• 제목/요약/키워드: yellow leaves

검색결과 301건 처리시간 0.031초

PHYSIOLOGICAL RESPONSE OF PANAX GINSENG TO LIGHT

  • Park Hoon
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 1980년도 학술대회지
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    • pp.151-170
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    • 1980
  • Physiological response of Panax ginseng var. atropurpureacaulo (purple stem variety, Pg) to light was reviewed through old literatures and recent experiments. Canopy structure, growth, pigment, leaf anatomy, disease occurence, transpiration, photosynthesis (PS), leaf saponin, photoperiodism and nutrient uptake were concerned. P. ginseng var. xanthocarpus (yellow berry variety, Px) and Panax quinquefolius(Pq) were compared with Pg if possible. Compensation point(Cp) increased with increase of light and ranged from 110 to 150 at $20^{\circ}C$ but from 140 to 220 at $30^{\circ}C$ with 4 to 15 Klux indicating occurence of light and temperature-dependent high photorespiration. Characteristics of Korea ginseng to hate high temperature was well accordance with an observation 2000 years ago. Korea ginseng showed lower Cp and appeared to be more tolerant to high light intensity and temperature than American sheng although the latter showed greater PS, stomata frequency and conductance, chlorophyll and carotenoids. Px showed lower PS than Pg probably due to higher Cp. Total leaf saponin was higher in leaves grown under high light. Ratio or diol saponin and triol saponin(PT/PD) decreased with increase of light intensity during growing mainly due to decrease of ginsenoside $Rg_1$ but increase of ginsenoside Rd. Leaves of Pg and Px had $Rg_1$ but no $Rb_3$ which was only found as much as $20\%$ of total in Pq leaves, and decreased with increase of light intensity. Re increased in Pg and Px but decreased in Pq with increase of light. PT/PD in leaf ranged 1.0-1.5 in Pg and Px but around 0.5 in Pq. Korea ginseng has Yang characteristics(tolerant to high light and temperature), cultured under Eum(shade) condition and long been used for Yang efficacy (to build up energy) while Pq was quite contrary. Traditional low light $intensity(3-8\%)$ for Korea ginseng culture appeared to be strongly related to historical unique quality. Effect of light quality and photoperiodism was not well known. Experiences are long but scientific knowledge is short for production and quality assessment of ginseng. Recent scientific knowledge of ginseng should learn wisdom from old experiences.

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Identification and Characterization of Xanthomonas arboricola pv. juglandis Causing Bacterial Blight of Walnuts in Korea

  • Kim, Hyun Sup;Cheon, Wonsu;Lee, Younmi;Kwon, Hyeok-Tae;Seo, Sang-Tae;Balaraju, Kotnala;Jeon, Yongho
    • The Plant Pathology Journal
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    • 제37권2호
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    • pp.137-151
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    • 2021
  • The present study describes the bacterial blight of walnut, caused by Xanthomonas arboricola pv. juglandis (Xaj) in the northern Gyeongbuk province, Korea. Disease symptoms that appear very similar to anthracnose symptoms were observed in walnut trees in June 2016. Pathogens were isolated from disease infected leaves, fruits, shoots, bud, flower bud of walnut, and cultured onto yeast dextrose carbonate agar plates. Isolated bacteria with bacterial blight symptoms were characterized for their nutrient utilization profiles using Biolog GN2 and Vitek 2. In addition, isolates were subjected to physiological, biochemical, and morphological characterizations. Furthermore, isolates were identified using 16S rDNA sequence analysis, and multi-locus sequence analysis using atpD, dnaK, efp, and rpoD. To confirm pathogenicity, leaves, fruits, and stems of 3-year-old walnut plants were inoculated with bacterial pathogen suspensions as a foliar spray. One week after inoculation, the gray spots on leaves and yellow halos around the spots were developed. Fruits and stems showed browning symptoms. The pathogen Xaj was re-isolated from all symptomatic tissues to fulfill Koch's postulates, while symptoms were not appeared on control plants. On the other hand, the symptoms were very similar to the symptoms of anthracnose caused by Colletotrichum gloeosporioides. When walnut plants were inoculated with combined pathogens of Xaj and C. gloeosporioides, disease symptoms were greater in comparison with when inoculated alone. Xaj population size was more in the month of April than March due to their dormancy in March, and sensitive to antibiotics such as oxytetracycline and streptomycin, while resistant to copper sulfate.

