• The Plant Pathology Journal
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• 제20권2호
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• pp.97-102
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• 2004

Paenibacillus polymyxa E681, with its plant growth promotion and root colonization ability, has been proven to be a promising biocontrol agent of cucumber and barley. This study investigated the attributes related to the movement of bacteria from the seed to the radicle and to the whole root system. It also illustrated the existing form and population changes of the bacteria on seed and root using the scanning electron microscope and confocal laser scanning microscopy. The bacteria invaded and colonized the inside of the seed coat while the seeds were soaked in bacterial suspension. Almost the same number of bacteria on seed surface invaded the inside of the seed coat right after seed soaking. The population densities of E681 increased greatly inside as well as on the surface of the seed before the radicle emerged. The bacteria attached on the emerging radicle directly affected the initial population of newly emerg-ing root. The colonized cells on the root were arranged linearly toward the elongation of the root axis. In addition to colonizing the root surface, strain E681 was found inside the roots, where cells colonized the inter-cellular space between certain epidermal and cortical cells. When the cucumber seeds were soaked in bacterial suspension and sown in pot, the bacterial populations attached on both the surface and inside of the root were sustained up to harvesting time. This means that E681 successfully colonized the root of cucumber and sustained its population density up to harvesting time through seed treatment.

• Environmental Analysis Health and Toxicology
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• 제14권4호
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• pp.135-144
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• 1999

Environmental toxicities of priority water pollutants were evaluated by two selected bioassays, Lettuce seed germination/elongation test and Microtox acute toxicity test. Toxic chemicals (heavy metals, polycyclic aromatic hydrocarbons, and phenolic compounds) inhibited the germination rate and root elongation of Lettuce seed, as well as the bioluminescence of Microtox bacteria. When test biota were exposed to target chemicals, the sensitivity of Lettuce bioassay was relatively lower than that of Microtox bioassay. However, Lettuce bioassay may be a good candidate for prescreening the environmental toxicities of priority water pollutants, since the testing method with Lettuce seed was relatively easier and more economic than with Microtox bacteria. Toxicity tests were conducted to compare the validity and sensitivity of both bioassays for sediment from a small stream passed through urban area as well as leachate from a municipal solid waste landfill. From experimental results, we found that Lettuce test and Microtox test are compensated each other as a battery of bioassay for evaluating the environmental toxicities of field samples obtained from a small stream contaminated by pollutants.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.358-358
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• 2017

The plant type is generally one of the most important factor for crop production and be influenced by nitrogen absorption. Soybean plants have nodules in their roots, supplying nitrogen at the vegetative and reproductive stages. Root nodules seem to effect plant type of soybean plants, but there are few reports on the relation nodules and plant type. We tried to clarify the effects of root nodules on the plant type, especially internode length and petiole length, comparing non-nodule soybean with normal soybean. The pot experiment and field experiment were carried out at Mie University and Utsunomiya University in 2015 and 2016. Enrei, a popular cultivar in central Japan, and En1282, non-nodulating isogenic line of Enrei, were used. The petiole length on main stem was measured after defoliation and internode length and yield components were measured after harvest. In the field experiment, the patterns of the final length in internode and petiole on main stem were consistent in both cultivars, and a positive correlation was found between the Nth petiole length and the N-1th internode length, belong to the same phytomere. Therefore, the petiole and internode on the main stem make similar response for environmental factors. In pot experiment, Enrei grew with the same pattern as field experiments, but in En1282, the elongation of petiole and internode in the upper part was suppressed, especially the petiole was suppressed greatly. The main stem becomes the basis of the plant type. These results were considered that the nitrogen is distributed preferentially to the internode than the petiole. It seems that the pot cultivation restricted the rhizosphere and caused nitrogen deficiency in En1282. These results suggested that the slight nitrogen deficiency provided from the root nodules was compensated by the increase of the amount of inorganic nitrogen absorption due to the expansion of the rhizosphere, and the severe nitrogen deficiency suppressed elongation of petiole and internode. It is clear that root nodules effect the plant type by supplying nitrogen to internodes and petioles.

