• The Korean Journal of Ecology
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• 제23권6호
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• pp.431-434
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• 2000

To examine the allelopathic potentials of Chrysanthemum boreale, aqueous extracts and essential oil of the plant were used in these experiments. Seed germination of the receptor species was inhibited by the aqueous extracts and the inhibitory effect was increased in proportion to the concentration of extracts. In contrast, seedling elongation showed varied results. Achyranthes japonica, Bidens bipinnata, Raphanus sativus var. hortensis for. acanthiformis, Plantago asiatica, Pimpinella brachycarpa and Lactuca sativa were inhibited by increasing concentration of the aqueous extract, while Brassica campestris subsp. napus var. pekinensis and Echinochloa crus-galli were stimulated by the extract. Dry weight was also inhibited proportionally by increasing concentration of the aqueous extract, while some species were stimulated by a lower concentration of the extract. The volatile substances of C. boreale did not affect the seed germination of receptor plants, but seedling elongation and dry weight of some species were inhibited dose-dependently. Root hair development of selected plants was inhibited along with the concentration of essential oil. The above mentioned results, therefore, confirmed that the natural substances from C. boreale had allelopathic potentials to other plants.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권5호
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• pp.1-10
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• 2019

The effects of liquid phase ozonation on seed dormant alleviation and subsequent seedling growth were studied using two plant seeds of Indian jointvetch (Aeschynomene indica L.) and Indian mallow (Abutilon avicennae Gaertn.). At a constant ozone concentration ($80g/m^3$), contact time varied from 10 to 60 min with 10 min interval. Germination rate, root length, and specific root length were compared after 3-day incubation on gel-medium. The germination rate increased significantly (p<0.05) in the 50 min treatment of Indian mallow by 30% compared to the control. Enhanced root elongation was observed in the seeds of 30 min treatment of Indian jointvetch and 30~50 min treatment of Indian mallow. Specific root length, an indicator of environmental change, did not show significant changes, suggesting the level of ozone treatment has no adverse effect on seedling development. The results indicate that liquid phase seed ozonation can be an effective on-site germination alleviation method in the application of phytoremediation.

• 한국작물학회지
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• 제37권6호
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• pp.534-540
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• 1992

벼 건답직파재배에서 온도와 파종심도를 달리 하여 벼 품종의 출아와 중배축 신장을 조사한 결과를 요약하면 다음과 같다. 1. 온도가 높고 파종심도가 얕을수록 출아율이 높았으며 출아소요기간이 짧았다. 2. 각 처리온도 별로 파종심도 3cm이하에서는 출아율이 큰 차이가 없었으나 5cm이상이 되면 현저히 낮아졌다. 3. 파종 30일 후의 초장과 엽수는 온도가 낮을수록 감소하였고 파종심도가 5cm 이상이 되면 생육이 현저히 저하하였다. 4. 온도가 높고 파종심도가 5cm 이상일 때는 중배축과 하위절간의 신장이 컸다. 5. 파종심도 6cm에서 벼 품종들 중 출아율이 높았고 품종은 오수벼, 탐진벼이었고 중배축의 신장은 품종간 차이가 현저하여 5～16mm의 분포를 나타내었으며 제 1본엽의 출현이 지중 3～4cm에 이루어져서 파종심도는 지중 3～4cm가 적당한 것으로 판단되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1990년도 춘계 학술대회지
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• pp.30-31
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• 1990

• Molecules and Cells
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• 제45권4호
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• pp.243-256
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• 2022

Transcriptional regulation, a core component of gene regulatory networks, plays a key role in controlling individual organism's growth and development. To understand how plants modulate cellular processes for growth and development, the identification and characterization of gene regulatory networks are of importance. The SHORT-ROOT (SHR) transcription factor is known for its role in cell divisions in Arabidopsis (Arabidopsis thaliana). However, whether SHR is involved in hypocotyl cell elongation remains unknown. Here, we reveal that SHR controls hypocotyl cell elongation via the transcriptional regulation of XTH18, XTH22, and XTH24, which encode cell wall remodeling enzymes called xyloglucan endotransglucosylase/hydrolases (XTHs). Interestingly, SHR activates transcription of the XTH genes, independently of its partner SCARECROW (SCR), which is different from the known mode of action. In addition, overexpression of the XTH genes can promote cell elongation in the etiolated hypocotyl. Moreover, confinement of SHR protein in the stele still induces cell elongation, despite the aberrant organization in the hypocotyl ground tissue. Therefore, it is likely that SHR-mediated growth is uncoupled from SHR-mediated radial patterning in the etiolated hypocotyl. Our findings also suggest that intertissue communication between stele and endodermis plays a role in coordinating hypocotyl cell elongation of the Arabidopsis seedling. Taken together, our study identifies SHR as a new crucial regulator that is necessary for cell elongation in the etiolated hypocotyl.

