• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.1
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• pp.15-20
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• 2001

Plant growth regulators were treated on the cut perennial ryegrass (Lolium perenne L. cv. Reveille) to investigate the effect on the regrowth after cutting. The growth showed better result when 0.1 or 0.5 mg/L cytokinin were treated. Among cytokinins, kinetin or 2iP gave the better effect on the growth than BAP. In 2.4-D as an auxin. cut plants grew best at the concentration of 0.1 mg/L. The initial regrowth was very vigorous when GA$_3$ was treated as a growth regulator, but the growth was retarded after 2 weeks later of cutting. Co-treatment of kinetin as a cytokinin and 2,4-D as an auxin showed synergistic effect on the regrowth of cut perennial ryegrass. Both plant growth regulators gave the same result at the same concentrations in the suspension culture of perennial ryegrass cells.

• Korean Journal of Plant Resources
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• v.19 no.5
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• pp.573-579
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• 2006

This experiment was conducted to investigate growth and flowering characteristics of Celosia argentea native to Korea treated by pinching and growth retardants, diniconazole, hexaconazole and daminozide. The more increased from one to three times of pinching, the more decreased in plant height and internode length but increased number of spadix and lateral branch. Spray application of diniconazole $50mg{\cdot}L^{-1}$ and daminozide $6,800mg{\cdot}L^{-1}$ decreased plant height, internode length and leaflength, but increased number of spadix, number of leaves and number of lateral branch.

• Journal of Forest and Environmental Science
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• v.8 no.1
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• pp.35-49
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• 1992

Three theoretical growth equations, i.e., the Mitscherlich, the Gompertz, and the Logistic equation, were applied to the radical stem growth of 50 jack pines (Pinus banksiana Lamb.). For the determination of the parameters in these equations, NELDER-MEAD's method was used, which is one of the direct-search methods of optimization. It has been known to be very convenient in dealing with the issues related to optimization, specifically where the number of parameters are less than 6. It was found that although all the equations did not appropriately work as expected, the Mitscherlich equation revealed the least discrapancy from the obsered value among three. Using these equations and the first certain period data, i. e., 35, 55, 75 years, the predection of radius of age 95 was investigated. Comparing to the observed value, the most valid equation was the Mitscherlich, and the next were the Gompertz and the Logistic, in order.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.220-225
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• 1986

This study was conducted to know the effects of temperature and gibberellic acid on the dormancy block-ing of ginseng seeds at different embryo growth stage. Optimum temperature for embryo growth appeared to be I soc at the beginning stage of post ripening (up to dehiscent time), 1$0^{\circ}C$ at middle stage (for 30 days after dehiscence) and 5$^{\circ}C$ at last stage (between 30 and 92 days after dehiscence). And optimum temperature for dehiscence is about 17$^{\circ}C$, also the optimum temperature for dehiscence is higher than that of embryo growth. Germination of ginseng seed with full grown embryo was accelerated at high temperature (25-3$0^{\circ}C$). Germina-tion percentage was 80% at 105th date after dehiscence under 5$^{\circ}C$, 28% at 147th date under 1$0^{\circ}C$, but no germination under the over 15$^{\circ}C$. Gibberellic acid increased the dehiscent rate, whereas the gibberellic acid treatment may not be substituted for effect of low temperature on the germination. Low temperature may be reguired to finish the embryo growth in thickness.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.1
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• pp.36-43
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• 2023

To establish a culture system with enhanced cellular nutrition, we investigated the effects of light quality (blue, 450 nm; yellow, 590 nm; and red, 630 nm) of a light-emitting diode (LED) on the biochemical composition of Tetraselmis suecica and T. tetrathele. The protein content of both species was higher (42-69%) than the content of other biochemical substances under all wavelengths. Carbohydrate, protein, and lipid contents were higher under the yellow wavelength, which showed a low growth rate, than those under other wavelengths. The contents of all biochemical substances were low under the red wavelength, which showed a high growth rate. These results indicated that protein synthesis occurs in response to decreased cell division rate, while lipid and carbohydrate synthesis occurs owing to altered chemical composition and enzymatic activity. Therefore, we suggested a two-phase LED culture system, which emitted red LED during the early-middle exponential phase and yellow LED during the late exponential and stationary phases, to increase the yield of useful biochemical substances of T. suecica and T. tetrathele.