• 한국균학회지
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• 제45권1호
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• pp.74-82
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• 2017

꽃도라지(Eustoma grandiflorum)는 국내에서 장식용 화훼류로 널리 이용되는 절화류이다. 2015년 경기도 여주와 경남 김해 지역에서 꽃도라지가 시들고, 지제부가 잘록해지면서 위축되고, 뿌리가 썩는 증상이 나타났다. 병든 식물체는 포장이나 육묘상자에서 황화되고, 뿌리 발육이 저해되었고, 진전되면 전체적으로 황화되면서 시들고, 위축되며, 결국 2~3개월 안에 완전히 말라 죽는다. 병든 식물체 지제부에서 Fusarium균이 분리되었고, 9개 균주를 단포자 분리하여 형태적 특성을 조사한 결과, Fusarium solani로 동정되었다. 대형포자는 통통하고, 직선형이거나 약간 굽은 초승달 모양이고, 소형분생포자는 긴mono형태의 분생포자원세포에서 false head상으로 형성되었다. 후벽포자는 균사 중간 혹은 끝부분에 풍부하게 형성되었다. 이와 같은 동정 결과는 translation elongation factor 1 alpha (TEF)와 RNA polymerase II subunit (RPB2) 유전자의 염기서열 분석으로 재확인되었다. 그 결과, 분리 균주는 NCBI GenBank에 등록된 F. solani와 TEF 유전자는 99.2~99.9%, RPB2 유전자는 98.0~98.1%의 상동성을 나타내었다. 건전한 꽃도라지 유묘의 뿌리를 포자현탁액에 침지 접종하여 병원성 검정을 수행한 결과, 접종 7일 이내에 접종한 식물체에서만 병징이 관찰되었다. 따라서 이 병을 F. solani에 의한 꽃도라지 뿌리썩음병으로 명명하며, 병의 발생을 국내에서 처음으로 보고한다.

• Plant Biotechnology Reports
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• 제4권4호
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• pp.243-251
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• 2010

Nitric oxide (NO) has been shown to be involved in diverse physiological processes in microbes, animals and plants. In this study, the involvement of NO in the development and possible roles in oxidative stress protection of Chinese cabbage (Brassica rapa subsp. pekinensis cv. Samrack-ulgari) seedlings were investigated. Exogenous application of sodium nitroprusside (SNP) retarded root elongation, while increasing lateral root formation of Chinese cabbage. Plants showed no signs of external stress due to SNP application in true leaves. Cotyledons of 3-week-old Chinese cabbage plants were found to be highly sensitive to SNP application. Treated cotyledons displayed rapid tissue collapse and associated cell death. Although SNP application reduced root growth under normal growth conditions, it also enhanced methyl viologen (MV)-mediated oxidative stress tolerance. Analysis of SNP application to Chinese cabbage leaf disks, revealed SNP-induced tolerance against oxidative stresses by MV and $H_2O_2$, and evidence includes prevention of chlorophyll loss, superoxide anion (${O_2}^-$) accumulation and lipid peroxidation. This report supports a role for nitric oxide in modulating early seedling development, programmed cell death and stress tolerance in Chinese cabbage.

• 한국균학회지
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• 제50권4호
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• pp.319-329
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• 2022

In July 2020, wilting symptoms were observed among adzuki bean plants (Vigna angularis var. angularis L.) in the fields in Yeosu, Korea. Infected plants showed yellowing of leaves, browning inside the stems, splitting of stem bark, and wilting. When these plants were uprooted, their roots were found to be brown. The fungal pathogens NC20-737, NC20-738, and NC20-739 were isolated from symptomatic stem and root tissues. These pathogens were identified as a Fusarium fujikuroi species complex based on their morphological characteristics. Molecular identification was performed using the DNA sequence of translation elongation factor 1 alpha and the RNA polymerase II second largest subunit regions. The nucleotide sequences of all three isolates were similar to the F. fujikuroi reference isolates NRRL 13566 and NRRL 5538 of the National Centre for Biotechnology Information GenBank. A pathogenicity test was conducted by the soil inoculation method with cornmeal sand inoculum. Approximately 3 weeks after inoculation, symptoms were observed only in the inoculated adzuki bean seedlings. To the best of our knowledge, this is the first report of Fusarium root rot caused by F. fujikuroi in adzuki beans, both in Korea and worldwide.