• 한국토양비료학회지
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• 제10권1호
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• pp.7-12
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• 1977

작물생육(作物生育)과 토양물리성(土壤物理性)과의 관계(關係)를 구명(究明)코져 우리나라의 대표적(代表的) 밭토양(土壤)인 상주(尙州) 사양토(砂壤土), 연곡(延谷) 양토(壤土), 화동(華東) 미사질(微砂質) 식양토(埴壤土)를 갖이고 수분함량(水分含量)과 가비중(假比重)을 달리하여 Core를 만들어서 토양(土壤)의 경도(硬度)와 완두뿌리의 신장속도(伸長速度)를 측정(測定)하였던 바 그 결과(結果)는 다음과 같다. 1. 토양경도(土壤硬度)는 가비중(假比重)이 증가(增加)할수록 커지며, 수분함량(水分含量)이 많을수록 가비중(假比重) 증가(增加)에 따른 경도변화(硬度變化)는 적어진다. 2. 동일(同一)한 수분함량(水分含量)에서 뿌리의 신장(伸長)과 가비중(假比重)과는 고도(高度)의 상관(相關)을 보여 주었으며 그 기울기는 수분함량(水分含量)이 적을수록 컸다. 3. 완두뿌리의 신장(伸長)은 경도(硬度)(Yamanaka 경도계(硬度計) 및 침경도계(針硬度計))가 증가(增加)할수록 감소(減少)되었으며, 두 인자(因子)간에는 고도(高度)의 유의(有意)한 상관(相關)이 있었다. 4. 완두생육에 있어서 최저(最低) 뿌리 신장속도(伸長速度)를 0.3mm/hr(최대신장속도(最大伸長速度)의 약(約) ${\frac{1}{4}}$에 해당(該當))라고 보면 금속침(金屬針)에 의한 토양경도(土壤硬度) $21kg/cm^2$, Yamanaka경도(硬度) 24mm이 완두재배(栽培)에 있어 한계경도(限界硬度)라고 볼 수 있다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.151-151
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• 2017

In Asia, rice production has some difficulties with reduction of farm household population and increase of elderly population. As a result, it has resulted in inefficiency and we needs to reduce labor force and improve labor productivity. Direct-seeding in rice could reduce labor and production costs, the area of direct seeding is increasing in japonica rice production in Asia. In direct seedling cultivation competition against weeds is one of most important concern. So, low temperature germinability and mesocotyl elongation should be considered. In this study, we evaluated the mesocotyl length and low temperature germination conducted association analysis using 137 korea core collections. An average length of mesocotyl among 137 core collections was skewed range from 0mm to 43mm. we searched candidate gene around target SNP. Such related traits, genome-wide association study (GWAS) analysis was carried out using GAPIT. Also, average mesocotyl length of 394 korea landrace cultivars was measured ranging from minimum 0 mm to maximum 34mm. 30 out of 394 Korea landrace cultivar conducted re-sequencing, and haplotype analysis of candidate gene. we searched these related resources, which including germination of low temperature and mesocotyl elongation. This could be used for the development of direct-seeding cultivars. The valiated accession of core collection and landrace cultivars will be used development of direct-seedling cultivar in the future.

• 한국작물학회지
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• 제42권5호
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• pp.548-555
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• 1997

1. 낮은 농도의 지베렐린 처리에서는 돌연변이종의 절간장이 야생종보다 훨씬 많이 신장되어 지베렐린에 의한 절간 신장현상은 파이토크롬 B를 통하여 이루어짐을 보였다. 2. 고농도의 GA처리시 이들간의 초장 및 절간장의 차이는 나타나지 않아 고농도의 지베렐린에 의한 절간신장효과는 파이토크롬 B에 의존하지 않았다. 3. GA$_3$ 처리 후 내생 지베렐린의 함량을 조사한 결과 파이토크롬 B 변이종과 야생종간에는 큰 차이를 보이지 않음에도 불구하고 절간 신장률은 변이종이 야생종보다 현저하여 파이토크롬 B가 지베렐린의 반응 정도를 조절함을 입증하였다. 4. GA 생합성 억제제에 의한 내생 지베렐린의 합성이 억제된 경우 파이토크롬 B 변이종과 야생종간의 절간신장은 차이를 보이지 않아 파이토크롬의 절간신장효과는 지베렐린을 통해 일어남을 알 수 있었다.

