• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.306-318
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• 1995

To investigate the effect of low light intensities and the inoculation of Frankia and/or Alpova diplophloeus on the symbioses development and their host growth, red alder(Alnus rubra Bong.) seedlings were grown in an air - filtered walk - in growth chamber with either $N_2$ - fixing Frankia inoculation or N - fertilization and live or dead spore inoculation of the ectomycorrhizal fungus A. diplophloeus(Zeller & Dodge) Trappe & Smith. When they were 20 weeks old, the seedlings were grown under three levels of light intensities of 680, 320 and $220{\mu}mol/m^2/s$ PPFD(photosynthetic photon flux density) for three weeks. PPFD of 220 significantly decreased the development of A. diplophloeus mycorrhizae and nodules, the rates of $N_2$ - fixation and $CO_2$ exchange, and the growth of tile seedlings. PPFD 320 significantly decreased the $CO_2$ exchange rate only. Frankia inoculation significantly increased mycorrhiza formation and seedling growth. Alpova inoculation significantly increased seedling growth but not nodule development and $N_2$ - fixation. None of the symbionts affected $CO_2$ exchange rates. Frankia was more critical for seedling growth and mycorrhizal development than the mycorrhizal fungus for seedling growth and nodule development.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.1
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• pp.7-12
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• 1977

This experiment was conducted in the laboratory in order to find out the relationships between the root growth and soil physical properties. The soils selected for this study were Sangju sandy loam, Yeongog loam, Hwadong silty clay loam, which have been considered to be a typical upland soils of Korea. Artificial core samples were made with various moisture contents and bulk densities. Elongation rate of pea seedling taproot and soil strength were measured respectively in these core samples. The results obtained are summarized as follows: 1. The soil strength increased with the bulk density and deceased with moisture content. 2. The correlation between root elongation and soil bulk density was significantly recognized at the same moisture content and the root elongation was influenced by the bulk density more significantly at dry condition. 3. The elongation rate of pea seedling taproot was significantly decreased by increasing the strength (Yamanaka tester and Fine probe) of the soils. 4. The soil strength of $21kg/cm^2$ in fine metal probe or 24mm in Yamanaka tester was considered to be the critical point for plant growth, which was restricting root elongation smaller than 1/4 of the maximum growth rate.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.307-316
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• 2007

Yellow poplar (Liriodendron tulipifera L.) has low germination rate relatively other species, so the seedling production of Yellow poplar is a hard task. Accordingly this study was conducted to determine the optimal germination conditions for healthy seedling production and to promote survival rate after afforestation. Gemination percentage was examined at different media and seed covering materials using planting flats in the greenhouse. The best germination percentage was observed in sand for media and compound soil for covering materials. But it was time to transplant, seedlings became a poor character (i.e. height, root length, number of root, dry weight) in sand for media. In order to produce healthy seedlings, each different medium was compounded with TKS-2 (this is a gardening bed soil.) in the ratio 1:1 (v/v.), and compared two conditions. Quality of seedling was better than not mixed TKS-2 into each medium. Transplanting seedlings from greenhouse to nursery grew up rapidly 2 months later (early in August~early in October). Growth amount during two months corresponded to 85.6% and 71.3% in total growth amount of height and diameter at root collar, respectively. In the case of the competition-density effect on yellow-poplar seedlings, direct seedling produced the maximum 35 standard seedlings above 8 mm of root collar diameter per $m^2$, while transplanting seedling produced the maximum 64 standard seedlings per $m^2$. And produced seedlings of two way were significantly different rootlet while axial root and lateral root was not significantly different.

• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.55-56
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• 1999

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.414-420
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• 1988

This research was performed to estimate the degree of influence of relative light intensity and planting density on the weight growth in the trans-planting bed. The Piuns koraionsis seedlings treated for different degrees of shading on seed bed were planted in transplanting bed. 1. The seedling weight growth under 100% relative light intensity and $6{\times}6$ plot(36 individual) density showed the largest growth and the best growth was found during 26th of May 25 of June. 2. As the relative light intensity decrease and with planting density increased, the weight growth decreased. And the weight growth had a tendency to decrease after 26th of May-25th of June. 3. T/R ratio showed the highest value under 63% relative light intensity and $12{\times}12$ plot (224 individual) of planting density. The highest T/R ratio was found during 26th of July-25th August.