• 한국산림과학회지
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• 제77권4호
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• pp.445-452
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• 1988

조직배양(組織培養)에 의(依)한 대추나무 신품종(新品種) 실용적(實用的)인 대량증식방법(大量增殖方法)을 구명(究明)하기 위(爲)하여 액아(腋芽)를 이용(利用), 기내생장(器內生長) 및 야외순화(野外馴化) 시험(試驗)을 실시(實施)한 결과(結果)는 다음과 같다. 1. BAP 0.5mg/l가 들어있는 1/2MS배지(培地)에 charcoal을 첨가(添加)하여 기내생장(器內生長)을 조사(調査)한 결과(結果), '금성(錦城)'의 경우(境遇) charcoal 500mg/l 처리(處理)하였을 때 줄기의 신장(伸張) 및 발생(發生)된 줄기의 수(數)가 각각(各各) 6.4cm, 10개(個)로 가장 높았고 '복조(福棗)'에서는 1,000mg/l 처리시(處理時) 7.5cm, 12.4개(個)로 가장 좋았다. 2. 조사(調査)한 IBA 농도중(濃度中), 그 농도(濃度)가 증가(增加)할수록 발근율(發根率) 및 callus 생장(生長)이 양호(良好)하였으며, IBA 1.0mg/l 처리구(處理區)에서 줄기의 생장(生長)이 가장 좋았다. 3. 조직배양(組織培養)에 따른 생장반응(生長反應)의 차(差)를 조사(調査)한 바, '금성(錦城)'의 경우(境遇) 발생(發生)되는 줄기수에 있어 액아(腋芽)가 정경(頂莖)보다 2배(倍)정도 많았으나 '복조(福棗)'에서는 정경(頂莖)이 줄기신장(伸張) 및 발생(發生)되는 줄기수(數)에 있어 액아(腋芽)보다 좋은 결과를 보였다. 4. 기내(器內) 배양묘(培養苗) 순화시험(馴化試驗)에서는 근원기(根原基)만 형성(形成)된 묘(苗)가 활차율(活差率)이 97.8%로 발근묘(發根苗)보다 월등(越等)히 높았다. 5. 온실내(溫室內) 삽목시험(揷木試驗)에서는 paclobutrazol 처리(處理)가 발근율(發根率) 및 뿌리생장(生長)에 있어 IBA, NAA, $Rooton^{(R)}$ 처리구(處理區)보다 효과적(效果的)이었다.

• 한국토양비료학회지
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• 제22권3호
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• pp.221-227
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• 1989

