• Journal of Forest and Environmental Science
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• v.37 no.4
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• pp.338-340
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• 2021

Morus alba, known as White Mulberry, is one of the most common species of mulberry found in South Korea, along with M. australis, known as Korean Mulberry. During a routine survey to investigate fungal diseases on deciduous broad-leaved trees in 2020, leaf spots were consistently observed on the White Mulberry in Sejong-si (36°30'12.8"N 127°17'34.5"E) and Wonju-si (37°15'29.6"N 128°11'37.9"E), South Korea, with a disease incidence of approximately 70 to 80%. Symptoms included circular, tan or necrotic lesions surrounded by a dark margin on leaves, which, in some cases, the lesions coalesced to form relatively large necrotic regions. The pathogen was successfully isolated from M. alba, and was identified as Cladosporium pseudocladosporioides based on the phylogenetic analysis and morphology. To the best of our knowledge, this is the first report of leaf spot disease on M. alba caused by C. pseudocladosporioides in South Korea.

• Journal of the Korean Professional Engineers Association
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• v.10 no.3
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• pp.8-16
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• 1977

The pbjective of this study to clarify the varietal resistance to green leaf-and planthopper and the evaluate the nature of the resistance to the insects in connection with the Antibiosis. this study was investigated the reaction of the varieties to insects with 46 rice varieties including recommended varieties of korea, At seedling stage they were in fested with second of third inster nymphs. the results were as follows. 1. Most of the rice vari eties tested showed highly susceptible reaction to Brown planthopper except Mudgo, KR 108-143- and HR529-41-3-2 as resistance, and Akamoch, Satominori, IR 24 and IR 8 asmoderately suscptible. 2. In the test of varietal resistance to white backed planthopper Mudgo, KR 108-243-1, KR 109-154-2 and HR 529-45-3-2 were resistance, and Suweon 82, Tongil, IR 8 palkeum, Iri 309, Hokwang and Chuhoku #31 were Moderatly susceptible. 3. Most of the varieties tested were observed highly resistance to green leafhopper, but Tongil, Suweon 82, IR 24, Milsung and Chuhoku #31 were Moderatly susceptible. 4. the new bred lines HR 108-243-1 are multiple resistance of Brown planthopper, green leafhopper and white babked planthopper, and some others showed moderatly susceptible as. IR 8: Brown planthopper, white backed planthopper. IR 24: Brown poanthopper, green leafhopper. Tongil: suweon #82, Chukoku #31, whist backed planthopper, Green leafhopper.

• Journal of Plant Biotechnology
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• v.34 no.3
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• pp.223-227
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• 2007

Plant regeneration system from leaf and root segments of Lycoris chejuensis via bulblet formation was established. Surface-sterilized leaf and root segments were cultured on the B5 medium containing 2,4-D. After 12 weeks of culture onto B5 medium containing 2,4-D, white globular structures and white calluses were formed on the cut surface of the explants. The highest frequency of globular structures and calluses formation from leaf explants was 32.1% when leaf explants were cultured onto B5 medium supplemented with 1 mg/L of 2,4-D. However, the higher concentration of 2,4-D (over than 3 mg/L) resulted in decrease of the frequency. In comparison to leaf explants, root segments showed the highest frequency at a rate of 36.1% when root explants were cultured onto B5 medium supplemented with 3 mg/L of 2,4-D. These structures and calluses were sub-cultured and proliferated onto the same culture medium. Upon transfer to B5 basal medium, white globular structures were developed into bulblets and normal plantlets. After 4 weeks of incubation in the light, plantlets were successfully rooted over the frequency of approximately 90%. Rooted plantlets were successfully transferred to potting soil and acclimatized in the growth chamber. The plant regeneration system of Lycoris chejuensis established in this study, might be applied to mass proliferation, conservation of genetic resources and genetic transformation for molecular breeding.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.27-32
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• 1995

