• Journal of Ecology and Environment
• /
• v.41 no.9
• /
• pp.256-264
• /
• 2017

Background: The aim of this study was to clarify the relationship between the sexual reproduction and the resource allocation in a natural Polygonatum humile population grown in a temperate mixed forest gap. For this aim, the plant size, the node which flower was formed, the fruiting rate, and the dry weight of each organ were monitored from June 2014 to August 2015. Results: Firstly, in 3-13-leaf plants, plants with leaves ${\leq}8$ did not have flowers and in plants with over 9 leaves the flowering rate increased with the number of leaves. Among plants with the same number of leaves, the total leaf area and dry weight of flowering plants were larger than those of non-flowering plants. The minimum leaf area and dry weight of flowering plants were $100cm^2$ and 200 mg, respectively. Secondary, the flowers were formed at the 3rd~8th nodes, and the flowering rate was highest at the 5th node. Thirdly, cumulative values of leaf properties from the last leaf (the top leaf on a stem) to the same leaf rank were greater in a plant with a reproductive organ than in a plant without a reproductive organ. Fourthly, fruit set was 6.1% and faithful fruit was 2.6% of total flowers. Biomasses of new rhizomes produced per milligram dry weight of leaf were $0.397{\pm}190mg$ in plants that set fruit and $0.520{\pm}0.263mg$ in plants that did not, and the difference between the 2 plant groups was significant at the 0.1% level. Conclusions: P. humile showed that the 1st flower formed on the 3rd node from the shoot's base. And P. humile showed the minimum plant size needed in fruiting, and fruiting restricted the growth of new rhizomes. However, the fruiting rate was very low. Thus, it was thought that the low fruiting rate caused more energy to invest in the rhizomes, leading to a longer rhizome. A longer rhizome was thought to be more advantageous than a short one to avoid the shading.

• Korean Journal of Medicinal Crop Science
• /
• v.1 no.2
• /
• pp.184-190
• /
• 1993

This study was carried out to investigate the appropriate medium and constitutionof growth regulators for somatic embryogenesis for development of rapid mass propagation system via somatic embrygenesis in Rehmennia glutinosa. Embryogenic callus formation from leaf explant was more effective when 4mg / l BA with 0.5mg / l NAA than that of treated with only auxins or cytokinins. LS medium was suitable for embryogenic callus formation. LS medium with 4mg / l BA with 0.5mg / l NAA was effective for the maintenance and proliferation of embryogenic callus. In suspension culture, addition of 1mg / l BA to LS medium was proper for somatic embryogenesis. The highest rate of shoot developement form cotyledon stage embryo was obtained in 1/2 LS medium and plantlet survived by 75% after transplanted to the soil. after 4 weeks.

• Journal of Plant Biotechnology
• /
• v.44 no.1
• /
• pp.49-55
• /
• 2017

We investigated the callus induction and plant regeneration ability of 16 maize genotypes, including the Korean inbred lines, using 9 to 15 day-old immature zygotic embryos from maize grown in pots and from field cultures. Immature zygotic embryos placed on MS medium supplemented with L-proline 0.7 g/L, MES 0.5 g/L, Dicamba 1.5 mg/L, 2,4-D 0.5 mg/L, $AgNO_3$ 4 mg/L, and sucrose 20 g/L, showed the highest frequency of callus induction. The highest number of shoots regenerated when the embryogenic callus were transferred to MS medium supplemented with 5 mg/L zeatin. The root formation was observed when shoots were grown on MS medium supplemented with 0.2 mg/L indole-3-butyric acid (IBA). Additionally, under the same culture conditions, immature zygotic embryos from maize grown in the field also had a high frequency of plant regeneration. Except one genotype, 15 genotypes showed callus induction and shoot regeneration. Among the 16 genotypes tested, H99, B98, HW3, and B73 yielded the best plant regeneration. H99 showed maximum shoot formation from the primary embryogenic callus. The results suggest that genotypes and growth conditions of the maize plant plays very important roles for enhancing the embryogenesis competence of immature zygotic embryos. The successful regeneration from immature zygotic embryos of maize inbred lines provides a basis for molecular breeding of new cultivars by genetic transformation.

