• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.143-147
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• 2013

'Sangdojosaeng' is a new cultivar from bud spot of Citrus unshiu 'Sasaki unshiu' which has late maturity habit. It was found in 1996, and primary selected and named as 'JARES108' in 1998. 'JARES108' was grafted on to adult satsuma mandarin trees in Seogwipo-si and Jeju-si in 2000. Four years survey on the characteristics of trees and fruits from 2003 to 2006 was carried and confirmed the superiority. Thus it was finally selected as 'Sangdojosaeng'. 'Sangdojosaeng' is a very early wase type satsuma mandarin. It shows relatively strong tree vigor among the very early wase type varieties and its branches are spreading. Its ripening time is late October, 25 days earlier than 'Sasaki unshiu'. Compared to 'Ueno wase' which has similar characteristics with 'Sangdojosaeng' such as ripening time, tree vigor, fruit type and peel color, its soluble solid content of fruit is $0.6^{\circ}Bx$ higher and acidity was a little lower than 'Ueno wase'. Because this cultivar has good quality and its tree makes vigorous growth among very early wase type varieties in Jeju, we expect to substitute it for some very early wase type varieties such as 'Miyamoto wase', 'Ichifumi wase', 'Yamakawa wase', etc.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.8 no.1
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• pp.91-97
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• 1970

It is one of the important subjects in fall crop production of potatoes in korea to find the proper direct planting method as a substitute for transplanting method by sprouting inducement at seed-bed. From this point the author has undertaken this experiments to examine the effects of several handling methods of seed tuber pieces at planting on sprouting of fall grown potatoes at Ansung Agricultural College from August to september in 1969. The results of experiments induced sprouting with Gibberellin treatment using the variety Irish Cobbler were as follows; 1. Sun light exposure treatment to cut surface of potato seed pieces resulted in rotting of seed pieces and delay of sprouting and bud growth. Exposure more than three hours induced severe rotting(more than fifty percent) of seed pieces (Table I). 2. When soil moisture are abundant and the duration of sun light. exposure is short, even direct planting method of treated seed pieces with Gibberellin resulted in good potato stands (Table 2). 3. The direct planting method, as the rotting of seed pieces are avoidable are applicable in fall crop production of potatoes us a substitute for transplanting method because the sprouting and bud growth are promoted more in case of direct planting than transplanting (Table 3). 4. When the humidity in the bottle was low no healing effects was found by holding the seed pieces in large closed bottle under the trees for three days before planting (Table 2). 5. If duration of sunlight exposure is short, no difference of potato stands between clear day planting and cloudy day plant ing (Table 3). 6. As long as soil moisture deficiency. was not induced the irrigation at planting shows no effects to protect the seed piece rotting after planting (Table 3).

• Horticultural Science & Technology
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• v.32 no.3
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• pp.296-302
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• 2014

The foliage of variegated Solomon's seal is excellent in cut flower arrangements. However, it has a restricted marketing period because the harvesting is limited in spring and summer. The increased interest requires the year-round production, thus techniques for dormancy breaking and forcing without low temperature treatment is needed. Therefore, experiments were conducted to d etermine whether gibberellic acid (GA) could break dormancy in variegated Solomon's seal. Thes prouting of dormant bud did not occur throughout the experiment when $GA_3$ $400mg{\cdot}L^{-1}$ was applied to dormant rhizomes as a soil drench. However, when plants were treated with a GA drench after scratch with razor blade or were given direct injection of GA, percent sprouting was increased up to 100 or 83.3%, respectively. However, because treatments with razor or syringe may damage internal organs, we tested another method, scarifying the rhizomes with sodium hypochlorite (NaOCl). Rhizome scarification with 4% NaOCl for 6 or 24 hours followed by drench of $GA_3$ $400mg{\cdot}L^{-1}$ increased the dormancy breaking percentage to 70 or 86.7%, respectively. Moreover, scarified and GA-treated rhizomes produced more leaves than untreated or GA-soil drenched plants in the glasshouse. These results showed the possibility of year-round production of variegated Solomon's seal foliage with rhizome scarification and GA treatments.