Fine Mapping of Zenith Derived Rice Stripe Virus Resistance Gene, Stv-b

  • Sais-Beul Lee;Jun-Hyun Cho;Nkulu Rolly Kabange;Sumin Jo;Ji-Yoon Lee;Yeongho Kwon;Ju-Won Kang;Dongjin Shin;Jong-Hee Lee;You-Cheon Song;Jong-Min Ko;Dong-Soo Park
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2020년도 추계국제학술대회
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    • pp.63-63
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    • 2020
  • Rice stripe virus (RSV) disease is one of the major constraints in rice production, transmitted by the small brown planthopper (SBPH; Laodelphax striatellus). Upon RSV infection, plants develop typical symptoms, which include chlorosis and weakness of newly emerged leaves, white and yellow spots, stripe on leaves, and necrotic and wilting leaves, resulting in plant growth inhibition, oxidative damage that may culminate in programmed cell death (PCD) and plant death in severe epidemics. Although RSV-resistant quantitative trait loci (QTLs), Stv-a, Stv-b, and Stv-bi, were mapped using various resistant varieties, one RSV-resistant gene, OsSOT1, has been identified so far. In this study, we used the rice cultivar Zenith, known to carry Stv-b, to investigate novel RSV-genes through fine mapping. Therefore, we crossed Zenith (Donor parent, RSV resistant) with Ilpum (Recurrent parent, RSV susceptible) to fine-map using a BC2F2 population of 2100 plants. Chromosome segment introgression lines that were heterozygous at a different region were selected, two types of heterozygous lines showed an heterozygous genotype between Sid2 and Sid75 to Indel9 and RM6680. Interestingly, we identified qSTV11Z region harboring Stv-b, covering about 171-kb region between the InDel markers Sid75 and Indel8. The localization of qSTV11Z provides useful information that could be used for marker-assisted selection and determination of genetic resources in rice breeding.

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감관총채벌레(Ponticulothrips diospyrosi)의 분포와 발생소장 (Distribution and Seasonal Occurrence of Japanese Gall-forming Thrips, Ponticulothrips diospyrosi, in Korea)

  • 허완;허혜순;윤지은;손준기;장현규;엄기백;박정규
    • 한국응용곤충학회지
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    • 제45권1호
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    • pp.59-66
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    • 2006
  • 전국의 감 재배 농가를 대상으로 감관총채벌레(Ponticulothrips diospyrosi Haga et Okajima)의 피해 면적과 분포 및 방제방법을 설문 조사하였고, 경남 김해와 진주의 세 곳 단감원에서 끈끈이 트랩과 감관총채벌레에 의한 피해엽을 조사하여 각 태별 발생시기를 파악하였으며, 트랩의 위치와 트랩면의 방향에 따른 유살수의 차이를 비교하였다. 감관총채벌레는 단감뿐 아니라 떫은 감도 가해하였으며, 피해면적은 2000년 이후 급격히 증가하여 2005년에는 전국적으로 446 ha에 달하였는데, 피해면적은 경남>경북>전남 순이었다. 대부분의 농민들은 감관총채벌레를 방제하기 위하여 살충제를 살포하거나 피해 잎을 제거해주었다. 월동세대와 제1세대 성충은 각각 5월 중순과 6월 상 중순부터 피해엽내에서 관찰되었으며, 7월 중순 이후에는 피해엽 내에 감관총채벌레가 발견되지 않았다. 황색끈끈이 트랩에 의한 월동세대 성충의 유살최성기는 5월 중순이었고, 제1세대 성충의 유살최성기는 김해에서는 6월 중 하순, 진주에서는 6월 하순이었다. 과수원 중앙보다는 외곽에 설치한 트랩에 제1세대 성충이 더 많이 유인되었으나 유살시기에는 차이가 없었다. 끈끈이 판의 양면 중에서 과수원의 중앙보다는 소나무 숲으로 향한 면에 더 많은 성충이 유살되는 경향이 있었으나 통계적 차이는 없었다.

