• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.49 no.3
• /
• pp.216-221
• /
• 2004

Treatment effect of benzyladenopurine (BA) used to block the lateral roots formed on soybean sprouts should be influenced by its applying methods. This study was done to check the effects of temperature and period from seed imbibition into 2 ppm BA solution to the first watering for sprout culture on growth and morphology of soybean sprouts. Imbibed three cultivar (cv. Pungsannamulkong, Sowonkong and Junjery) seeds for 5 houys into 2 ppm BA solution were placed under different temperatures (AT; 20, 30, $40^{\circ}$) and periods (AP; 0, 1, 2, 3, 4 hours). On the 6th day, the soybean sprouts were classified by 4 categories on the base of hypocotyl length; ＞7cm, 4 to 7cm), ＜ 4cm and non-germination to calculate their composition rates, number of lateral roots, lengths of hypocotyl and root diameters at middle and hook of hypocotyl, and fraction dry weights were measured. Germination and growth responses of the cultivars were changed by AT and AP treatments. The responses, lateral root formation and fresh weights were, however, mainly affected by the cultivars used rather than Af treatment. Rate of the sprouts which formed lateral roots was decreased with increased periods to 4 hours, but their number per sprout was not different between the treatments of longer than 3 hours. Lengths of hypocotyl and root organ and total fresh weights were the highest in an hour AP treatment although longer than 3 hour AP treatments did not showed the significant difference in the lengths. Conclusionally AP treatment was more important than Af one in seed aeration for soybean sprout culture immediately after imbibition into BA solution, and was done at least for 3 hours.

• Ocean and Polar Research
• /
• v.27 no.1
• /
• pp.67-74
• /
• 2005

The phonology and reproductive effort of Zostera marina L. (Dongdae Bay and Aenggang Bay) on the southern coast of Korea were investigated from September 2002 to August 2003. The Dongdae Bay(DB) exhibited a finer sediment grain size with richer organic content than the Aenggang Bay(AB). Water temperature at DB site ranged from $7.5^{\circ}C$ in February to $25.5^{\circ}C$ in August, while water temperature at AB site ranged rrom $6.7^{\circ}C$ in February to $25.2^{\circ}C$ in september. Both populations exhibited a perennial lifB span, but the sexual reproductive effort was significantly higher at DB than AB. The reproductive shoots of DB site were developed from February to June 2003, while those of AB site from March to June 2003. At DB site, the frequency of reproductive shoot ranged from 11 to 33%, whereas reproductive shoot of AB did below 5%. Reproductive structures were larger and more abundant at DB, with the exception of number of fruits and seeds per spadix. Water temperature seems most important to regulate the timing of reproductive phase of Z. marina populations for two study sites.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.2
• /
• pp.109-113
• /
• 1998

In this study we tried to transform an antimicrobial peptide gene (Shiva) under the promoter of tomato phenylalanine ammonia-lyase (tPAL5) into tobacco and potato plants. Antimicrobial peptide gene was isolated originally from giant silk moth (Hyalophora cecropia) and modified ie nucleotide sequence to increase antimicrobial activity. Transgenic tobacco plants were regenerated and their seeds were tested on the media containing kanamycin (500 mg/L). The results of PCR amplification and genomic Southern blot hybridization confirmed the integration of construct (tPAL5 promoter-Shiva-NOS-GUS-NOS) into chromosome. We observed that one of the transgenic tobacco plants showed chromosome rearrangement when integrated. In case of potato transformation, the efficiency of regeneration was maximized at the medium containing Zeatin 2mg/L, NAA 0.01mg/L, GA$_3$ 0.1mg/L. We also observed the high expression of GUS (${\beta}$-glucuronidase) enzyme which was located next to the terminator sequence of nopaline synthase gene (NOS) in the vascular tissue of stem, leaves of transgenic potatoes. This result suggested that a short sequence of Shiva gene (120 bp) and NOS terminator sequence might be served as a leader sequence of transcript when translated.