• The Korean Journal of Pesticide Science
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• v.19 no.1
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• pp.22-31
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• 2015

This study was carried out to monitor the current status of pesticide residues in selling agricultural products via online and assessed their safety in 2014. A total of 124 samples were purchased six times from March to August 2014 twenty online shopping malls randomly. These samples were analysed 208 pesticides by multiresidue method using a GC-ECD/NPD and a LC-MS/MS and confirmed by a GC-MSD. As a result of analysis, residual pesticides samples were 11 (8.9%) such as leek, young radish, welsh onion etc, of which 2 samples (1.6%) such as sesame bud (Chlorothalonil), artemisia (Chlorpyrifos) were violated Korea Maximum Residue limits (MRLs). 11 kinds of pesticides (19 times) were detected in 11 samples. Risk assessment evaluated human health exposure with the ratio of EDI (Estimated daily intake) to ADI (Acceptable daily intake) of pesticides detected. %ADI (the ratios of EDI to ADI) were 0.04~95.70% and some samples represented a fairly dangerous levels. In particular, Chlorothalonil in the sesame bud was shown as a significant risk close to 100% of %ADI. Accordingly, it is recommended to strengthen a safety check on agricultural products in online sales.

• Journal of Korean Society of Forest Science
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• v.25 no.1
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• pp.73-79
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• 1975

The Koran native economic and ornamental trees consisting 12 species of 4 gymnosperm families and 3 strains, 6 varieties and 18 species of 12 angiosperm families were irradiated by X-and ${\gamma}$-ray at three different dose rates; 1) acute, 2) semi-acute, and 3) chronic irradiation in order to know their radiosensitivities and the radition effects on mutation induction. Different materials such as seeds, cuttings, scions and plants of the above trees were used in this study, depended upon tree. Most of the materials irradiated showed a high radiosensitivity. The LD-50 of conifer trees ranged from 1.2kR to 13.2kR, averaging 5.4kR which was remarkably higher than field crops. On the other hand the LD-50 dose of hard wood trees ranged from 7.0kR to 18.5kR, averaging 12.7kR. All the tested trees were classified into several categories based upon the relative radiosensitivity of each species which was measured at the dose of LD-50. Variegation was most common among the induced mutants. The other mutations were albino, chlorophyll deficiency, deformed leaf and fruits. It was noticeable that giant-leaf bud-sport mutants were induced in Chinese chestnut (Castanea bungeana) and yellow leaf bud-sport ones appeared in oriental arborvitae (Thuja orientalis).

• FLOWER RESEARCH JOURNAL
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• v.16 no.1
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• pp.12-16
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• 2008

This study was carried out to produce haploid plants to verify a systematic breeding program and genetic analysis. Effect of developmental stage of pollen grains and pre-treatment temperature on production of haploid plants was investigated. Microscopic investigation of the explants (Lilium Asiatic hybrid 'reamland' revealed that the length of flower bud at 23.0-24.9, 25.0-26.9, and 27.0-28.9 mm long coincided with tetrad, uninucleate, and binucleate, respectively. When the efficiency of the anther culture from microgametogenetic stages was tested, late uninucleate to early binucleate stage, having the length of 23.0 to 28.0 mm long flower bud, was the best. The frequencies of the callus induction and plant regeneration from the stage mentioned above were 17.8 and 6.7%, respectively. When calli were cultured on the MS medium containing picloram and zeatin at $25^{\circ}C$, shoots were obtained. Roots of regenerated plantlets were confirmed as haploid through an microscopic observation.

• Journal of Sericultural and Entomological Science
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• v.3
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• pp.13-21
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• 1963

1. In the mulberry groves for both rearing of spring and fall, the rate of germination was 74.3 percent and the rate of the unfinished bud was 25.7 percent. 2. When the summer pruning after spring rearing was not worked, new sprouted leaves from the axillary buds of an age old branches was 74.88 percent of germination and the rest from unfinished bud during the spring showed 28.12 percent. 3. In the furrows running from north to south, new buds facing the due north were the worst but towards south-east and north-east were the best in their sprouts. 4. One year-old branches which had been raised without the summer pruning in the bush types of Morus Lhou (ser) Koidz offered a habitat where Apriona Rugico1lis Cherr could live. 5. On the grove of Morus Lhou Koidz cultivated at lower zone under a higher humidity and the shortage of sun light the appearance of Anomoneura Mori Schw was likely to happen very much. 6. One year old branches without the summer pruning produced more leaves owing to a long period of growth than branches with the summer pruning in the fall crops. 7. It is necessary to reconsider a certain distance of planting because of causing, when the summer pruning was not made in the bush plantation, a obstacle of fertilizer operation or the forth coming year's management. 8. It can not be thought the ideal method for us to raise mulberry tree such as Morus Lhou Koidz under natural form and at a short distance of planting (one another). 9. Among the species, Morus alba L. had a great deal of leaves and of the rate of germination per unit length of branch.

