• Journal of Ginseng Research
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• 제33권1호
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• pp.65-71
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• 2009

This experiment was done to determine the optimum conditions for the induction of tetraploidy in Panax ginseng C. A. Meyer using bud length, temperature and plant growth regulator pretreatments. Highest callus formation was obtained when the medium was inoculated with flower bud in the size of 2-3 mm in length. The optimum temperature for the callus formation was high when treated at $4^{\circ}C$ for 4-5 days. Among the treatments of growth regulators and different concentration, highest callus formation was observed in combination of 5 mg/L 2,4-D and 1 mg/L kinetin for P. ginseng. As a result of flow cytometer analysis, all 7 adventitious roots were confirmed as tetraploidys. Cytological analysis revealed that the chromosome number of tetraploid roots was 96, while that of diploid roots was 48. Tetraploid ginseng roots were inoculated to flower bud size of 2-3 mm in length. The callus formation was optimum when treated with 1 mg/L 2,4-D at $4^{\circ}C$ for 5 days. Compared with control roots, tetraploid roots were thicker and longer and had few lateral branches. Fresh weight of tetraploid roots was relatively higher than the control roots.

• The Plant Pathology Journal
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• 제23권3호
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• pp.223-225
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• 2007

Many plant growth-promoting rhizobacteria (PGPRs) have been known for beneficial effects on plants including biological control of soilborne pathogens, induced systemic resistance to plant pathogens, phytohormone production, and improvement of nutrient and water uptake of plants. We developed a simple and rapid method for screening potential PGPR, especially phytohormone producing rhizobacteria, or for analyzing their functions in plant growth using cucumber seedling cuttings. Surface-sterilized cucumber seeds were grown in a plastic pot containing steamed vermiculite. After 7 days of cultivation, the upper part 2 cm in length of cucumber seedling, was cut and used as cucumber cuttings. The base of cutting stem was then dipped in a microcentrifuge tube containing 1.5ml of a bacterial suspension and incubated at $25^{\circ}C$ with a fluorescent light for 10 days. Number and length of developed adventitious roots from cucumber cuttings were examined. The seedling cuttings showed various responses to the isolates tested. Some isolates resulted in withering at the day of examination or in reduced number of roots developed. Several isolates stimulated initial development of adventitious roots showing more adventitious root hair number than that of untreated cuttings, while some isolate had more adventitious root hair number and longer adventitious roots than that of untreated control. Similar results were obtained from the trial with rose cuttings. Our results suggest that this bioassay method may provide a useful way for differentiating PGPR's functions involved in the development of root system.

• 한국작물학회지
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• 제46권3호
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• pp.176-179
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• 2001

Source와 sink의 상대적 크기가 다른 고구마 품종간 이면접목을 통하여 생육에 미치는 고구마의 source와 sink의 상호관계를 분석함으로써, 고구마의 품종육성 및 재배법개선에 필요한 기초자료를 얻고자 수행한 결과를 요약하면 다음과 같다. 1 만장, 괴근수는 접목에 의하여 감소되었으며, 접목조합에 따라서 차이가 있었다. 2. 지상부의 생육은 접수, 지하부의 생육은 대목의 영향을 많이 받았다 3. 주만장과 괴근수에 대한 접목효과, 접수와 대목의 효과와 이들 간의 상호작용은 모두 유의성이 있었다. 4. 상저비율은 보통삽식＞자가접목＞이면접목 순으로 높았다.

