• The Journal of Natural Sciences
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• v.8 no.2
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• pp.159-168
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• 1996

The major morphological characteristics of 97 lines selected from 1,510 local collection lines of Paeonia spp. were studied and classified into some groups according to their Q correlation. The Coefficient of Variation of 8 characteristics in 97 lines varied greatly with the range from 21.3% to 127.1%. The 22 lines with useful morphological characteristics selected from 97 lines had 2n=10 chromosomes, in which there were no difference among the number of chromosomes of 22 lines. The 97 lines were classified into 14 groups based upon the results of Q correlation analysis obtained from data with 16 quantitative factors; Group III and group VI were divided into two sub-groups. Group I was large flowered lines with a single flower, Group IIIa, doubled flowered lines, Group VII, late maturing lines and Group IX, early maturing lines flowering in 17th May. Group VIII were dwarf type lines which has the shortest stem length and leaf length among 14 groups, which are suitable for potted plants. Group XIII had a lot of stems per plant and a large type leaf with leaf length and width. A needle-type leaf was found in Group X, whereas a wide and oval-type leaf in group XII.

• Korean Journal of Agricultural Science
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• v.1 no.1
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• pp.27-33
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• 1974

This experiment was carried out to determine the adequate amount of nitrogen for densely and lately seeded soybean, and the results obtained are as follows; 1) Various fertilization amounts of nitrogen did not effect the date of emergency, but the flowering and the maturing dates were delayed at the plots fertilized the nitrogen heavily. 2) In accordance with an increasing amount of nitrogen fertilization, the length of the stem and the internode was s gnificantly enlongated but the stem diameter was thinned down, and the latter was suggested to be the cause of lodging. 3) The 1,000 grain weight and the number of pods per hill were decreased according to the increasing the amount of nitrogen fertilization. 4) A highly significant difference in grain yield was recognized between varieties but among treatments. However, in case ot the extremly late cultivation, the grain yield of the early maturing variety (Choongbukbaek) was increased at the plot of 6 kg nitrogen.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.149-153
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• 1998

This experiment was carried out to obtain a basic information for new variety development. The local soybean (Glycine max. L) lines used were endowed from Chungnam Agricultural Research and Extension Services. These lines were planted at upland farm of Chungnam Nat'l Univ., College of Agri. after treatment with mutagen $\gamma$-ray. All characteristics measured were decreased due to the $\gamma$-ray treatment than check except the branches of main stem of the Hannam and plant height of the Sobak. Especially the Sobak and the Eunha among these lines were shown very sensitivly than others treated with $\gamma$-ray of 15Krad. Of characteristics surveyed the nodes per plant was very sensitive to $\gamma$-ray, while the grain weight per plant, the pods per plant and the branches per plant were gradually decreased to further radioactivity about $\gamma$-ray treatment. In the Pungsan and the Sobak lines there were not shown significant between major characteristics at treatments including check. Other lines were also not shown positive correlation among characteristics except between stem diameter and branches(0.64*), grain weight and plant height(0.77**) at check of the Eunha, between stem nodes and stem diameter(0.65*) at check of the Kwangan and between number of pods and stem diameter(0.70*) at check of the Danyeop. From result this experiment, some of lines used were to be appeared characters of interest, for example, such as the short stem and the early flowering. Therefore these lines were needed more advanced generations for stability and performance.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.171-176
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• 2010

Vicia angustifolia L. is native plant of winter annual leguminous weed in Korea. Objective of this research was to investigate the effects of V. angustifolia as green manure for rice production in sustainable agriculture. Seed size of V. angustifolia was smaller than that hairy vetch as control plant, while seed number in same amount was approximately 1.4-fold higher. V. angustifolia started stem elongation in early April. In addition, flowering and dead-ripe stages of the plant reached at May $5^{th}$ and June $1^{st}$, respectively. Growth of V. angustifolia-barley mixed cropping system in upland was promoted up to 101 cm of plant length compared to 46.6 to 60.9 cm that grown in paddy. Biomass yield of V. angustifolia was 14.5 kg $ha^{-1}$ in single cropping system of paddy soil, and the amount of nitrogen was 65 kg $ha^{-1}$. Moreover, self-reseedling of fallen seed from V. angustifolia grown in previous year in paddy soil was significantly higher than that hairy vetch plant. These results suggested that V. angustifolia can be uses as green manure in addition to reducing the mineral fertilizer application in rice production for sustainable agriculture.

• Korean journal of applied entomology
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• v.40 no.3
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• pp.211-217
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• 2001

Field survey for Orius spp., predacious natural enemies of thrips pests, on several plants by beating or sweeping method revealed that O. sauteri, O. strigicollis, O. minutus, and O. nagaii habituated in open fields or in greenhouses of Korea. Among them, O. sauteri was the most dominant species at all areas (83.0~92.5%), followed by O. strigicollis and O. minutus. Especially, O. sauteri exclusively dominated on the economically important crops such as soybean, red pepper, and watermelon. On the other hand, O. strigicallis and O. nagaii occurred mainly on ornamental plants including chrysanthemum and rose and on rice, respectively, during summer-autumn season. The seasonal occurrence varied depending on the plant. Initial population of Orius spp. was first observed on white clover in late May, followed by on soybean, red pepper, an buck wheat in early June, indcating that movement of Orius spp. relates to the flowering time of the plant. Peak of Orius spp. abundance was found first in July and secondly in August or September. On white clover and buck wheat the first peak of abundance was one week earlier than on soybean and red pepper. Therefore, we suppose that wild plants such as white clover can serve as a reservoir for Orius spp. after overwintering.

