• Journal of Bio-Environment Control
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• v.25 no.4
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• pp.294-301
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• 2016

This study was conducted to analyze the seedling quality of korean melon and the growth after transplanting of korean melon nursed under the LED sources. LED sources were RB7 (Red:Blue=14:2), RB3 (Red:Blue=12:4) and Blue(B=16). Photosynthetic photon flux density(PPFD) was 50, 100 and $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The lighting treatment was started after graft-taken and was applied for 20 days at 4 hours(05:30 and 07:30, 17:30 and 19:30) per day. Plant height and stem diameter of scion were longer and thicker under a high ratio of blue light condition. Dry matter ratio and compactness were highest in RB3 compared to the other LED sources treatments. $CO_2$ exchange rate increased $5.44{\mu}molCO_2{\cdot}m^{-2}{\cdot}s^{-1}$ under RB7 $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ and dropped to negative values under control. PPFD $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of RB3 resulted in the longest plant height by 132.3cm and flowering ratio also was the highest by 75%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.4
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• pp.376-385
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• 1984

The habit of anthesis and maturity of sesame were investigated as a basic research for the improvement of high-yielding varieties and cultural practices. Eight different plant types were identified using typical cultivars among gene pool grown in Korea. Non-branching, Monocapsule, Bicarpels quadriloculi (NMB) type showed higher ratio for capsule setting compared with Non-branching, Monocapsule, Quadricarpels octoloculi (NMQ) type. Non-branching, Tricapsules, Quadricarpels octoloculi(NTQ) type presented lower ratio for capsule setting than non-branching, tricapsules, bicarpels quadriloculi(NTB) type. The number of flowers by flower setting position was the highest on lower part, intermediate on middle part, and the lowest on higher part in NMB and NTB type. However, the number of flowers was the highest on middle part, intermediate on lower part, and lowest on higher part in NMQ and NTQ type. BMB type appeared to have the highest ratio for capsule setting when compared with the other plant types. BTB type with many flowers and capsules exhibited higher percentage for capsule setting than BTQ type with lowest capsule setting percentage. Capsule setting percentage of branch appeared to be lower than that of main stern in the branching type. The branching type had more flowers and capsules than non-branching type. Tricapsules type had more flowers and capsules per plant than monocapsule type, and bicarpels quadriloculi type had more than quadricarpels octoloculi type. However, capsule setting ratio in non-branching type was higher than in branching type. The ratio was higher in monocapsule type than in tricapsules type. Bicarpels quadriloculi type had higher ratio of capsule setting than quadricapels octoloculi type. Number of capsules per plant and capsule setting ratio are supposed to be dominated by shape of capsule (number of carpels and loculi), not by branching or number of capsules per axil. The order of number of capsules per plant was as follows; BTB, BMB, NTB, BTQ, BMQ, NTQ, NMQ, and NMB types. However, the order of capsule setting ratio was as follows: BMB, NMB, NTB, NTQ, NMQ, BMQ, BTB, BTQ types. Consequently, branching, tricapsules, bicarpels quadriloculi(BTB) type was considered as a sourse of breeding for high yielding varieties by introducing the genes govering BMB type with one capsule per axil which has high capsule setting ability.

• Journal of Plant Biology
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• v.17 no.1
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• pp.15-21
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• 1974

