• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.2
• /
• pp.167-176
• /
• 1999

Shoot morphological characteristics were affected by plant population densities in alfalfa. Shoots per plant, yield per shoot, yield per plant, and stem diameter increased with decreasing alfalfa population density. Winter survival was maximized at a plant population of $45plants\;m^{-2}$ or less. The grams of TNC per root increased as the stand density decreased. The lowest LT 50 occurred at the lowest stand density ($16plants\;m^{-2}$ having 25 cm plant spacing) and the highest LT 50 was attained at the highest stand density($494plants\;m^{-2}$ having 4.5 cm plant spacing). There were no differences in shoot morphology, winter survival, and cold hardiness in between 'Algonquin'and 'Vernal'. From this study, high stand density of alfalfa ($278plants\;m^{-2}$ or more) appears to be of little advantage compared to low stand density in terms of winter survival and cold hardiness.

• Asian Journal of Turfgrass Science
• /
• v.25 no.1
• /
• pp.94-99
• /
• 2011

This study was performed to investigate the effect of foliar feeding as the fertilization on creeping benrgrass green. Research results have showed that the visual quality of bentgrass as well as shoot density and chlorophyll index dramatically improved after foliar feeding. Shoot density of bent grass in foliar based fertilization was 2.8 ea/$cm^2$ higher than that of the liquid based fertilization during the experiment period, moreover that the foliar feeding is more effective to alleviate shoot density during the rainy season in summer. Results showed that foliar feeding was key role to achieve the stable visual quality, chlorophyll index and maintained Normalized Difference Vegetation Index (NDVI) throughout the year in addition to get fast recovery after aeration and dry spot. These were consistent with the previous research of foliar feeding which directly provided nutrient to the turfgrass leaf thus increased turfgrass growth within a short time. It is projected to be a especially adequate management program during the hot summer season in which the nutrition feeding is low. However, root growth was no significant difference between foliar based fertilization and liquid based fertilization. Golf Course managers also should consider about the number of frequent fertilizing. Lastly, it was no big change in chemical property by soil foliar based fertilization which is meaning of preventing the soil salinization, meanwhile, it is prone to reach the nutrient deficiency. It hopes to be settled as the general fertilization in golf course of Korea, since there are many advantages of foliar based fertilization program. It is suggested to study more practical process of foliar feeding through the further research.

• Journal of Plant Biotechnology
• /
• v.31 no.2
• /
• pp.145-149
• /
• 2004

We investigated the anatomical aspects of vitrification in peace poplar. Comparisons were made with regard to characteristics occurring between hyperhydric and normal shoots in shoot proliferation cultures on MS medium containing 0.2 mg/L BA. Compared with normal plants, hyperhydric plants had thick, curled, and dark green leaves. Hyperhydric stems were thicker and shorter than those of normal stems. When examined under the microscopes, the mesophyll palisade cells of hyperhydric leaves were vacuolated, whereas those of normal leaves contained normal and enriched vacuole with cytoplasm. Generally, the hyperhydric leaves showed poorly developed palisade parenchyma, and revealed irregular and bigger sized intercellular structures in both palisade and spongy parenchyma as well as epidermis cells compare to those of normal leaves. In addition, the hyperhydric leaves had lower stomatal density and bigger sized cell. Vascular tissues of hyperhydic stems were less differentiated because of poorly lignified xylem tissue. The greatly expanded cortical cells and pith appeared to be the main cause of thick stems as compared with normal stems.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.25 no.4
• /
• pp.106-116
• /
• 2020

To examine distribution of the Zostera species growing naturally in Ulleungdo, scuba diving surveys using ships were conducted along the coast and inside the harbors of the island at the end of September 2019. In areas of seagrass occurrence, environmental factors such as nutrient concentrations in water column and sediment pore water, salinity, and sediment organic content were also analyzed. Zostera caulescens meadows appeared in the relatively deep waters (14-24 m MSL) of Cheonbu-ri, Jeodong-ri, Sadong-ri, and Namyang-ri in Ulleungdo, and the total seagrass coverage was approximately 4.9 ha. Approximately 0.9 ha of Zostera marina meadow was found at the depths of 3-5 m MSL within Hyeonpo-hang in Hyeonpo-ri. The average shoot density and biomass of Z. caulescens were 121.9±9.7 shoot m^-2 and 99.0±13.2 gDW m^-2, respectively, with no significant differences by location. The average shoot density and biomass of Z. marina were 193.8±18.8 shoot m^-2 and 102.6±6.8 gDW m^-2, respectively. The nutrient concentrations in the sediment pore water and sediment organic content in the seagrass meadows in Ulleungdo were lower than those in eelgrass meadows on the southern and eastern coasts of Korea. These results will provide useful basic information for the marine protected species, Z. caulescens and Z. marina, and for the conservation of the waters of Ulleungdo, which has been designated as a marine protected area.