• Plant Biotechnology Reports
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• v.4 no.2
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• pp.173-178
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• 2010

An efficient protocol for shoot regeneration was developed for sesame (Sesamum indicum L.) internodes using the transverse thin cell layer (tTCL) culture method. The frequency of shoot regeneration and the number of adventitious buds produced from regenerated shoots depend significantly on explant age, thickness of the tTCL sections, and the phytohormones supplemented to the culture medium. A combination of 6-benzyladenine (2.0 $mg\;l^{-1}$) and a-naphthaleneacetic acid (0.5 $mg\;l^{-1}$) was found to be the best phytohormone combination for shoot bud induction, with the maximum number of shoots obtained when the tTCL sections were 0.5-1.0 mm thick and derived from 4- to 6-week-old seedlings of sesame. Well-developed shoots were rooted on MS medium without phytohormones, and 80% of the regenerated plantlets were successfully established in soil.

• Plant Disease and Agriculture
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• v.5 no.1
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• pp.34-40
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• 1999

The virus infection rates and disease symptoms of three major citrus viruses, citrus tristeza virus (CTV), satsuma dwarf virus (SDV), and citrus tatter leaf virus (CTLV), were investigated at 35 citrus orchards in Cheju Island from 1995. The infection rates of CTV, SDV, and CTLV were 69.8%, 8.6%, and 9.3%, respectively. However, depending on cultivars there were significant differences in the infection rates. The infection rates of CTV were highest in early satsuma mandarin (Citrusunshiu) with 80.9% and lowest in very early satsuma mandarin with 51.9%. In SDV, the highest was in very early stasuma mandarin with 23.1% and the lowest was in early satsuma mandarin with 6.3%. And the highest infection rate in very early satsuma mandarin with 17.9% and the lowest in tangors with 7.3% in CTLV. The symptoms of virus-infected citrus were very diverse; small and abnormal shape of fruits, abnormal leaves such as narrow boat and small spoon shapes of leaves, stem-pitting on the twig, bud-union crease and swelling of the graft part, reduction of the plant vigor and poor yields.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.694-701
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• 2014

Allium hookeri L. (Alliaceae family) is an important ethnomedicinal plant native to the Himalayan region of Asia. The aim of this research was to establish a high-frequency plant regeneration system for in vitro propagation of A. hookeri. Among the tissue types examined, receptacle explants derived from immature flower buds showed the highest regeneration rate of shoots ($93.33{\pm}4.63%$), roots ($76.67{\pm}7.85%$), and calli ($80.00{\pm}7.43%$) when cultured on Gamborg B5 (B5) medium containing $10{\mu}M$ 6-benzylaminopurine (BA) + $1{\mu}M$ naphthalene acetic acid (NAA), $0.5{\mu}M$ BA + $5{\mu}M$ NAA, and $1{\mu}M$ BA + $10{\mu}M$ NAA, respectively. Shoot multiplication was superior when cultured in liquid rather than on solid medium and relatively high concentrations of BA, ranging from 5 to $10{\mu}M$. Efficient bulblet formation following root induction from shoot clumps was achieved with culture in liquid B5 medium containing 7% (w/v) sucrose. Regenerated bulblets were successfully acclimatized to ex vitro conditions with a greater than 95% survival rate. By this method, a maximum of 62 plantlets per receptacle could be propagated within 9 weeks of initial culture. The in vitro propagation system established in this study will promote A. hookeri biotechnology, including large-scale production of healthy and aseptic clones, preserving parental genotypes with desirable traits, and genetic manipulation to enhance medicinal value.