• 제목/요약/키워드: Yellowing

검색결과 260건 처리시간 0.031초

인삼의 생리장해 (Physiological disorder of Panax ginseng)

  • 박훈
    • 한국작물학회지
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    • 제36권5호
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    • pp.459-480
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    • 1991
  • 인삼의 생리장해를 산지중심으로 증상별로 종합검토하였다. 뿌리의 장해는 적피, 은피, 동해, 동해, 근부, 안삼, 출아불재, 달래삼, 소수가 있고 지상부에는 황엽, 조기낙엽, 소엽, 지엽, 백반엽, 동해, 풍해와 경열이 있다. 적피와 황엽이 인삼생산에 가장 크게 영향한다. 농약해, 붕소과 잉해 및 산업공해에 의한 피해 경우도 보고되었다. 원료수삼 가공한 후의 품질요인에 관계되는 생리장해들도 검토하였다.

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Little Leaf and Yellowing Symptoms on Castanea crenata are Associated with Phytoplasma in Korea

  • Eun Ju Cheong
    • Journal of Forest and Environmental Science
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    • 제39권1호
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    • pp.49-54
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    • 2023
  • For unknown reasons, a few trees in a private chestnut orchard in Icheon si, Gyunggi-do suffered leaf chlorosis and growth decline. Based on symptoms, phytoplasma was a probable cause. Leaf samples were collected from two symptomatic and non-symptomatic trees in the orchard for phytoplasma detection. An amplicon of about 1.2 bp size was obtained from both symptomatic trees by PCR with the universal 16S rDNA primers. Sequences of these amplicons were found to have 99% nucleotide sequence identity to the corresponding genomic region of 16SrIII (X-disease group). More than 100 phytoplasma isolates, such as Candidatus phytoplasma pruni, Milkweed yellows phytoplasma, Goldenrod yellows phytoplasma, Tsuwabuki witches'-broom phytoplasma, Candidatus Phytoplasma trifolii, etc. were involved in the list. Phylogenetic analysis revealed that the sequence obtained in this study closely clustered with Candidatus phytoplasma groups. While one of the amplicons shared 91% identity with the Candidatus phytoplasma castaneae, the other shared only 47%. It needs further analysis and investigation to determine the exact taxonomy. Meanwhile, based on the analysis of the sequences, chlorosis, and small leaves were associated with phytoplasma.

총생 증상을 보이는 한국잔디로부터 노균병원균 관찰 (Observation of Scleropthora macrospora Causing Downy Mildew from Zoysiagrass with Leaf Yellowing and Excessive Tillering)

  • 한무호;김경덕;피재호;최수민;박대섭
    • Weed & Turfgrass Science
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    • 제5권1호
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    • pp.23-28
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    • 2016
  • 전국적으로 재배중인 한국잔디에서 확대되고 있는 총생잔디에서 현미경을 이용하여 피시움균의 난포자와 유사하지만 다소 큰 사이즈인 $50{\sim}80{\mu}m$의 난포자를 관찰하였다. 동일 시료들을 암상태의 저온 다습한 조건에서 24시간 증식한 후 현미경으로 관찰한 결과 $80{\sim}100{\mu}m$ 크기의 Sclerophthora macrospora 유주자낭이 확인되었다. 유전자 분석을 통한 확인을 위해 유전자 은행에 등록된 S. macrospora 염기서열 정보를 바탕으로 제작된 프라이머와 감염된 조직에서 추출한 DNA로 PCR 후, S. macrospora 특이적인 밴드가 증폭되는 것을 알 수 있었다. 이러한 결과로 S. macrospora가 한국잔디 총생 증상에 관여하는 가능성이 있을 것으로 사료된다.