토성(土性)이 다른 두 토양(土壤)의 압밀상태(壓密狀態)가 대두(大豆)의 근생장특성(根生長特性)과 양분(養分)의 흡수기능처리(吸收機能差異)를 알아보기 위하여 용적밀도(容積密度)와 수분상태(水分狀態)를 달리한 Core에서의 유근신장(幼根伸長)과 용적밀도(容積密度)를 달리하여 pot재배(栽培)하였을 때 근(根)의 총(總)길이와 표면적(表面積), 근반경(根半徑) 및 양분(養分)의 흡수속도(吸收速度)를 조사(調査)한 결과(結果) 다음과 같다. 1. 대두(大豆)의 유근신장(幼根伸長)은 용적밀도(容積密度)가 낮을수록 빨랐으며 양토(壤土)에서는 토양수분(土壤水分) 상태(狀態)가 - 4bar 이하(以下)에서, 사양토(砂壤土)에서는 - 1bar 이하(以下)에서 급격(急激)히 감소(減少)하였다. 2. 유근(幼根)의 신장(伸長)은 ELE경도계(硬度計) 토양강도(土壤强度) 2.0 이상(以上)에서 급격(急激)히 감소(減少)하였으며, 근신장속도(根伸長速度)와 토양강도간(土壤强度間)에는 2차식(次式)으로 표시(表示)되었다. 그러나 사양토(砂壤土)에서 -10bar이하(以下)의 토양수분상태(土壤水分狀態)에서는 경도(硬度)에 관계(關係)없이 근신장속도(根伸長速度)가 낮았다. 3. pot재배시험(栽培試驗) 결과(結果), 뿌리의 총(總)길이는 용적밀도(容積密度)가 $1.2g/cm^3$인 양토(壤土)에서 가장 길었으며, $1.4g/cm^3$인 사양토(砂壤土)에서 가장 짧았다. 세근(細根)의 평균직경(平均直徑)은 사양토(砂壤土)에서 생육(生育)한 것이 양토(壤土)에서 생육(生育)한 것보다 굵었다. 뿌리의 총표면적(總表面積)은 용적밀도(容積密度)가 낮을수록 넓었으며, 양토(壤土)에서 사양토(砂壤土)보다 넓었다. 4. 양분(養分)의 흡수량(吸收量)은 건물생산(乾物生産)이 많은 양토(壤土)에서 많았다. 단위(單位)뿌리표면적당(表面積當) 흡수속도(吸收速度)는 질소(窒素)가 양토(壤土)에서 $597{\sim}753n\;mole/day{\cdot}cm^2$, 사양토(砂壤土)에서 $222{\sim}365n\;mole/day{\cdot}cm^2$이었으며, 용적밀도(容積密度)가 높은 토양(土壤)에서 높은 값을 보였다. K는 $99{\sim}175n\;mole/day{\cdot}cm^2$ P는 $26{\sim}46n\;mole/day{\cdot}cm^2$이었고, Ca와 Mg는 각각(各各) $175{\sim}230n\;mole/day{\cdot}cm^2$, $163{\sim}205n\;mole/day{\cdot}cm^2$의 범위(範圍)를 보였으며 토양간(土壤間)의 차이(差異)는 질소(窒素)보다 적은 경향(傾向)이었다.

• 한국산림과학회지
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• 제76권1호
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• pp.1-10
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• 1987

잣나무의 유묘기(幼苗期) 생육(生育)에 있어 광(光)과 단근(斷根) 처리(處理)에 따른 이식후(移植後) 생장(生長)에 미치는 몇 가지 영향(影響)에 대하여 조사(調査), 비교(比較) 하였다. 기(其) 결과(結果) 묘목(苗木)의 활착율(活着率)은 상대광도(相對光度)가 낮은 19%구(區)가 가장 높았고, 단근량(斷根量)은 1/2 이상(以上)이 되면 50% 이상(以上)이 감소(減少)되었다. 지상부(地上部), 지하부(地下部) 및 묘경생장(苗徑生長)은 상대광도(相對光度) 100%에서, 그리고 단근(斷根) 1/4 처리구(處理區)가 가장 양호(良好)하였다. 또한 엽속수(葉束數) 및 엽면적(葉面積)은 상대광도(相對光度) 63%구(區)가, 그리고 단근(斷根) 1/4 처리구(處理區)가 가장 크게 나타났다. 따라서 잣나무 유묘생장(幼苗生長)에 미치는 광도(光度)의 영향(影響)은 비교적(比較的) 높았으나 단근량(斷根量)의 효과(效果)는 극(極)히 적게 나타났다.

• Journal of Plant Biology
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• 제17권1호
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• pp.9-14
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• 1974

Inhibitory effect of alantolactone and isoalantolactone was shwon in Avena straight growth test and in the formation of adventitious root in Phaseolus seedling. However, di-, and tetrahydroalantolactones given no effect on the elongation and the rooting. Inhibitory effect of alantolactone could partly be removed by cysteine, cystine, and reduced glutthione. The plant materials were made less sensitive to alantolactone by the pretreatment of cysteine, but cysteine supplied after the treatment of alantolactone brought about no effect on the action of alantolactone. A new spot was shown on TLC plate from the mixture of alantolactone and cysteine, indicating that alantolactone can be inactivated by cysteine, not cystine, without any biological processes.