The most commonly grown economical and flue-cured tobacco cultivar Yellow Special A was used in pot-culture tests in order to study Ethrel (2-chloroethyl phosponic acid) effects on accelerating maturity of tobacco leaves in relation to the most adequate level of the chemical useful for field growing, nitrogen level in soil for the most pronounced response, and the most suitable spray period during the growth stages of pre-, post- and topping periods. The following conclusions, thus, were obtained from the present studies; 1. 500ppm Ethrel spray was reconfirmed to be adequate in the practical applications, although the extent of yellow-ripening of tobacco leaves was increased as the Ethrel level increased. The highest leevel treated resulted in causing chemically damaged lesions on leaves and early defoliation. 2. Ethrel-treated leaves showed deeper yellowish tinge to them than those without treatment, while different levels of the chemcial had less influence on the tinge. 3. An adequate level of nitrogen supply to plants favored the Ethrel response, whereas either very low or high level of nitrogen in the soil lowered the chemical effect on accelerating the yellow-ripening. When carbohydrates versus total nitrogen ratio became relatively high, the condition brought out some outstanding Ethrel effects. 4. Chlorophyll level of leaves increased as soil applications of nitrogen level increased, and that also increased carotenoid level of the tobacco leaves. Ethrel-treated leaves showed deeper orange tinge than those without treatment, while the highest level of nitrogen application showed the deepest orange tinge to tobacco leaves. 5. Pre-topping treatment (12 days before topping and flowering) resulted in almost no Ethrel response, and that treatment right on the day of topping, showed response of yellow-leaf ripening at nearly bottom-half leaves of a tobacco plant. The post-topping treatment (12 days after topping) made plants showing full response of Ethrel from bottom to the top leaves of tobacco plant in accelerating the leaf maturity. 6. The extent of Ethrel responses on accelerating yellow-ripening of tobacco leaves was discussed for the modifying influences brought about by certain environmental factors. Discussions were also made about the possible practical applications (particularly for pre-rice planting) and quality difference that may be caused by such growth environments.

• Journal of the Korean Institute of Landscape Architecture
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• v.19 no.3
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• pp.1-15
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• 1991

The current status of evergreen ground-cover plants as of in the winter months in 50 places selected at random in Seoul was assessed to see how they are at the present, and the following matters of evergreen ground-cover plants were observed to be common aspect of them today during the year of 1989 and 1990 and in winter of Seoul. 1. Ground-cover area in 50 different places of Seoul was 36% of the green area, and the evergreen ground-cover area was 3% of total ground-cover area. As the result, most of ground cover plants founded to be zoysia grasses. 2. Total number of evergreen ground-cover plants species was 24, and the species most frequently found were Juniperus chinensis and horizontalis, Buxus koreana, Liriope platyphylla var. nana. Taxus cuspidats, Rhododendron lateritium, Pleioblastus pygmaea, Poa pratensis in that order of the number of plasces assessed, and sere Poa pratensis, Agrostis tennuis, Liriope platyphylla, Buxus koreana, Juniperus chinensis and horizontalis, Taxus cuspidata. var. nana, Rhododendron lateritium in the order of area planted. 3. Woody plants included 9 species and occupied 16% in the area, also introduced plants included 14 species and occupied 79% in the area. As introduced evergreen grasses occupied, almost of evergreen ground-cover herbs, planting of evergreen ground-cover herbs and native plants are thought to be desirable. 4. Flowering plants of 16 species were found to be 16% of the total evergreen ground-cover area. 5. The ratio of topographical difference, such as plain versus slope for planting site, was 82 and 18% respectively, and sunny versus shady and intermediate places were 72, 15 and 13% respectively. 6. Although appearance of plants was generally fair, poor and drying plants were assessed 33% for the number of places planted, and 11% for the area. It seems to be necessary to manage those plants to their growth characteristics, and desiable to introduce various plant species adaptable to the winter climate of Seoul and grow for the winter landscaping purpose. 7. The poor use and lack of evergreen ground-cover plants are regarded to be deficient in the valus and reconization of them, particularly in the landscaping works. It is therefore considered important to bring out pertinent measures against these inadequate situations.

• Journal of People, Plants, and Environment
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• v.24 no.5
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• pp.485-498
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• 2021