• 한국작물학회지
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• 제45권1호
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• pp.50-54
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• 2000

The elongation of mesocotyl and coleoptile plays important roles in the seedling emergence and stand establishment of dry direct-seeded rice. Experiments were carried out to elucidate the effects of seed-presoaking treatments of GA$_3$ and some inorganic salts on the mesocotyl, and coleoptile elongation of rice. Seed-soaked GA$_3$ promoted the elongation of mesocotyl, but little effect on the coleoptile elongation. The stimulation effects of GA$_3$ were found to be enhanced by addition of CaCl$_2$ However, the sole treatment of CaCl$_2$ showed no stimulating effect on the mesocotyl and coleoptile elongation. Mesocotyl elongation was most prominent in the combined treatments of 50ppm GA$_3$ with 100 mM CaCl$_2$. The synergistic effects of GA$_3$ and CaCl$_2$ on mesocotyl elongation varied with varietal groups. The stimulating effects of GA$_3$ were enhanced significantly by the addition of CaCl$_2$ in japonica varieties, Dongjinbyeo, Ilpumbyeo and Milyang 95, and tall indica variety, Labelle, but not in semidwarf Tongil type varieties, Tongilbyeo, Milyang 23, and Nampungbyeo, and semi-dwarf indica, Short Labelle. The promoting effects of GA$_3$ on the mesocotyl elongation were decreased in proportion to the lowered osmotic potential by PEG 6000 on the contrary to CaCl$_2$ This implies that the synergistic effects of CaCl$_2$ with GA$_3$ on mesocotyl elongation was not caused by osmotic potential lowered by CaCl$_2$ addition but by the salt itself. Salts such as Ca(NO$_3$)$_2$, MgCl$_2$ BaCl$_2$, NaCl, KCl and KNO$_3$ showed the synergistic effects with GA$_3$ on mesocotyl elongation as well. The degree of synergistic effects showed no differences among salts tested, implying that there is no specificity of ions constituting the salts.

• 한국작물학회지
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• 제31권4호
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• pp.447-453
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• 1986

콩 품종(williams)의 발아와 묘신장을 두 온도, 세 종자, 수분함양 및 Polyethylene glycol-800(PEG) 처리와 무처리에서 측정하였다. 분할구배치법 사반복으로 실시하였으며 시료를 2시간부터 8일까지 각처리 조합에서 채취하였다. 콩 종자를 0.2% Thiram을 첨가한 30% PEG 여액에 놓아 15$^{\circ}C$에서 6 일간 침청후 증류수로 선정하여 25.5$^{\circ}C$에서 3 일간 건조하여 10개의 처리 또는 무처리 종자를 plastic petri-dish안의 9 cm 여과지에 놓아 수분함양에 정당한 증류수를 첨가하였다. Parafilm으로 밀봉하여 항온무광조건의 처리 온도에서 발아시켰다. 수분함양이 50% 또는 이하인 처리에서는 두 온도 모두 묘신장이 일어나지 않았다. PEG를 이용한 삼투처리는 15$^{\circ}C$에서는 묘수분 흡수와 체신장간에 정의 상관 효과를 보였으나 3$0^{\circ}C$에서는 거의 없었다. 종자 또는 묘수분함량은 발아기간동안 초기에 급속히 증가하여 15$^{\circ}C$에서는 56시간에, 그리고 3$0^{\circ}C$에서는 28시간에 60%에 도달하였다. 묘신장은 종자수분함양이 15$^{\circ}C$에서는 60%에서 시작되었지만 3$0^{\circ}C$에서는 20시간에 시작되었다. 콩묘는 15$^{\circ}C$에 비하여 3$0^{\circ}C$에서 사배 이상 신장되었다. 발아기간 동안의 수분흡수양상은 이 시험에서는 두 단계로 특정되었다.