삽목묘의 묘령이 장미의 생장과 수량에 미치는 영향 (Growth and Cut Flower Yield of Roses as Affected by Age of Rooted Cuttings)

  • 박유경;정병룡
    • 화훼연구
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    • 제19권1호
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    • pp.8-14
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    • 2011
  • 본 연구는 두 품종의 장미 삽목묘의 묘령에 따른 생장과 수량에 미치는 영향을 조사하고 국내 육성 절화장미의 효과적인 삽목번식법을 개발하고자 수행하였다. 장미는 스탠다드 계통인 'Pink Aurora'와 스프레이 계통인 'Yellow King' 품종을 사용하였다. 삽수는 5매엽을 사용하였고 서로 다른 날짜에 암면큐브($5cm{\times}5cm{\times}5cm$, UR, 한국)에 삽목하였다. 2009년 1월 20일에 삽목하여 30일이 경과한 삽목묘와 2009년 1월 2일에 삽목하여 48일이 경과한 묘를 사용하여 2009년 4월 18일에 암면슬래브($10cm{\times}15cm{\times}100cm$, UR, 한국)에 정식하였다. 2009년 1월부터 7월까지 재배하는 동안에 2번 수확하여 절화의 품질을 조사하였다. 정식전의 생육을 조사한 결과 48일이 경과한 묘는 두 품종 모두 신초와 뿌리가 생장하였다. 그러나 30일이 경과한 묘는 'Pink Aurora'의 경우 신초와 뿌리가 생장하지 않았고, 'Yellow King'은 신초는 생장하였고 뿌리는 생장하였으나 배지에서 육안으로 확인할 수 없었다. 이러한 결과로 'Yellow King'이 'Pink Aurora'보다 생장속도가 빠른 것으로 판단된다. 정식 후의 생장과 절화 수량은 스탠다드 계통인 'Pink Aurora'는 30일 경과한 묘보다 48일이 경과한 묘에서 수량이 더 많이 나타났지만, 평균 절화 생체중은 30일이 경과한 묘보다 작았다. 'Yellow King' 품종은 30일이 경과한 묘에서 절화장, 화폭, 5매엽수, 절화 생체중, 수량이 40일 경과한 묘보다 더 높았다. 'Pink Aurora' 품종은 48일이 경과한 묘에서 다른 처리에 비해 더 좋은 생육을 보였다. 'Yellow King' 품종은 뿌리의 상처가 작았던 30일이 경과한 묘에서 더 높은 수량을 보였다. 이러한 결과는 품종에 따른 성숙도의 차이로 판단되며 다양한 품종을 대상으로 한 실험이 필요하다고 생각된다.

Constituents of the Essential Oil from Eclipta prostrata L.

  • Chang, Kyung-Mi;Kim, Gun-Hee
    • Preventive Nutrition and Food Science
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    • 제14권2호
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    • pp.168-171
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    • 2009
  • The volatile aroma constituents of Eclipta prostrata L. (leaves, stems, and flowers) were isolated by hydro-distillation extraction method and analyzed by GC/MS. The yield of Eclipta prostrata L. essential oil was 0.1% (v/w), and its color was yellow. Sixty-eight volatile flavor compounds, which make up 71.15% of the total volatile composition of the essential oil were tentatively characterized. It contained 35 hydrocarbons (56.25%) with sesquiterpene predominating, 12 alcohols (3.05%), 8 ketones (3.83%), 9 aldehydes (1.86%), 2 oxides (6.03%), and 2 esters (0.13%). ${\alpha}$-Humulene, 6,9-heptadecadiene, (E)-${\beta}$-farnesene, and ${\alpha}$-phellandrene were the major abundant aroma components in Eclipta prostrata L., aromatic and medicinal plant.

First Report on Carnation vein mottle virus in Dianthus barbatus in Korea

  • Chung, B.N.;Kim, B.D.;Choi, G.S.;Kim, J.S.
    • The Plant Pathology Journal
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    • 제20권3호
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    • pp.224-228
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    • 2004
  • A potyvirus causing chlorotic mottle and yellow spots on leaves of Dianthus barbatus was isolated and identified as an isolate of Carnation vein mottle virus (CVMV). Purified preparations of Chenopodium quinoa infected with CVMV-K showed filamentous particles between 695 and 785 om long. Many cytoplasmic inclusions were observed, and these consisted of pinwheels, dense bands, loops, and circles. The coat protein of CVMV-K was about 32 KDa in western blot analysis using a CVMV antibody. The nucleotide sequence of coat protein gene showed 97.6% homology with a Japanese isolate. The genome size of CVMV-K was about 9.0 kb by dsRNA analysis. These results indicate that the virus is an isolate of CVMV. This is the first report on CVMV in Korea.