Biological and Molecular Characterization of a Korean Isolate of Cucurbit aphidborne yellows virus Infecting Cucumis Species in Korea

  • Choi, Seung-Kook;Yoon, Ju-Yeon;Choi, Gug-Seoun
    • The Plant Pathology Journal
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    • 제31권4호
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    • pp.371-378
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    • 2015
  • Surveys of yellowing viruses in plastic tunnels and in open field crops of melon (Cucumis melo cultivar catalupo), oriental melon (C. melo cultivar oriental melon), and cucumber (C. sativus) were carried out in two melon-growing areas in 2014, Korea. Severe yellowing symptoms on older leaves of melon and chlorotic spots on younger leaves of melon were observed in the plastic tunnels. The symptoms were widespread and included initial chlorotic lesions followed by yellowing of whole leaves and thickening of older leaves. RT-PCR analysis using total RNA extracted from diseased leaves did not show any synthesized products for four cucurbit-infecting viruses; Beet pseudo-yellows virus, Cucumber mosaic virus, Cucurbit yellows stunting disorder virus, and Melon necrotic spot virus. Virus identification using RT-PCR showed Cucurbit aphid-borne yellows Virus (CABYV) was largely distributed in melon, oriental melon and cucumber. This result was verified by aphid (Aphis gossypii) transmission of CABYV. The complete coat protein (CP) gene amplified from melon was cloned and sequenced. The CP gene nucleotide and the deduced amino acid sequence comparisons as well as phylogenetic tree analysis of CABYV CPs showed that the CABYV isolates were undivided into subgroups. Although the low incidence of CABYV in infections to cucurbit crops in this survey, CABYV may become an important treat for cucurbit crops in many different regions in Korea, suggesting that CABYV should be taken into account in disease control of cucurbit crops in Korea.

Computer Simulation for Gradual Yellowing of Aged Lens and Its Application for Test Devices

  • Kim, Bog G.;Han, Jeong-Won;Park, Soo-Been
    • Journal of the Optical Society of Korea
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    • 제17권4호
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    • pp.344-349
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    • 2013
  • This paper proposes a simulation algorithm to assess the gradual yellowing vision of the elderly, which refers to the predominance of yellowness in their vision due to aging of the ocular optic media. This algorithm employed the spectral transmittance property of a yellow filter to represent the color appearance perceived by elderly people with yellow vision, and modeled the changes in the color space through a spectrum change in light using the yellow filter effect. The spectral reflectivity data of 1269 Munsell matte color chips were used as reference data. Under the standard conditions of a D65 illuminant and a $10^{\circ}$ observer of 1964 CIE, the spectrum of the 1269 Munsell colors were processed through the yellow filter effect to simulate yellow vision. Various degrees of yellow vision were modeled according to the transmittance percentage of the yellow filter. The color differences before and after the yellow filter effect were calculated using the DE2000 formula, and the color pairs were selected based on the color difference function. These color pairs are distinguishable through normal vision, but the color difference diminishes as the degree of yellow vision increases. Assuming 80% of yellow vision effect, 17 color pairs out of $(1269{\times}1268)/2$ pairs were selected, and for the 90% of yellow vision effect, only 3 color pairs were selected. The result of this study can be utilized for the diagnosis system of gradual yellow vision, making various types of test charts with selected color pairs.

Micro Shell을 이용한 철기 문화재 복원용 충전제의 사용성 연구 (A Study of Usability of Micro Shell as a Filler for Restoration of Iron Objects)

  • 이현지;위광철
    • 박물관보존과학
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    • 제27권
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    • pp.91-102
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    • 2022
  • 철기 문화재 복원에 사용되고 있는 실리카 계열의 무기질 충전제는 열팽창률감소, 흐름성 개선 등의 기능성 부여를 목적으로 사용되고 있다. 그러나 충전제의 양이 많을 수록 복원재의 물성저하 및 황변 현상 촉진의 원인이되며, 결과적으로 재처리로 이어져 유물의 피로도를 상승시키는 결과를 초래한다. 따라서 복원제와 충전제의 혼합 정량화 및 황변성 연구 필요성이 강조될 수 밖에 없다. 이를 보완하기 위해 실리카계 경량 충전제인 Micro Shell을 비교군으로 물성연구를 진행하였다. 실험 결과 기존에 사용하던 충전제에 비해 Micro Shell이 황변도 발생 수치가 최대 34% 낮았으며, 충전제의 배합양에 따라서 공통적으로 접착력과 비중의 물성 수치값이 좋은 것을 확인하였다. 본 연구 결과 Micro Shell의 사용 가능성에 대해 확인하였다.