A new flue-cured tobacco mutant line BU 8832-85 was developed at Taegu Experiment Station, Korea Ginseng and Tobacco Research Institute in 1994. KF 8832-85 was resulted from a cross of flue-cured cultivars NC 95$\times$NC 2326, and developed by a pedigree system of breeding ; initial selection was made by plant type and resistance to bacterial wilt(BW) disease(heudomonas solanaceamm) in the F2 generation under the natural field conditions infested with the pathogen. One white flowered plant was occurred by spontaneous mutation in a certain line among the F3 generatioin while the others were pink. Six plants from the seeds by selfing were selected at the field infested with the pathogen among 240 populations with white flowering in the F4, KF 8832-85 was selected based on yield and leaf quality trials among 6 lines in Fs generation. BCF 8832-85 was compared with its Parent for certain agronomic and chemical characteristics at Taegu Experiment Station in 1993 and 1994. The results showed that KF 8832-85 have white flower, the stalk height was approximately that of NC 2326 but averaged about loom taller than NC 95. It produced ground suckers as much as NC 95, and did not breakdown leaf at the same as WC 2326. KF 8832-85 have high resistance to bacterial wilt disease. Yield of KF 8832-85 was 10 and 18% higher then that of NC 2326 and WC 95, respectively. Price per Kg was equal to that of NC 2326. The contents of nicotine and reducing sugar did not differ significantly from NC 95, while total nitrogen was significantly lower than NC 95. Therefore, the new mutant line is genetically stable for agronomic and chemical characteristics and provides a source of bacterial wilt disease resistance for use in breeding resistant flue-cured cultivars. Key words : Mutant line, White flower, Spontaneous mutation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.2
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• pp.15-22
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• 2022

This study has been conducted to investigate the appropriate mixed sowing rates with white clover (Trifolium repens) and Kentucky bluegrass (Poa pratensis) by evaluating initial growth. Six different mixed sowing rates (CT, Control Trifolium repens; CP, Control Poa pratensis; T1P3, Trifolium repens 1 : Poa pratensis 3; T1P2, Trifolium repens 1 : Poa pratensis 2; T1P1, Trifolium repens 1 : Poa pratensis 1; T2P1, Trifolium repens 2 : Poa pratensis 1; T3P1, Trifolium repens 3 : Poa pratensis 1) with three repetitions were implemented in greenhouse experiment plastic pots (50.5 length × 35.0 width × 8.5 cm height). Plant height, leaf length, leaf width, number of leaves, root length, fresh weight, and dry weight were measured after a week from the germination for three months. Initial growth of Kentucky bluegrass significantly increased as mixed sowing rates with increasing, while that of white clover kept relatively decreasing than that in Control. Initial growth strongly affected sowing mixed rates by Kentucky bluegrass and not by white clover in this experiment, indicating that grasses played a dominant role during initial growth period. However, seeding rates with white clover will be dependent on the use of a turf and the desired green cover. There remains a need to further study of the mechanisms and dynamics of legume and grass competition to underpin sustainable management practices.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.2
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• pp.81-90
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• 2003

This pot experiment was conducted to find out the effects of boron application(B$_{0}$; 0.0, B$_1$; 0.2, $B_2$;2.0, $B_3$;6.0, $B_3$;6.0, $B_4$;15.0me B/pot) on the forage performance in the pure and mixed swards of orchardgrass and white clover. This 1st part was concerned with the changes in the growth, flowers and flower buds, and roots/nodules of forages. The results obtained are summarized as follows: 1. At the $B_3$ and $B_4$ treatments, the B toxicity was more seriously in white clover than in orchardgrass in the first half of cutting orders, and reduced in the latter half. In white clover, it was more worsened in a mixture than in a pure culture. It was somewhat reduced at the best growth stage of each forage. 2. In orchardgrass, the B toxicity($B_3$,$ B_4$) showed the chlorosis on leaf tips, shallow leaf, little tillers, and weak stems. Whereas it showed the chlorosis/necrosis on old leaf edge, little and weak stolons in white clover. 3. Comparing with the B deficiency($B_{0}$ , $B_1$) and toxicity($B_3$, $B_4$), the optimum B application($B_2$) influenced markedly good growth of shoot, root, nodule, and flower (flower number, blooming period, early full flower) in white clover. 4. Comparing with orchardgrass, white clover was greatly influenced by the boron application. However, this responses of white clover to boron were reduced in a grass-clover mixture with additional fertilization. It was recognized that the good forage performance in a grass-clover mixture could be regulated by the adequate applications of boron and additional fertilizers.s.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.222-230
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• 2018