Background and objective: This study was conducted to find out the status of plant utilization in the current textbooks by analyzing the plants by grade and subject in the national textbooks for all elementary school grades in the 2015 revised curriculum in Korea. Methods: The data collected was analyzed using Microsoft Office Excel to obtain the frequency and ratio of collected plant data and SPSS for Windows 26.0 to determine learning content areas by grade and the R program was used to visualize the learning content areas. Results: A total of 232 species of plants were presented 1,047 times in the national textbooks. Based on an analysis of the plants presented by grade, the species that continued to increase in the lower grades tended to decrease in the fifth and sixth grades, the upper grades of elementary school. As for the number and frequency of plant species by subject, Korean Language had the highest number and frequency of plant species. The types of presentation of plants in textbooks were mainly text, followed by illustrations and photos of plants, which were largely used in first grade textbooks. In addition, as for the area of learning contents in which plants are used, in the lower grades, plants were used in the linguistic domain, and in the upper grades, in the botanical and environmental domains of the natural sciences. Herbaceous plants were presented more than woody plants, and according to an analysis of the plants based on the classification of crops, horticultural crops were presented the most, followed by food crops. Out of horticultural crops, flowering plants were found the most diversity with 63 species, but the plants that appeared most frequently were fruit trees that are commonly encountered in real life. Conclusion: As a result of this study, various plant species were included in elementary school textbooks, but most of them were horticultural crops encountered in real life depending on their use. Nevertheless, plant species with high frequency have continued a similar trend of frequency from the previous curriculums. Therefore, in the next curriculum, plant learning materials should be reflected according to social changes and students' preference for plants.

• The Korean Journal of Ecology
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• v.14 no.2
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• pp.211-230
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• 1991

The germinatin of e. annuus continued from the middle ofmay to mid-october. The maximum germination occurred on the mid-july. The period bloom of was distingushed amongs the different growth forms ; a orm pr of biennial and a form of pr perennial flowering from the mid-may to mid-september, and a form ps biennial blossom from the beginning of October to earlynovember. the dispersal of seed for(a form pr)occurred from early June to the mid-september. A rotte, germinating from summer to autumn, could classified into several growth forms; individuals without a critical leaf area for bolting until september and October, become a form ps of biennial, whicth did not proceed toreproductive growth unitl the next year, even thought wintering. individuals flowered on 3 years after germination become a form pr of perennial. The growth formular of aform pr of bennial, grown in a pot was w=20.2[1+$3.36{\times}10^3$(-0.062t)]$^{-1}$. The maximum relative growth rate(rgr) was 0.062g/g/day and the maximum net assimlation rate(nar) 0.089g/g/day. Therelative growth among each organ was shown as R=0.12 $T^{1.15}$between the avove-ground part(t) and the below- ground part(r). the relation between the avove-ground part(t) and the ratio of stem weight(wi) was ws/wi=2.56 $T^{0.35}$. n.p.k. was largely distributed on a leaf throughoutthe total growth period. while growing, it tended to decrease on the vegetative organ gut vice versa on the reproductive organ. however, nitrogen was more widely distributed on a leaf then in the reproductive organ.

• Korean Journal of Plant Resources
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• v.27 no.6
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• pp.701-706
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• 2014

Three highbush blueberries (Vaccinium corymbosum cvs. Bluecrop, Coville, and Northland) grown in an open field and in a rain shelter were compared to evaluate the potential benefits of rain-sheltering systems on growth and fruit quality. Shrubs grown in rain shelter flowered 5-14 days earlier and were in full bloom earlier than those in the open field. All three cultivars set fruit by nearly 90% of flowers when they were grown in the open field, but was markedly reduced when they were grown in the rain shelter, to approximately 50% for 'Bluecrop' and 'Coville'. Fruit sets ratio of 'Northland' grown in the in the rain shelter was 14.5. Fruit from greenhouse-grown 'Northland' were larger, heavier, and had more seeds per berry. Soluble sugar content (SSC) of fruits varied both with the cultivars and growing conditions. SSC of fruits grown in the greenhouse was higher in 'Bluecrop' compared to that grown in the field, but this pattern was reversed in 'Northland'. Titratable acid was significantly higher in fruits from rain shelter-grown shrubs of both 'Bluecrop' and 'Northland' than in fruits from open field-grown shrubs (P < 0.05), although there was no difference in TA with respect to growing conditions for 'Coville'. The number of seed per fruit, fruit length and diameter, weight, SSC, and TA were similar in 'Coville' shrubs grown in the open field and the rain shelter. Fruit firmness of 'Bluecrop', 'Coville', and 'Northland' was higher in the rain shelter than in the open field. 'Coville' and 'Northland' fruits harvested in the open field had higher blue chroma than those harvested in the rain shelter. However, this pattern was reversed for 'Bluecrop'. On the whole, sheltering from rain affected most fruit characteristics of the three cultivars differently. Therefore, suitable blueberry cultivars for the rain shelter should be chosen by purpose.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.189-189
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• 2017