• The Plant Pathology Journal
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• v.27 no.2
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• pp.110-115
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• 2011

Aggressiveness was studied in seven Plasmopara halstedii (sunflower downy mildew) pathotypes: 100, 300, 304, 314, 704, 710 and 714. Aggressiveness criteria including percentage infection, latent period, sporulation density and reduction of hypocotyl length (dwarfing) were analysed in one sunflower inbred line showing a high level of quantitative resistance. Genetic relationships were detected between the seven pathotypes using 12 EST-derived markers. Pathotypes 100, 300, 304 and 314 were characterized with shorter latent period and higher sporulation density than pathotypes 710, 704 and 714. All pathotypes showed high percentage infection values and caused a large reduction in seedling size except for pathotype 314 involved in dwarfing. Pathotypes 714, 704 and 314 had an intermediary genetic position between the pathotypes 100 and 710. No correlation was detected between aggressiveness traits and EST genotypes.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.374-384
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• 2022

There is an increasing demand for Tetradium daniellii seedlings due to their uses as alternative energy, for ecological restoration, and as a honey plant. This study was conducted to determine the optimum container for superior seedling production of T. daniellii. Experiments were performed using five plastic container types (500, 350, 320, 300, and 250 ml) for forestry facility cultivation. The height and root collar diameter growth of T. daniellii seedlings were significantly high in the 350-ml container. High growth appeared primarily in the container with a larger cavity volume and lower growing density. Root development was most active in full sunlight. The maximum dry matter production was observed in the 350-ml container, which was similar to the results of height and root collar diameter growth. QI, an index showing the quality of a seedling, was maximum at 0.97 in the 350-ml container. In conclusion, the 350-ml container is optimum for superior seedling production of T. daniellii.

• Journal of Environmental Science International
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• v.27 no.10
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• pp.821-829
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• 2018

This study was conducted to examine the influence of Light-Emitting Diode (LED) light quality in urban agricultural plant factories on the growth and development of Seolhyang strawberry daughter plants in order to improve the efficiency of daughter plant growth and urban agriculture. LED light quality by demonstrated that above-ground growth and development were greatest for daughter plant 2. Daughter plant 1 showed the next highest growth and development, followed by daughter plant 3. Among the different qualities of LED light, the stem was thickest and growth rate of leaves was highest for R + B III (LED quality: red 660 nm + blue 450 nm/photosynthetic photon flux density (PPFD): $241-243{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and lowest for R (red $660nm/115-117{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). Plant height, leaf width, petiole length, and the leaf growth rate were highest for W (white fluorescent lamp/$241-243{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and lowest for R + B I (red 660nm+blue 450nm/$80-82{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). For above-ground growth and development, as the plants surpassed the seedling age, mixed light (red + blue), rather than monochromatic light (red or blue), and higher PPFD values tended to increase development. Regarding the quality of the LED light, daughter plant 2 showed the highest chlorophyll content, followed by daughter plant 1, and daughter plant 3 showed the least chlorophyll content. When the wavelength was monochromatic, chlorophyll content increased, compared to that when PPFD values were increased. Mixed light vitality was highest in daughter plant 2, followed by 1, and 3, showed increased photosynthesis when PPFD values were high with mixed light, in contrast to the results observed for chlorophyll content.

• Journal of Bio-Environment Control
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• v.25 no.2
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• pp.100-105
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• 2016

In this study we investigated the suitability of horticultural main organic root substrate materials (peatmoss, coir) for the development proper root substrate for working with bulb onion transplanter. We investigated seedling sprout ratio, growth and characteristics (bulk density, root substrate cohesion) those are suitable for mechanical transplanting by mixing with inorganic materials(red clay etc.). Although both seedling growth and root substrate bulk density were similar in peatmoss and coir based root substrates, we found that peatmoss mixing had higher root substrate cohesion compared to coir mixing. We assume that higher cohesion properties of peatmoss based root substrate will give more weight of root part during mechanical transplanting of young onion seedlings in the field. Because of this, we suggest that peatmoss is the appropriate ingredient for developing root substrates for working with bulb onion transplanter.

• Journal of Forest and Environmental Science
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• v.34 no.1
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• pp.1-11
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• 2018

We studied natural and plantation forest ecosystem of Sarguja in Chhattisgarh, India in order to understand how vegetation biomass, carbon stock and its allocation patterns vary among the sites. For this, stratified random sampling was opted to measure the different layers of vegetation. Wide floral diversity was found in the natural forest site as compared to the teak stand. Overall, 17 tree species found in natural forest comprising 8 families while in the teak stand 6 species were recorded. In understory strata 23 species were recorded (18 herbs and 5 shrubs) in natural forest whereas in teak stand 20 herb species and 3 shrubs were found. Great variation was also seen in the population dynamics of the different vegetation stratum in concerned sites. The sapling, seedling and herb density was found to be highest in natural stand while tree and shrub density was more in teak stand. Results indicated that stand biomass of the natural site was $321.19t\;ha^{-1}$ while in the teak stand it was $276.61t\;ha^{-1}$. The total biomass of tree layer in plantation site was $245.22t\;ha^{-1}$ and natural forest $241.44t\;ha^{-1}$. The sapling, seedling, shrub and forest floor biomass was found highest under natural forest as compared to the teak plantation site. Carbon stock has similar trend as that of biomass accumulation in natural forest and teak stand. Higher biomass accumulation and carbon stock were recorded in the higher girth class gradation of the population structure. Proper efforts are required to manage these diverse ecosystems to obtain higher biomass and sustainable ecological services.