• Journal of Korean Society of Forest Science
• /
• v.102 no.4
• /
• pp.477-483
• /
• 2013

The purpose of this study was to calculate uncertainty of emission factor collected data and to evaluate the applicability of Monte Carlo simulation technique. To estimate the distribution of emission factors (Such as Basic wood density, Biomass expansion factor, and Root-to-shoot ratio), four probability density functions (Normal, Lognormal, Gamma, and Weibull) were used. The two sample Kolmogorov-Smirnov test and cumulative density figure were used to compare the optimal probability density function. It was observed that the basic wood density showed the gamma distribution, the biomass expansion factor results the log-normal distribution, and root-shoot ratio showd the normal distribution for Pinus densiflora in the Gangwon region; the basic wood density was the normal distribution, the biomass expansion factor was the gamma distribution, and root-shoot ratio was the gamma distribution for Pinus densiflora in the central region, respectively. The uncertainty assessment of emission factor were upper 62.1%, lower -52.6% for Pinus densiflora in the Gangwon region and upper 43.9%, lower -34.5% for Pinus densiflora in the central region, respectively.

• Journal of Bio-Environment Control
• /
• v.25 no.2
• /
• pp.106-110
• /
• 2016

In this study, a planting density-growth-harvest (PGH) chart was developed to easily read the growth and harvest factors such as crop growth rate, relative growth rate, shoot fresh weight, shoot dry weight, harvesting time, marketable rate, and marketable yield of common ice plant (Mesembryanthemum crystallinum L.). The plants were grown in a nutrient film technique (NFT) system in a closed-type plant factory using fluorescent lamps with three-band radiation under a light intensity of $140{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and a photoperiod of 12 h. Growth and yield were analyzed under four planting densities ($15{\times}10cm$, $15{\times}15cm$, $15{\times}20cm$, and $15{\times}25cm$). Shoot fresh and dry weights per plant increased at a higher planting density until reached an upper limit and yield per area was also same tendency. Crop growth rate, relative growth rate and lost time were described using quadratic equation. A linear relationship between shoot dry weight and fresh weights was observed. PGH chart was constructed based on the growth data and making equations. For instance, with within row spacing (= 20 cm) and fresh weight per plant at harvest (= 100 g), we can estimate all the growth and harvest factors of common ice plant. The planting density, crop growth rate, relative growth rate, lost time, shoot dry weight per plant, harvesting time, and yield were $33plants/m^2$, $20g{\cdot}m^{-2}{\cdot}d^{-1}$, $0.27g{\cdot}g^{-1}{\cdot}d^{-1}$, 22 days, 2.5 g/plant, 26 days after transplanting, and $3.2kg{\cdot}m^{-2}$, respectively. With this chart, we could easily obtain the growth factors such as planting density, crop growth rate, relative growth rate, lost time and the harvest factors such as shoot fresh and dry weights, harvesting time, marketable rate, and marketable yield with at least two parameters, for instance, planting distance and one of harvest factors of plant. PGH charts will be useful tools to estimate the growth and yield of crops and to practical design of a closed-type plant production system.

• Weed & Turfgrass Science
• /
• v.7 no.2
• /
• pp.140-147
• /
• 2018

In Korea, mowing the grass of a grave (Beolcho) is a very important event preceded by Chuseok (Korean thanks giving day) and Si-Hyang (annual ancestral feast). Because Beolcho usually takes place one or two weeks before Chuseok, the traffic accidents on roads are getting worse and safety accidents are getting more and more. Erroneous Beolcho methods can cause the soil to be exposed and cause the loss of soil or the low shoot density of graveyard grass or weed occurrence. Therefore, the dispersion of the Beolcho timing and the approprite method can be import issues. The present study assessed the effects of grass mowing timing and height before Chuseok on the growth of Zoysia japonica and Z. matrella. The mowing timing was evaluated at 1 week, 2 weeks, 3 weeks, and 4 weeks before Chuseok, and the mowing height differently according to the two type of grass. In Z. japonica, the faster mowing before Chuseok, the longer the plant height, and the coverage rate and shoot density were higher. In Z. matrella, the faster mowing, the longer the shoot length, but the coverage rate and shoot density did not show any difference or tendency. As compared to Z. japonica, the plant height of Z. matrella was kept short regardless of the time of mowing. In both grasses, the plant height was shortened when mowing was done at low cutting height, but the coverage rate and shoot density were decreased. In addition, it was shown that it is advantageous to maintain the shoot density of graveyard lawn by 40-50 mm or 30-40 mm cutting above the ground for Z. japonica or Z. matrella, respectively.