Salinity is one of the major abiotic stresses that severely affect crop production throughout the world; especially rice plant which is generally categorized as a typical glycophyte as it cannot grow in the presence of salinity. Phenotypic resistance of salinity is expressed as the ability to survive and grow in a salinity condition. Salinity resistance has, at least implicitly, been treated as a single trait. Physiological studies of rice suggest that a range of characteristics (such as low shoot sodium concentration, compartmentation of salt in older rather than younger leaves, high potassium concentration, high $K^+/Na^+$ ratio, high biomass and plant vigour) would increase the ability of the plant to cope with salinity. Criteria for evaluating and screening salinity tolerance in crop plants vary depending on the level and duration of salt stress and the plant developmental stage. Plant growth responses to salinity vary with plant life cycle; critical stages sensitive to salinity are germination, seedling establishment and flowering. We have established a standard protocol to evaluate large rice germplasms for overall performance based on specific physiological traits for salt tolerance at seedling stage. This protocol will help in identifying germplasms which can perform better in the presence of different salinity treatments based on single trait and also combination of different physiological traits. The salt tolerant germplasm can be taken forward into developing better varieties by conventional breeding and exploring genes for salt tolerance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.134-142
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• 2017

Crop production in rice paddy fields is of great importance because of declining rice consumption and the low self-sufficiency ratio for field crops in Korea. A controlled drainage system (CDS) is recognized as an effective means to adjust water table (WT) levels as needed and control soil water content to improve the soil environment for optimum crop growth. The present study evaluated the effects of a CDS on soil characteristics, including soil water distribution and soybean development in paddy fields. The CDS was installed with two drain spacing (3 m and 6 m) at the experimental paddy field at the National Institute of Crop Science, Miryang, Korea. It was managed with two WT levels (0.3 m and 0.6 m) during the growing season. Soil water content, electrical conductivity and plant available nitrogen content in the soil were significantly greater in the 0.3 m WT management plots than in the 0.6 m plot and the control. At the vegetative stage, chlorophyll content was significantly lower with higher WT control because of excess soil moisture, but it recovered after the flowering stage. Soybean yield increased with WT management and the 0.6 m WT treatment produced the greatest grain yield, $3.38ton\;ha^{-1}$, which was 50% greater than that of the control. The CDS directly influenced outflow through the drains, which significantly delayed nutrient loss. The results of this study indicated that WT management by CDS can influence soil characteristics and it is an important practice for high yielding soybean production in paddy fields, which should be considered the crop growth stages for stable crop production.

• Journal of Crop Science and Biotechnology
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• v.10 no.4
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• pp.249-256
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• 2007

A study was conducted to observe the variation and inheritance of agronomic traits and their interrelationship in mungbean. The objective of the study was to compare agronomic traits and hardseed percentage of 268 recombinant inbred lines(RILs) developed from the cross between wild Vigna subspecies sublobata "ACC 41" with the mungbean cultivar "Berken". The RIL population and their parents were evaluated under controlled conditions in a glass house at the University of Queensland, Brisbane, Australia. The results showed significant differences among the RILs and among the parents in all traits under study. Berken had a longer flowering date and a higher seed weight per plant, but less total leaf number and pod number per plant than ACC 41. A germination test between papers revealed that ACC 41 was 100% hard-seeded and did not germinate at all, while Berken germinated up to 100%. Their RILs distributed well between 0 to 100% hardseed. Upon scarification, all hardseed germinated within seven days. Narrowsense heritability estimates of total leave number, hardseedness, pod length, and pod width were highly heritable at 89.9, 98.9, 93.7, and 93.2%, respectively. The heritability of seed weight per plant and number of seeds per plant were lower at 63.1 and 58.4%, respectively. Seed weight per plant showed positive transgressive segregation when compared with ACC 41 and a positive correlation with 100 seed weight. While the number of seeds per pod showed a negative transgressive segregation when compared with Berken and a negative correlation with pod length and pod width. The RILs gave a 1:1 segregation ratio in leaflet shape, growth habit, and growth pattern, indicating that these traits were controlled by a single dominant gene.