• Journal of Korean Society of Forest Science
• /
• v.38 no.1
• /
• pp.33-45
• /
• 1978

The purpose of present study is to analyze the genetic variation of natural stand of Pinus densiflora. In 1975 following after the selection of 1974, twenty trees from each of three natural populations of the species were selected and their open-pollinated seeds were collected, and the locations and conditions of the populations ate presented in table 1, 2 and figure 1. Some morphological traits of the populations were already detailed in our second report of this series, in which Myong-Ju and Ul-Jin populations were regarded to be superior phenotypically to suweon population. The morphological traits of cone, seed and seed-wing, and also the growth performances and needle characters of the seedling were observed in the present study according to the previous methods. The results obtained are summarized as follows; 1. The meteorological data obtained by averaging the records of 30 year period (1931~1960) measured from the nearest meteorological stations to each population are shown in fig.2, 3, 4. The distributional patterns of investigated climate factors are generally considered to be similar among the locations. However, the precipitation density during growing season and the air temperature during dormant season on Suweon area, population 6, were quite different from those of the other areas. 2. The measurements of fresh cone weight, length, diameter and cone index, i.e., length to diameter ratio are presented in table 7. As shown in table 7, all these traits except for cone diameter seem to be highly significant in population differences and family differences within population. 3. The morphological traits of seed and seed-wing are detailed in table 8, 9, and highly significant differences are recognized among the populations and the families within population in seed-wing length, seed-wing index, seed weight, seed-length and seed index but not among the populations in the other observed traits. The values of correlation coefficient between the characters of cone and seed are given in table 10 and the positive significant correlations can be observed in the most parts of the compared traits. 4. Significant statistical differences among populations and families within population are observed in the growth performances of 1-0 and 1-1 seedling height of these progenies. But the differences in root collar diameter are shown only among families within population. As shown in table 13, the most parts of correlations are not significant statistically between the growth performances of seedling and the seed characters. 5. The number of stomata row on both sides of needle and the serration density were measured in the seedlings from each of the families of the three populations. As shown in table 15, statistical differences are considered to be significant among the populations and among the families within population in serration density but not among the populations in stomata row on both sides of the needle. The results differ from those of the third report of this series. Even if one of the reason seems to be the diversity of selected populations, it could not be confirmed definitely. The correlations between progenies and parents are not generally observed in the investigated traits of needle as shown in table 16.

• Current Research on Agriculture and Life Sciences
• /
• v.18
• /
• pp.19-25
• /
• 2000

$F_2$ populations of the crosses KC47-1 (PI244670) ${\times}$ KCB14-2-2-3-2 (PI201234), KC220-1 ${\times}$ KC268 and $F_3$ bulk populations of the crosses KC47-1${\times}$KC263 (AC2258), KC47-1${\times}$KCB13-2-1 (PI201232), KC47-1${\times}$KCB13-4-2 (PI201232), either one parent of which was resistant to Phytophthora blight, were tested for both gray leaf spot and Phytophthora blight by serial inoculation with Stemphylium solani or a mixture of S. solani and S. lycopersici, and P. capsici in 1999. In 2000, $F_3$ and $F_4$ lines or populations developed from the respective $F_2$ or $F_3$ selections in the previous year were evaluated for resistance to both diseases. A significant progress in resistance to both diseases was achieved by selection.

• KSBB Journal
• /
• v.9 no.2
• /
• pp.186-190
• /
• 1994

The content of taxol and related compounds in various tissues of native yews( T. cuspidata var. latifolia) grown in 5 locations of Ullung Island were analyzed. A considerable range of vanation in the content was observed in the needle and bark collected from different trees located at the same area as well as at five different areas. Taxol content was much higher in the needle(0.017% on the dry weight basis) than those in the bark, whereas the content of 10-deacetyl baccatin III(10-DAB III) was slightly higher in the bark(0.073%), regardless of the location of the trees collected. Particuayly, the needle collected from the Hyunpo area, which located in North-west part of Ullung Island, contained the highest level of taxol(0.024%) exceeding the reported level in dried barks of Pacific yew and also somewhat higher level of its Precusor, 10-DAB III(0.049%). These results suggested that the needle of the yew at the Ullung Island could be suitable materials as a renewable source for the mass production of taxol.

• Korean Journal of Plant Tissue Culture
• /
• v.25 no.4
• /
• pp.267-271
• /
• 1998

Cotyledon explants of lettuce were cocultured with Agrobacterium tumefaciens LBA4404::pBKS-GR1 harboring glutathione reductase(GR) gene in MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip for 48 hr. These explants were transferred to MS medium supplemented with 0.1 mg/L NAA and 1.0 mg/L 2ip, 50 mg/L kanamycin, and 500 mg/L carbenicillin. After 4 weeks of subculture, kanamycin-resistant shoots were obtained on selection medium. Leaves of putative transformants survived on selection medium containing 100 mg/L kanamycin. Incoporation of the GR gene into lettuce was confirmed by PCR analysis of genomic DNA. Southern blot analysis showed that ECL-labeled GR gene was hybridized to the expected amplified genomic DNA fragment of about 1.8 kb from transgenic lettuce. The presence of mRNA in transgenic lettuce was confirmed by RT-PCR with total RNA of transgenic lettuce. In progeny test of transformants, R$_1$ seeds were resistant to kanamycin (200mg/L) on MS medium.