• Journal of Sericultural and Entomological Science
• /
• v.31 no.1
• /
• pp.1-11
• /
• 1989

To investigate changes of dry weight, C/N ratio, carbohydrate, ratein and nucleic acids in the barks of the hardwood cutting of mulberry plants, the barks of the hardwood cutting were taken every 10days from the cutting day to 40days after cutting. Results were summarized as follows : Growth of shoot and root in Keomseolppong (Morus bimbycis KoIDZ.) after cutting was better than that in kaeryangppon (Morus alba L.) and Daeryugppong(Morus Lhou(SER.) KoIDZ.). Dry weight in the barks of the hardwood cutting decreased up to 40days after cutting (decrease percentage of dry weight : about 14%) and Keomiseolppong showed the highest decrease precentage of dry weight. Change of C/N ratio decreased in the initiation, whereas that from 10days after cutting increased with the growth of new shoot, C/N ratio was the highest in Keomseolppong and the lowest in Kaeryangppong. Total sugar showed decreasing tendency up to 40 days after cutting the increase from 10 days to 20 days. Reducing sugar increased in the frist 20days, followed gradually decrease up to 40 days after cutting Starch levels decreased up to 40 days. Change in the content of starch closely paralleled to that of dry weight of bark of the hardwood cutting. Content of total sugar and starch in Keomseolppong was the highest, and was consumed more than that in the rest of varieties. Crude protein and soluble protein increased up to 10 days after cutting, followed decrease up to 40 days. Protein content of Keomseolppong was smaller than that in the rest of varieties. RNA content showed the same tendency with that of protein content, but Keomseolppong showed always the highest. Content of DNA did not show any change and difference among three varieties.

• Korean Journal of Plant Resources
• /
• v.24 no.5
• /
• pp.628-635
• /
• 2011

This study was conducted to establish the tissue culture system for Korean domestic Miscanthus sinensis, which is used in various purposes such as forage, and bio-energy resources. With the mature seed of Miscanthus, optimum concentrations of plant growth regulators were identified for an efficient callus induction and regeneration. Among the treatments of 1~10 $mg{\cdot}L^{-1}$ 2,4-D, IBA, or NAA, callus induction rate was highest (85.3%) on MS medium containing 5 $mg{\cdot}L^{-1}$ 2,4-D. Under the condition, the callus were efficiently induced and proliferated with comparably lower frequencies of callus browning. In shoot regeneration, the treatment of NAA combined with BAP seemed to contribute more efficient conditions to shoot regeneration than those of NAA with Kinetin or 2-iP. Especially, regeneration efficiency and number of regenerated plants were 83.7% and 5.5 in 3 $mg{\cdot}L^{-1}$ NAA with 5 $mg{\cdot}L^{-1}$ BAP, respectively, which were higher frequencies than those in NAA with Kinetin or 2-iP. In results, 5 $mg{\cdot}L^{-1}$ 2,4-D and 3 $mg{\cdot}L^{-1}$ NAA combined with 5 $mg{\cdot}L^{-1}$ BAP were efficient for embryogenic callus induction and regeneration of Miscanthus. This system would be useful for mass-propagation and developing new cultivars via tissue culture of Miscanthus sinensis.

• Journal of Plant Biotechnology
• /
• v.35 no.1
• /
• pp.63-68
• /
• 2008

Single-node stem pieces ca. 1 cm in length containing a axillary bud were obtained from in vitro plants of potato (Solanum tuberosum L.). The influences by a position of the node and the existence of a leaf at the node were observed in the single-node culture on the 8% sucrose MS medium. The effect of CCC was also investigated for the microtuberization. The apical part node was excellent in the tuberization not to mention shoot length, fresh weight, diameter, the number of node on the in vitro culture of a single-node than the lower part. The differences in the diameter of a tuber formed in the part of the axillary bud on all treatments including the cultivation of the apical part node were not recognized. However, the fresh weight of the tuber showed high value in the tuber formed at the axillary bud of shoot apex part. At 20 days after cultivation, tuberization was promoted in the new stolen that developed from the bud of node with a leaf under SD condition of 8 hours at $20^{\circ}C$. The tuberization from axillary bud of the single-node without leaf was inhibited at high temperature of $28^{\circ}C$ regardless of daylength. Whereas, tuberization at $20^{\circ}C$ and $28^{\circ}C$ was similar without the difference under SD condition but the tuber formation ratio were low. CCC 500 mg/L promoted tuberization and the effect was also showed even under LD condition at $28^{\circ}C$. The inhibiton of tuberization under LD and high temperature condition could be solved by treatment with CCC.