• Weed & Turfgrass Science
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• v.5 no.3
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• pp.111-125
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• 2016

Cordgrass (Spartina spp.) is recognized as a highly invasive plant in estuaries throughout the world because of remarkable versatility and resiliency, significant reproduction, strong adaptability, rapid spreading, and vigorous growth. In this review, therefore, to provide insights on the effective management practices, the previous research works were summarized and discussed. Spartina spp. is a perennial halophyte, warm-season (C4) grass that reproduces both sexually through seeds and asexually by rhizomes. Management strategies for cordgrass have included various physical, biological, and chemical controls. Herbicides are usually the most cost-effective means of control. Currently, glyphosate, imazapyr, fluazifop and haloxyfop have been practically used. To improve the control efficacy, a combination of two more than methods (example, mowing-spraying) is needed to be applied consistently every year for at least 3 to 4 years and to be sprayed with enough dry time (>4-6 hr) at an early growth stage (before flowering). Consistently repeated application of same herbicide have to be avoided to prevent an unexpected emergence of herbicide-resistant lines. On the other hand, Spartina spp. have many positive functions for agricultural and eco-engineering purposes. Thus, we have to give more intensive research for effectively managing advantages and disadvantages of Spartina plantations.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.2
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• pp.70-77
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• 2003

From March 1998 to August 2000, the phenological and morphometric changes of Zostera marina L. were examined at the Duksan Port in the eastern coast of Korea. Morphometric characteristics, phenological stage, shoot density, biomass of Z. marina population and environmental parameters were also measured. Nutrient levels in water column varied over the season. Morphometric characteristics of vegetative shoot changed with season; shoot heights ranged from 54.2 cm (March) to 100.0 cm (October). Reproductive shoots appeared from mid-March to early September of which the height was ranged from 97.8 cm (March) to 213.0 cm (July). The flowering phase started at 12$^{\circ}C$ and the fruit development was resulted up to 21$^{\circ}C$. The seed maturing was developed at 22$^{\circ}C$-$25^{\circ}C$. Shoot density and biomass in permanent quadrate (0.25 m$^2$) were significantly different among seasons ranging from 38 to 136 shoots (mean 80.3$\pm$6.5) for shoot density, and 190 g dry wt m$^{-2}$ in October 1998 to 922 g dry wt m$^{-2}$ in June 1998 for biomass respectively. Relationships between shoot morphometrics and physico-chemical parameters were not significantly correlated. Seasonal changes in water temperature seemed responsible for the replacement of reproductive phases and the annual changes of shoot morphometrics in Z. marina populations.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.789-795
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• 2015

The new garden chrysanthemum (Dendranthema grandiflorum Ramat.) cultivar 'Nuri Ball' was developed at Yesan Chrysanthemum Experiment Station of Chungcheongnam-do Agricultural Research and Extension Services in 2011. 'Nuri Ball' was bred through a cross between the '02-145-01' line as the female parent with yellow flower color and '02-04-32' as the male plant with white flower color in 2004. Three years of adaptation trials were conducted from 2006 to 2009 under natural conditions. This study compared the external shape type with that of 'White Miri' and conducted ploidy and RAPD (Random amplified polymorphic DNA) marker analyses. These tests showed that 'Nuri Ball' cultivar has its own characteristics compared with the control 'White Miri'. 'Nuri Ball' was a shrub type variety with semi-double flowers of 4.0 cm in width with white petals. It could produce 1025.2 flowers per plant in autumn. Compared with the control 'White Miri', 'Nuri Ball' was similar in terms of shape and color of flowers, but was different in flower size and number. The natural flowering time of 'Nuri Ball' was late September. It had very vigorous growth and an early budding plant. 'Nuri Ball' was demonstrated to be a new cultivar based on ploidy test and RAPD analysis. 'Nuri Ball' is intended for use as a bed chrysanthemum and expected to contribute to farm incomes in landscaping.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.591-594
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• 2011

A new poinsettia(Euphorbia pulcherrima. Willd. ex Klotzch) cultivar 'Red Stone' was bred by the National Institute of Horticultural and Herbal Science (NIHHS) in 2009. In 2006, a cross was made between 'Freedom Rose', a cultivar with vigorous growth and deep pink bracts, and 'Enduring Pink', a cultivar with pink bracts early colored. 'Red Stone' was finally selected in 2009 after the investigation of the growth and flowering characteristics from 2007 to 2009. 'Red Stone' has red elliptic bracts and strong rugosities between bract veins. Leaf blade is ovate and very dark green. Stem color is reddish and petiole length is medium but relatively longer than that of 'Pepride Red', control cultivar. 'Red Stone' develops as many as 3.8 branches and which is more than double of 'Pepride Red'. Its bracts and transitional leaves are fully colored at 7.5 weeks after short-day commencement. Plant variety protection right of 'Red Stone' was registered in April 2011, and its grant number is 3487.

• Journal of agriculture & life science
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• v.45 no.2
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• pp.29-34
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• 2011

This study was carried out to investigate the flower yield and quality of Lilium Oriental Hybrids as affected by planting date. In cut flower production experiments, effect of planting date and bulb source was studied in rain shelter houses with 30% shading. Four planting dates compared were May 15, June 5, June 25, and July 15. Bulbs used for cut flower production were either imported or produced domestically. The greatest cut flower yield and quality were obtained from bulbs planted either on May 15 or June 25. Bulbs planted on July 15 produced cut flowers of very poor quality and yield, due to high temperatures during the planting time. Therefore, for planting in July, means other than 30% shading have to be adapted to lower temperature during early growth stage. Although plants from imported bulbs had better growth and cut flower yield as compared to domestic bulbs, there was no significant difference.