• Korean Journal of Plant Resources
• /
• v.34 no.1
• /
• pp.73-78
• /
• 2021

We report a technique for obtaining seeds of 'Cheongnarae' (a variety of Hosta minor cultivated at the Korea National Arboretum in 2019) by artificial crossing of H. minor, collected from Jeju Island, as the female parent and H. minor 'Krossa Regal', cultivated outside Korea, as the male parent. Among the individuals obtained after sowing, those that showed different morphological characteristics, such as leaf shape and color, were selected. Among these individuals, those with thick leaves and light-colored flowers were further selected. Vegetative propagation and cultivation steps were repeated for evaluation of the characteristics. 'Cheongnarae' has relatively thicker leaves and a darker color (RHS 137A) than the control variety 'Black Hills' and has wings at the point where the petiole meets the leaf blade. The shape of the leaf blade edge is clearly sinuous, and the flower color is close to white (White N155B). 'Cheongnarae' cultivated in this way can be used for pot plant or gardening.

• Korean Journal of Environmental Biology
• /
• v.40 no.2
• /
• pp.206-213
• /
• 2022

Ecological characteristics of a brown alga, Scytosiphon lomentaria, were investigated from January 2021 to December 2021 in its natural habitat off Sodol, Jumunjin, eastern coast of Korea. The S. lomentaria population at the site formed widespread patches on mid shore. During the investigation, environmental conditions including seawater temperature, salinity, and dissolved oxygen were monitored at the site. Growth and maturation of the S. lomentaria population were identified through qualitative and quantitative investigations. An estimation of the effective cumulative temperature for maturation of the alga was obtained based on growth data and a biological zero temperature of 8℃. Sporangia were observed from February to May when seawater temperatures ranged from 7.7℃ to 16.4℃. A maturation peak was detected in April when seawater temperature was 12.1℃. After zoospore release, the alga became bleached and only the crust remained after June. Developmental initiation of the thallus occurred at temperatures above 8℃. Its maturation required approximately 162 degree-days.

• Korean Journal of Environment and Ecology
• /
• v.36 no.2
• /
• pp.177-201
• /
• 2022

Following the adoption of the global plant conservation strategies at the Conference of the Parties for Biodiversity Conservation, diligent actions to achieve each targets are actively carried out. In particular, the need for ecological conservation research to achieve targets 2 and 7 of GSPC-2020 has increased. The priority taxa to accomplish the objectives of GSPC-2020 are rare and endemic plants. In particular, endemic plants with limited distribution in specific regions are evaluated to face a high risk of extinction. To address the necessity to preserve endemic plants, we investigated the distribution of Prunus choreiana H. T. Im, a Korean endemic plant. After that, we examined the vegetational environment of the habitat of P. choreiana and evaluated its population structure. The productivity of its fruits and the effects of pollinators on fruit production were evaluated as well. The fruiting ratio was calculated based on the number of flowers produced. Lastly, we observed the annual growth characteristics of P. choreiana. The habitats of P. choreiana did not show a specific type of vegetation. All of them were located in a limestone area of Gangwon-do in the central Korean Peninsula and occupied a site where the coverage of the tree layer and the sub-tree layer was not high or did not exist. The population structure of P. choreiana contained a high proportion of mature plants capable of producing fruits and a low proportion of seedlings and Juvenile plants. We found that the production of fruits required pollinators and was affected by the performance of each plant. Although P. choreiana produces many flowers, only a maximum of 20% and only 2-6% on average bear fruits. These flowering characteristics may be due to pollinators' low abundance and activity during the flowering season (between mid-March and early April), suggesting that many flowers are needed to attract more pollinators. We rarely observed the re-establishment of seedlings in the population of P. choreiana. Despite that, we predict the population to persist owing to its long lifespan and periodic production of numerous fruits. However, if the tree layer and sub-tree layer in competing status with P. choreiana increase their crown density, they are expected to inhibit the growth of P. choreiana and affect the risk of its extinction. Therefore, the current changes in the vegetational environment of the habitats are expected to decrease the number and extent of P. choreiana in the long term. The results of this study may serve as primary and important data necessary for the achievement of GSPC-2020 objectives.