• Journal of Korean Society of Forest Science
• /
• v.96 no.3
• /
• pp.295-299
• /
• 2007

Resistance to chestnut gall wasp (Dryocosmus kuriphilus) of Korean prevailing chestnut cultivars, new cultivars released by Korea Forest Research Institute (KFRI), and local cultivars by growers was investigated to select optimal cultivars suitable for main chestnut producing areas. During three years investigated from 2004 to 2006, we could find no damage by chestnut gall wasp in any cultivars of test sites located in Gongju and Chungju of the central area. However, most cultivars of Gwangyang, Sancheong and Hapcheon sites located in the southern area showed a lot of damage by chestnut gall wasp. Hapcheon was most severe in comparison with regional damage by chestnut gall wasp. From comparison among cultivars, Kwangeun, Sandae, Eunsan and Idae released by KFRI showed no damage suggesting the highest resistant cultivars. On the contrary, over 20% in total damage by chestnut gall wasp was investigated in Tanzawa, Riheiguri, Kurakata-amaguri, Pyeonggi, Gwangdeok, Seil, Sinipyeong and Yumabyuni suggesting susceptible cultivars. In damage by chestnut gall wasp according to investigated position within tree, weak shoot was more severe than bearing shoot. Damage by chestnut gall wasp of major cultivars in Gwangyang, Sancheong and Hapcheon sites was remarkably decreased in 2006, and it seems to be caused by biological control by natural enemies such as Torymus sinensis.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.33 no.6
• /
• pp.501-507
• /
• 2000

Distribution and habitat characteristics of Zostera (Zosteraceae) in the eastern coast of Korea were examined along with plant monohology, sediment composition and physicochemical factors of seawater from June 1998 to July 2000, The results showed that three species, Zostera marina, Z. asiatica and Z, caespitosa were found in specific habitats. The depth of habitat for Z. asiatica was deeper ($8.5{\~}15.0 m$) than that of Z. marina ($1.3{\~}5.6 m$) and Z. caespitosa ($3.2{\~}5.2 m$). Z. marina beds were observed at brackish-water, port and inner bay with the sediment type of sand or muddy sand. Habitats of Z. asiatica were restricted to the open bay with the sediment type of sand, Zostera have been described with regard to different growth forms of vegetation, flowering shoot and life history. Vegetation and flowering shoot length varied significantly with habitats; values ranged $66.8{\~}110.0 cm$ and $128.0{\~}217,8 cm$, respectively. Morphology of Z. marina varied with water depth and different substrates. Morphological characteristics of Z. asiatica showed a new phenotype at the deeper water depth. Vegetation and flowering shoots of Z. caespitosa were not significantly different between study sites (values ranged from 64.9 cm to 70.3 cm). Nutrient concentrations of seawater were higher at southern part than at middle part of the eastern coast of Korea. Distribution of Zostera in the eastern coast of Korea was dependent upon differences in water depth and habitat environments, by which affected the morphological differences were affected.

• Korean Journal of Medicinal Crop Science
• /
• v.6 no.4
• /
• pp.294-298
• /
• 1998

The factors affecting direct somatic embryogenesis from different parts of explant in liquid culture of Scrophularia buergeriana were investigated. Direct somatic embryogenesis was dependent on the explant tissues and stem was the most efficient explant. Rapid shoot development occurred on stem after 3-week culture but roots were not developed yet. Plantlets were not formed through somatic embryogenesis after 3-week culture of petiole. Though direct somatic embryo was not observed from leaf segment culture for 3 weeks, normal plantlets were developed after 8-week culture. BA played the main role for somatic embryogenesis in liquid culture and adding of either IAA or NAA caused rather adverse effects. Culture of stem segments in MS liquid medium with BA at 0.5 mg/ l or 0.1 mg/ l was proved to be the most efficient method for producing plantlets through direct somatic embryos.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.1
• /
• pp.104-110
• /
• 2015

In order to develop new Kalopanax pictus shoot Jangajji (KJ) with low salt concentration, physicochemical changes of KJ soaked at different concentration of soybean sauce (10~50%) were investigated for 50 days. The pH of KJ increased significantly with increasing concentration of soybean sauce in soaking solution (P<0.05). Titratable acidity and NaCl concentration of all KJ increased during storage for 50 days at $10^{\circ}C$. The total bacterial count slowly increased during early storage time and reached its highest level (4.74 log CFU/g) after storage for 30 days. KJ-20 (KJ added with 20% soy sauce) showed the highest scores for taste, flavor, texture, and overall acceptability. The total polyphenol and flavonoid contents of KJ extract increased with increasing concentration of soybean sauce. DPPH and ABTS radical scavenging activities of KJ extract were 27.22% and 38.37% (control), 40.74% and 43.65% (KJ-10), 41.79% and 50.37% (KJ-20), 43.09% and 52.60% (KJ-30), 48.62% and 53.45% (KJ-40), and 50.85% and 60.79% (KJ-50), respectively.