This study aimed to determine effects of light-emitting diodes on plant growth, leaf morphology and cell elongation of two cultivars ('World-star' and 'Sushiro') of Spinacia oleracea. Plants were grown in a NFT system for 25 days after transplanting (DAT) under the LEDs [White (W), Red and Blue (RB, ratio 2:1), Blue (B), Red (R) LED] under the same light intensity and photoperiod ($130{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 12 hours). The 'World-star' variety was significantly higher in shoot fresh and dry weights, leaf number, and leaf area than the 'Sushiro' variety. For the 'World-star' variety, the two treatments of mixed light (RB) and red light (R) showed a 35% higher shoot dry weight than that of blue light (B) and white light (W) at 25 DAT. In the 'Sushiro' variety, mixed light (RB) treatment, which had the highest shoot fresh and dry weights, showed 40% higher than the white light (W) treatment, which had the lowest shoot fresh and dry weights. Both varieties showed leaf epinasty symptom at 21 DAT only in both mixed light (RB) and red light (R), and red light (R) treatment showed significantly higher symptom than mixed light (RB), indicating the leaf epinasty is associated with red light. Microscopic observations of the cell size in the leaf center and edge parts showed that the cell density of leaf edge under the red light (R) was lower than that in leaf center, supporting previous reports that suggest an association of the cell size difference between the leaf center and edge with the leaf epinasty occurrence. Since the blue light (B) plays a role in alleviating the epinasty symptom caused by the red light (R), it seems necessary to identify the appropriate mixing ratio of the two light sources. In addition, the World-star variety seems to be more suitable for the cultivation of plant factory using LED light sources.

• Korean Journal of Medicinal Crop Science
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• v.15 no.1
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• pp.6-11
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• 2007

This study was conducted to identify physiologically active substances from leaves and stems of peony plant. MeOH extracts and column chromatography were employed to isolate active compounds and chemical structure were identified by IR, UV, Mass and NMR. The results obtained can be summerized as followings : Chemical structure of compound 1 was identified as oleanolic acid (white color form) of triterpenoid group, which is firstly identified from the above part of peony. Compound 2 was identified as kaempferol (yellow needle form) of flavonoid group, which was firstly identified from the root, leaf and stem of peony. Compound 3 was identified as methyl gallate (white power form) of phenol group, which was firstly identified from the above part of peony. Compound 4 was identified as astragalin (bright yellow needle form) of flavonoid group, that was firstly identified from the leaf and stem of peony. Compound 5 was identified as paeoniflorin (white color form) of monoterpene group, that was firstly identified from the above part of peony.

• Journal of Ginseng Research
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• v.17 no.2
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• pp.145-147
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• 1993

The amounts of ginseng acidic polysaccharide (GAP) in red ginseng (Panax ginseng) were higher than those of wild and cultured Panax quinquefolius, Panax notoginseng as well as white ginseng (Panax ginseng). In white ginseng, there is no difference in the GAP amount among root ages or sizes. Also, the GAP amount of red ginseng body was similar to that of ginseng rhizome, but was higher than that of leaf and epidermis.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.1
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• pp.103-106
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• 2003

Among silkworm diseases, white muscardine is the most virulent and contagious disease caused by Beauveria bassiana and common during winter and rainy seasons. The disease is managed at present by practicing the silkworm body and rearing seat disinfection to prevent the spread of white muscardine during silkworm rearing as the available methods do not cure the silkworms against white muscardine. The use of systemic fungicide was suggested recently to control white muscardine. The present study investigated the practicability of application aspect of systemic fungicide as spray, It is observed that 3 times feeding of systemic fungicide through mulberry leaf, fed immediately after third, fourth moult and on $4^{th}$ day of final instar as most effective in suppressing the multiplication of the fungus in silkworm. Spraying of the systemic fungicide on mulberry in the rearing house, air-dried and feeding was suggested as suitable application method. Alternately the spraying of the systemic fungicide on mulberry in mulberry garden 6 hrs prior to feeding was also suggested as a method for the control of white muscardine in silkworm rearing.