• Journal of Korean Society of Forest Science
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• v.113 no.3
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• pp.319-326
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• 2024

We evaluated the impact of temperature and salinity on the germination of true mangrove Sonneratia caseolaris (L.) Engl. seeds to determine the optimal conditions for their growth. Seeds were collected from Nam Dinh Province, Vietnam. The seeds underwent temperature treatments (19℃, 24℃, 30℃, and 38℃) and salinity treatments (0‰, 10‰, 20‰, 25‰, 30‰, 35‰, and 40‰). The analysis of germination characteristics and radicle growth indicated that, under the 30℃ condition, the germination rate was 88%, and the radicle growth was 25.24 mm, showing significantly higher germination rates GR), mean germination time (MGT), and germination performance index (GPI) than under other temperature conditions (P<0.05). In the 10‰ salinity treatment group, both the germination rate (88%) and radicle growth (39 mm) were significantly higher (P<0.05). High temperatures and salinity were not suitable for seed germination, and they significantly affected seed germination and early growth.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.3
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• pp.213-218
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• 1993

An experiment was carried out to investigate the effects of plant growth regulators on the growth and fiber yield of ramie. Gibberellin (GA) and Atonic acid were applied at the various levels of application dates, application frequencies and concentration. Stem growth of ramie increased greatly by applying GA on the meristem of shoot apex. Among three treatments of application frequencies of GA, that is, one time application at the stage of stem length with 50cm, twice applications at the stem length of 50cm and 100cm, and three times applications at stem length of 50cm, 100cm and 150cm, stem growth increased more as application frequency increased. GA application is more effective on stem growth at the later stage of growth than the earlier growth stage. GA treatment of 100 to 300 ppm is more effective on stem elongation than 50 ppm, which was due on the elongation of internodes without increase in number of nodes. One time application of GA enhanced leaf growth more or less regardless of concentration, but GA was applied more frequently, leaf growth was inhibited more at higher concentration. Fiber yield was the highest at the treatment of three times application of GA with 100 ppm. This treatment also showed the highest percentage of fiber with 5.3%, which is much higher value compared with that of control treatment with 4.6%. Atonic acid was less effective on stem elongation than GA, but it also seemed to be effective on the enhancement of fiber development.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.359-367
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• 2010

The objective of this study was to find optimal planting season of the effect of vegetation competition around planting tree. This study evaluates the possibility of extending the planting period of containerized seedling of Pinus densiflora (1-0 year). We planted seedling at three different seasons (spring, summer, fall) at 18 plots in 3 locations. Planting sites were composed of vigorous vegetation (Site A) and less vigorous vegetation (Site B). For over 3 years, the study investigated survival rate, growth of root collar diameter and height, and biomass of containerized seedling of P. densiflora. In all sites, containerized seedling of P. densiflora showed high survival rate in summer planting. Height and root collar diameter of containerized seedling of P. densiflora were the highest in summer planting, but in the initial period after planting growth was not good. After time passed, growth rate was increased. Site B showed better growth than Site A. Biomass was the highest in summer planting and also the highest in Site B. These results suggest that planting period can be extended by using containerized seedling and vegetation control in the initial is very important for survival and growth of containerized seedling.

• Journal of Korea Foresty Energy
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• v.23 no.2
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• pp.9-20
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• 2004

Growth and nutrients of Xinjiang poplar (Populus alba var. pyramidalis) seedlings treated with fertilizers and soil amendments were examined in nursery and windbreak at Dengkou after 6 months of treatments in Inner Mongolia, China. Soil water content was $10\%$ higher than that at most soils in desert. Height and diameter growth and foliar nitrogen (N) concentration were higher at N and nitrogen plus phosphorus (N+P) fertilizer treatments than other treatments. However, there were no differences in foliar P concentration among treatments in windbreak and foliar P concentration was higher at control than at other treatments in nursery. Yuho treatment increased height and diameter growth. Nitrogen appeared an influenciug factor for early growth of Xinjiang poplar, and P had a minor affect on growth. More long-time studies were needed to elucidate the effects of fertilizers and soil amendments on growth and nutrients of Xinjiang poplar.

• Journal of Korean Society of Forest Science
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• v.112 no.3
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• pp.290-302
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• 2023

The aim of this study was to examine the changes in the initial tree growth characteristics of Q. variabilis planted in forest fire-damaged areas treated with soil moisturizers such as biochar and to identify the factors that affect tree growth. To evaluate the effectiveness of soil moisture treatment in the area planted with QV, an experimental plot was created according to the treatment method (spread and mix) and treatment ratio (0, 4, and 40 t/ha). The survival rate of QV was 20% higher in the treatment plot than in the control plot. The height and root collar diameter (RCD)growths of QV were high on the northern slope with spread treatment and on the southern slope with mix treatment. The relative growth rate (RGR) according to the soil moisturizer treatment method was higher in the mix treatment, showing a significant difference in RCD. The northern slope had a higher RGR and significant growth rate. This suggests that the growth improvement effect may depend on the soil moisturizer treatment method. The aspect or treatment method affectsthe drying conditions of the soil, which in turn affects its moisture content or nutrient dynamics. The present research results can be used to establish soil moisturizer treatment standards that are suitable for growth purposes. In addition, this study demonstrates that biochar treatment can be considered as an effective alternative to boost biomass and facilitate early restoration of forest fire-damaged areas.