• Korean Journal of Medicinal Crop Science
• /
• v.28 no.2
• /
• pp.136-141
• /
• 2020

Background: The leaves of the goji berry (Lycium chinense Mill.) are used as raw materials in processing and by replace fruits to some extent. The reason is that the leaves are cheaper, however, betaine content is higher than in the fruits. These experiments were conducted to determine the planting density and cutting height for producing a large number of leaves. Methods and Results: The cultivar 'Myeongan' with many branches was used. When the shoot height reached 50 cm - 70 cm, harvesting was possible four times a year. The time to next harvest was approximately 38 days after regeneration of new shoots. Leaf quantity was in the order of 1st > 2nd > 4th > 3rd harvest. Insect damage occurred during the third harvest in late July and early August, therefore, eco-friendly control was necessary. The total yield was higher at the planting density 60 cm × 30 cm than that of 60 cm × 20 cm or 60 cm × 40 cm. The yield at cutting for shoot height of 60 cm was increased by 6.3 percent compared to that of 50 cm, At the cutting height of 70 cm, harvest was difficult owing to hardening of stems and thorns. Betaine content, an indicator component of goji berry, was not significantly different according to planting densities and cutting height. Conclusions: The ideal cutting period to produce leaves of goji berry for processing is when the shoots grow to approximately 60 cm, and the leaves can be harvested 4 times a year. The dried-leaf yield was highest at the planting density of 60 cm × 30 cm.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.14 no.1
• /
• pp.41-47
• /
• 2009

Since significant losses of seagrass coverage have been reported from many parts of the world, numerous restoration projects through seagrass transplantation have been attempted worldwide. Different survival rates and establishment time of transplants have been reported depending on transplanting time and methods. The staple method, which is direct seagrass planting method using staples to anchor seagrass transplants on the sediments, have been widely adopted in seagrass transplanting because this method achieves high survival rates in various sediment environments. To assess the morphological plasticity and the growth characteristics of transplants, we transplanted eelgrass, Zostera marina in December 2004 using the staple method. Shoot density, morphological characteristics and leaf productivities of the transplanted shoots and shoots of natural eelgrass beds in the vicinity of the transplanting site and environmental parameters in the planting site were monitored for about 1 year postplanting monthly. Transplant shoot density increased without initial decline, while leaf width and sheath length of transplants decreased after transplanting. Leaf productivities per shoot of transplants also considerably lower than those of natural shoots for the first 3 months post-transplanting. Shoot density, morphological characteristics and leaf productivity per area of transplants became similar to those of natural population about 1 year after transplanting. Although eelgrass transplants might have experienced some transplanting stress during the early stage of the transplantation, transplants appeared to adapt well to new environments of the transplanting site.

• Korean Journal of Environmental Agriculture
• /
• v.37 no.2
• /
• pp.87-96
• /
• 2018

BACKGROUND: The vigorous shoot growth in upper part of apple tree canopy leads to poor fruit quality and flower bud formation in lower part of canopy. So, this study was conducted to develop the proper control method about the shoot growth in upper part of apple tree canopy. METHODS AND RESULTS: Trunks of 'Fuji'/M9 apple trees were cut (back pruned) to 2.5 m in tree height on 11 February (dormant) or 12 April (full bloom). Naphthalene acetic acid (NAA) was applied at 2.0% to cut surface when trunk was pruned. Prohexadione-calcium (Pro-Ca) was sprayed at 250 mg/L above 2.0 m in tree height at 23 April (petal fall). The NAA or Pro-Ca application after trunk was pruned at dormant (TR-2 and TR-3) significantly reduced shoot growth in upper part of canopy compared with the control (tree was only pruned at dormant, TR-1), but the percent of shoots showing the secondary growth of TR-3 was higher over 2 times than that of TR-2. The reduction of shoot growth in upper part of canopy by TR-2 and TR-3 increased the fruit red color from the lower part in the treating year and blooming of the lower part in the following year. CONCLUSION: Applying 2.0% NAA to cut surface of pruned apple trunk at dormant was the most effective way for stabilization of the tree vigor in upper part of the canopy in a high density apple orchard.