area and seedling elongation were significantly recognized, while a tendency of logarithmic regression between leaf area and diameter appeared. According to the different density treatment, logarithmic regression between leaf area and shoot dry weight, linear regression between leaf area and root dry weight, and seedling dry weight, but quadric regression between leaf area and seedling elongation and diameter were significantly found.

• Journal of the Korean Wood Science and Technology
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• v.44 no.3
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• pp.323-336
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• 2016

This study was carried out to evaluate the physicochemical properties of steam exploded wood chips for peat moss substitute in vegetation media. Also, the mixtures at the different ratios of peat moss and pretreated wood chips (90 : 10, 70 : 30 and 50 : 50 (w/w), respectively) were evaluated by physicochemical and plant growth characteristics. The pretreated wood chips was showed that bulk density, porosity and pH were $0.26g/cm^3$, 93.3% and 5.7, respectively. This result indicates that physicochemical properties was improved when wood chips was apply to steam explosion in the range of optimum physicochemical condition for vegetation media. In particular, the mixture ratio of peat moss and pretreated wood chips to 70 : 30 (w/w) showed higher seed germination, plant height and leaf growth than peat moss. Also, the bulk density, porosity, water holding capacity, pH and C/N ratio were $0.20g/cm^3$, 91.8%, 76.1%, 5.2 and 51.0 in the range of optimum physicochemical condition for vegetation media.

• Korean Journal of Soil Science and Fertilizer
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• v.24 no.1
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• pp.55-60
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• 1991

This study was carried out to obtain the effects of soil environment and characteristics on the growth and yield of young rice seedling. Twenty four rice fields were selected among the labor saving mechanization complex, and the growth statu s and various soil characteristics were investigated The young rice seedling planted soils were located at the range of elevation 5m to 210m, and the average water holding days was 5.1 days, and drainage class were mainly moderately well to imperfectly. The plant height on 30th day after machine transplanting were higher and the tiller numbers were smaller at the higher clay contents at moderately well and imperfectly drained soils. In case of sandy loam soils, the better the drainage class, the higher plant and more tillers. Soil hardness was lower in sandy loam, and the bulk densities of loam, silty clay loam and poorly drained soils were lower than the other fields. There were not differences of soil chemical properties between the soil textural groups but organic matter content were higher in poorly drained soils. The rice yields of young seedling planted fields were negatively correlated to soil bulk density and highly significantly correlated to the exchangeable calcium contents of the soils. The average yield of young rice seedlings was 487kg/10a, 2.5% higher than semi-adult rice seedling of 475kg/10a.