• The Plant Pathology Journal
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• 제25권3호
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• pp.231-235
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• 2009

Viral infections and root growth were examined to elucidate the relationship between viral resistance and root growth in 26 Korean hulless barley cultivars. Viral resistance was estimated in experimental filed of Honam agricultural research institute for 3 years. Length and number of seminal and adventitious roots were examined for evaluation of root growth in both field and green-house conditions 30 days after seeding. Dominant viral infection occurred in Korean hulless barley by Barley yellow mosaic virus (BaYMV) in fields; however, susceptible cultivars were infected by either BaYMV, Barley mild mosaic virus (BaMMV) or both. Only four cultivars, including Donghanchalssalbori, Kwangwhalssalbori, Namhossalbori and Naehanssalbori, presented stable resistance to viral infections. Susceptible cultivars to viral infection in fields showed shorter seminal root length and fewer adventitious root number than resistant cultivars. Resistant cultivars showed better root growth and significant difference in adventitious root length in green house conditions. Increase in the number of seminal roots in resistant cultivars was derived from decreased damage of roots by the viral infection compared to the susceptible cultivars.

• 한국작물학회지
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• 제43권3호
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• pp.161-167
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• 1998

Root and shoot development of two rice (Oryza sativa L.) cultivars with different genetic backgrounds was studied with reference to their relative growth. Tongil type (indica-japonica hybrid) cultivar 'Kuemkangbyeo' and japonica cultivar 'Koshihikari' were grown in $5000^{-1}$ a Wagnar pots under flooded condition. Three plants with roots of both cultivars were taken in every phyllochron through the heading stage to record morphological characteristics of shoot and root system. Compared to Koshihikari, Kuemkangbyeo produced more tillers and had greater shoot weight and leaf area per hill. Length and weight of the root system in both cultivars increased exponentially with time. At the same time, root system development was significantly faster in Kuemkangbyeo than in Koshihikari after the panicle initiation stage. As a result, Kuemkangbyeo has a vigorous root system which consists of larger number of nodal roots compared to Koshihikari. Also, the root length and weight per unit leaf area of Kuemkangbyeo were larger than those of Koshihikari in the later half of growing period, which suggests possible higher physiological activity of the root system of Kuemkangbyeo which is known as a high-yielding cultivar. The relationship between root traits (crown root number, total root length, and root dry weight) and shoot traits (leaf area and leaf+culm dry weight) in both cultivars closely showed allometry until the flag leaf stage.

• 한국연초학회지
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• 제11권2호
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• pp.197-202
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• 1989

This experiment was conducted to investigate the effect of growth medium in pots composed of upland soil(S), rice straw manure(M), carbonated rice hull(CRH), and their mixture on growth of tobacco cv. NC 82. The growth of shoot and root was vigorous in order of medium S+M+CRH>M>CRH>S. In M+S medium, root growth in the part of manure was superior to upland soil. But root growth of upland soil part in M+S plot was more vigorous than that in upland soil only. It is possibly due to be influenced by manure in M+S plot. Total length and weight of root, number of roots, and especially for development of adventitious root were closely related to shoot growth. Roots grown in upland soil part was brownish gray in color, while the roots in manure part was milky white. The milky white colored roots had longer life than others. It was concluded that root zone environments derived from several media in pots closely related to shoot growth and disease tolerance of tobacco plant.

• 한국작물학회지
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• 제25권1호
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• pp.8-13
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• 1980

일본형품종과 원녹교잡수칭품종의 근부특성을 알기 위하여 진흥과 수원258호를 공논하여 발근이 거의 완료되는 출수기를 중심으로 근부특성을 조사한 결과 수원258호는 진흥에 비해 1차근수가 적고 1차근 평균근장도 짧으나 2, 3근의 분지세근 발달이 현저하며 근선단부위의 활력도 높아 양수분의 흡수기능상 유리한 근계를 가친 것으로 보였다.