재래종 대두의 갈문병 저항성에 관한 연구 (Studies on Resistance to Septoria Brown Spot(Septoria glycines Hemmi) in Native Soybean Collection)

  • 권신한;오정행;김재리
    • 한국작물학회지
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    • 제25권1호
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    • pp.47-53
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    • 1980
  • 대두 갈문병에 대한 저항성 인자원을 개발하기 위하여 수집재래종대두의 저항성을 검정하고 낙엽률과 수량구성형질간의 관계를 구명한 결과를 다음과 같이 요약하였다. 1. 본시험에 공시한 수집재래종대두 1428계통의 약60% 이상이 심한 황변현상과 조기낙엽에 이르는 가장 높은 리병성 반응(리병지수 5)을 보였으며 약 9%인 136계통은 병반은 형성하나 병반 주위조직의 황변현상이 나타나지 않았으며 이들의 대부분은 녹색종피 계통이었다. 2. 대두 갈문병의 접종시기는 제2~3 복엽기가 효과적이었으며 신엽보다는 성엽에서 병의 진전속도가 빨 간다. 3. 대두 갈문병의 접종 4주 후에 조사한 초생단업의 낙엽률은 비접종구에 비해 약 82% 증가하였으며 황변현상이 나타나지 않는 연색종피 계통과 황변환상을 나타내는 품종간에 차이가 없는 것으로 보아 이들 연색종피 계통을 저항성으로 간징하기는 어려웠다. 4. 대두의 조기낙엽은 초장과 분지수에는 영향이 없었으나 절수, 협수 및 백립중에는 유의성 있는 부의 상관을 보임으로서 수량감소의 중요한 요인이 될것으로 보였다.

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Influence of basal medium formulations and silver nanoparticles on in vitro plant growth in gerbera

  • Hyun Hee Kang;Aung Htay Naing;Junping Xu;Mi Young Chung;Su Young Lee;Jeung-Sul Han;Chang Kil Kim
    • Journal of Plant Biotechnology
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    • 제50권
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    • pp.183-189
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    • 2023
  • This study investigated the impact of two distinct MS basal media: one containing FeNaEDTA and the other FeEDDHA, on the growth of five unique gerbera cultivars (Shy Pink, Pink Holic, Breeze, Harmony, Snow Dream). Notably, the response to these media types varied significantly among the cultivars, particularly concerning leaf yellowing and plant growth. 'Shiny Pink' and 'Pink Holic' exhibited leaf yellowing on the FeNaEDTA-containing medium but displayed leaf greening on the FeEDDHA-containing medium. In contrast, 'Snow Dream,' 'Harmony,' and 'Breeze' remained unaffected on both medium types. However, the FeNaEDTA-containing medium promoted higher plant height and petiole length in 'Breeze,' 'Harmony,' and 'Snow Dream' than the FeNaEDTA-containing medium did. A promotive effect of silver nanoparticles (AgNPs) on plant growth and leaf greening was observed in 'Pink Holic,' particularly on the FeNaEDTA-containing medium, while the addition of AgNPs to the FeEDDHA-containing medium negatively affected plant growth. These results highlight the substantial influence of medium type, specifically the presence of FeNaEDTA or FeEDDHA, on gerbera growth responses, emphasizing the critical role of medium selection in gerbera propagation. Additionally, when contemplating the addition of AgNPs for in vitro gerbera propagation, it is crucial to consider the medium type.

Root Rot of Moth Orchid Caused by Fusarium spp.

  • Kim, Wan-Gyu;Lee, Byung-Dae;Kim, Woo-Sik;Cho, Weon-Dae
    • The Plant Pathology Journal
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    • 제18권4호
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    • pp.225-227
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    • 2002
  • Moth orchid plants with yellowing blight and root rot symptoms were collected, and a total of 54 isolates of Fusarium spp. was obtained from roots and leaf bases of the diseased plants. The isolates were identified based on their morphological characteristics. Out of the 54 isolates of Fusarium spp., 42 isolates were identified as F. solani, 5 isolates as F. oxysporum, and 7 as F. proliferatum. Isolates of the three Fusarium spp. were tested for pathogenicity to moth orchid plants by artificial inoculation. All the Fusarium spp. induced root rot of the host plants. The symptoms progressed up to the basal part of the leaves, which later caused yellowing blight. The symptoms induced on the plants by artificial inoculation with the Fusarium spp. isolates were similar to those observed in greenhouses. The present study reveals that F. oxysporum, F. proliferatum, and F. solani cause root rot of moth orchid, and that F. solani is the main pathogen of the disease.