Outbreak of Rust Caused by Coleosporium asterum on Solidago virgaurea var. gigantea in Ulleung-do

  • Back, Chang-Gi;Nam, Gu-Youn;Lee, Seung-Yeol;Jung, Hee-Young
    • Mycobiology
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    • 제42권1호
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    • pp.79-81
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    • 2014
  • From June to October 2012, severe outbreaks of rust disease on Solidago virgaurea var. gigantea were observed in 5 different regions of Ulleung-do, Korea. Typical rust symptoms appeared as yellow spots, uredinia on leaves, and massive urediniospores covering the entire plant. Severely infected plants became discolored and died. On the basis of its morphological and molecular characteristics, the causal agent was identified as Coleosporium asterum. This pathogen has been reported as rust disease on S. virgaurea in the Canada and United States. In Korea, rust disease on S. virgaurea var. gigantea was reported as Uromyces rudbeckia in 1992. To the best of our knowledge, C. asterum is a novel rust pathogen on S. virgaurea var. gigantea in Korea.

Association of Aster Yellow Phytoplasma with Witches′ Broom Disease of Ash(Fraxinus rhynchophylla Hence) in Korea

  • Sangsub Han;Lim, Tae-Heon;Byeongjin Cha
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.73.2-73
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    • 2003
  • Typical whiches broom symptoms caused by phytoplasma were observed in Ash (Fraxinus rhynchophylla Hence) in Korea. The symptoms were showing abnormally small leaves, short internodes, and proliferation of shoots. Fluorescence and electron microscopy of leaf midribs revealed phytoplasma positive DAPI fluorescence and numerous phytoplasma bodies localized in the phloem sieve tubes. Phytoplasma DNA of 1.8 Kb was detected consistently from all symptomatic samples by the amplification of phytoplasma DNA with the phytoplasma specific primer pair Pl/P7. But no phytoplasma DNA was detected in healthy ash seedlings. Based on sequence analyses of an amplified region, this phytoplasma is closely related to Eqilodium phyllody, Mulberry dwarf, and Aster yellows phytoplasmas with the homology of 99.95 %, 99.79 % and 99.78 %, respectively, This phylogenetic analyses indicate that ash witches broom phytoplasma but is evidently distinct from the ash yellows group 16SrⅦ and should be classified into the Aster yellows group 16SrⅥ.

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Oidiopsis taurica (L v.) Arnaud (=Leveillula taurica)에 의한 토마토 흰가루병 발생 (Occurrence of Powdery Mildew on Tomato Caused by Oidiopsis taurica (L v.) Arnaud (=Leveillula taurica) in Korea)

  • 강수웅;권진혁;신원교;김희규
    • 한국식물병리학회지
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    • 제11권4호
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    • pp.380-382
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    • 1995
  • Yellow spot or blotch symptoms on the upper surface of leaf, without the production of velvet-like fungi on the lower surface of leaf as in the gray mold of tomato caused by Cladosporium fulvum, were observed in tomato (cv. Seokwang) plants in May, 1995, in a vinyl-house of the experimental plot of Gyeongnam Provincial Rural Development Administration, Chinju, Gyeongnam, Korea. We identified this disease as powdery mildew of tomato caused by Oidiopsis taurica (L v.) Arnaud (=Leveillula taurica), which was new to Korea. Conidia of the fungus were borne on uni- or bi-septated conidiophores which were developed through the stomata of the tomato leaf. The conidia were slender, clavate and variable in size (31~111.6$\times$13.1 ${\mu}{\textrm}{m}$). The fungal conidia isolated from tomato leaves were inoculated to tomato plants, and the occurrence of the same disease was confirmed based on the symptomatology and the morphology of the pathogen reisolated.

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