• 한국환경과학회지
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• 제12권11호
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• pp.1189-1196
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• 2003

The effect of boron and aluminum on the development of adventitious roots was studied in sunflower cuttings. Three-day-old seedlings were de-rooted and grown in nutrient solutions with or without boron and supplemented with different concentrations (from 50 to 700 ${\mu}$M) of aluminum. The number and length of the adventitious roots and proline content in adventitious roots in response to insufficient boron and aluminum stress were determined periodically. The micronutrient boron caused the development of numerous roots in the lower parts of the hypocotyl. A dose-response of boron-induced rooting yielded an optimum concentration of 0.1 mM boron. In the absence of boron, in the majority of the adventitious roots, a significant inhibition was observed with or without aluminum, indicating that the most apparent symptom of boron deficiency is the cessation of root growth. Increasing concentrations of aluminum caused progressive inhibition of growth and rooting of the hypocotyls, and a parallel increase in proline levels of adventitious roots. Supplemental boron ameliorated the inhibitory effect of aluminum, suggesting that aluminum could inhibit root growth by inducing boron deficiency. Ascorbate added to medium in the absence of boron improved root growth and induced a significant decrease in proline levels. These findings suggest that adventitious root growth inhibition resulting from either boron deficiency or aluminum toxicity may be a result of impaired ascorbate metabolism.

• 생물환경조절학회지
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• 제17권1호
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• pp.14-19
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• 2008

저온기의 딸기 재배를 위한 기초자료를 얻기 위하여 '아키히메(章姬)'품종을 재료로 딸기의 뿌리 발달에 미치는 저온의 영향과 지하부의 온도와 관련된 지상부의 생육을 조사하였다. $18^{\circ}C$의 근온처리구에서 1차근의 생육이 가장 양호하였으며 $8^{\circ}C$의 저온에서 뿌리의 신장률이 가장 낮았으며, 특히 측근의 수와 길이가 가장 저조하였다. 근부의 온도는 지상부의 생육에도 직접적인 영향을 미쳐서, 낮은 근권 온도에서는 지상부의 생체중, 엽면적, 엽장, 엽폭 및 엽수의 저하를 초래하였다. 본 실험의 결과는 지하부 온도관리의 중요성을 확인할 수 있는 것으로 딸기 촉성재배농가에 유용한 정보로 활용될 수 있을 것이다.

• 한국자원식물학회지
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• 제34권4호
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• pp.270-277
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• 2021

산꼬리풀[Veronica rotunda var. subintegra (Nakai) T. Yamaz.]은 한반도의 전국 산지에 분포하는 다년생 초본식물이다. 초장은 40 ~ 80 cm로 전초는 기관지염을 치료하는 약용식물로 사용되며 7 ~ 8월에 피는 꽃은 정원용이나 절화 소재로도 이용할 수 있어 신 관상식물로서 가치가 있다. 본 연구는 산꼬리풀의 영양번식 체계를 확립하기 위하여 식물생장조절제, 삽목용토, 삽수부위, 잎 절단 처리에 따른 발근 효과를 구명하고자 실시하였다. 2017년 3월 국립수목원 식물자원연구과 부속온실에서 채취한 삽수는 생장조절제의 종류 및 농도, 삽목용토, 삽수부위, 잎 절단 처리를 한 후 6주간 삽목상에 두고 관찰하였다. 식물생장조절제 처리 실험에서는 100 mg/LIBA 처리구에서 근수, 신초 길이가 증가하였고, 고농도에서 신초의 발생이 감소하는 경향을 보였다. 삽목용토 실험에서는 원예상토 단용 처리구에서 녹소토 단용 처리구보다 근수는 19.4개, 신초 길이는 4.8 cm 더 증가하였다. 삽수 부위 실험에서 근수는 정단부에서 56.6개로 기부보다 17.8개 증가하였고 신초 길이도 1.8배 증가하였다. 잎 절단 실험에서는 none-cut 처리구에서 근수와 신초 길이가 cut 처리구보다 각각 17.3개, 1.9개 증가하였다. 본 연구의 모든 처리구에서 뿌리가 형성되었고, 고농도의 생장조절제 처리를 제외한 모든 처리구에서 신초가 형성되어 산꼬리풀은 삽목이 잘되는 종으로 판단되었다. 또한, 정단부의 삽수를 채취하여 삽수에 붙어있는 잎은 자르지 않고 원예상토에 삽목하는 것이 뿌리와 신초 발달을 증가시켰다.