• Korean Journal Plant Pathology
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• v.12 no.3
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• pp.368-373
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• 1996

배나무잎 검은점병에 이병된 신고와 지표식물 PS-95의 잎을 전자현미경으로 세포내 미세구조를 검경한 결과 굴곡성 사상형 유사바이러스 입자가 집단으로 존재하고 있는 것을 확인하였다. 엽육유세포질에 있는 유사바이러스 입자들의 직경은 12 nm였으나 입자들의 길이는 측정하지 못하였다. 섬유사를 함유하고 있는 소포는 일반적으로 ssRNA genome을 갖는 식물바이러스에 의해 이병된 세포에서 생성된다. 본 연구에서 이 소포들은 tonoplast에 형성되었다. 배나무잎 검정점병의 이병잎을 초본 지표식물에 즙액접종하였으나 어떠한 병징도 나타나지 않았다. 또한 접목접종 전염에 의하여 전염되어 전형적인 검은점이 발병하였다. 발병된 잎에는 유사바이러스 입자가 존재하고 있었다. 이상의 결과 병징, 섬유사를 함유한 소포의 존재, 그리고 접목전염을 기초로하여 볼 때 배나무 검은점병을 일으키는 유사바이러스 입자는 closteroviruses의 하나로 생각된다.

• The Korean Journal of Mycology
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• v.11 no.1
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• pp.33-34
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• 1983

흰가루병(病)에 감염(感染)된 괭이밥(Oxalis corniculata L.)을 1982년(年) 6월(月) 수원(水原)에서 다수(多數) 채집(採集)하였다. 병원균(病原菌)의 형태적(形態的) 특징(特徵)을 검경(檢鏡)한 결과(結果), 한국산(韓國産) 미기록(未記錄) 흰가루병균(病菌)인 Oidium oxalidis McAlp.로 동정(同定)되었다. 이병식물(罹病植物)은 10월말경(月末頃) 거의 고사(枯死)하였으며, 이 병원균(病原菌)의 완전세대(完全世代)는 관찰(觀察)되지 않았다.

• Korean journal of applied entomology
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• v.59 no.2
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• pp.113-116
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• 2020

In this study, we report a genus Macrobathra for the first time from Korea, including one newly reported species, M. quercea Moriuti, 1973. Adult including the genitalia of both sexes are described and photographs of adults and genitalia, distributional ranges and host plants are also provided.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.187-198
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• 1988

The second leaves from 30 days old seedlings of two rice cultivars which were selected as tolerant (cv. Chokoto) and susceptible (cv. Weld pally) cultivar were soaked in the concentration of $10^{-6}$, $10^{-5}$, $10^{-4}$ and $10^{-3}M$ of oxyfluorfen for 10, 15 and 22hrs and anatomical characteristics were abserved. Dipping to the solutions were carried out either directly to the attached leaves or to the seperated leaves. Development of any symptoms in epidermis, bundle sheath, mesophyll cells and bulliform cells were microscopically inspected. Both cultivars showed reductionin leaf thickness, but the susceptible ones was more sensitive than the tolerant. The degradation and disappearance of epidermal cell layer, breakage of bundle sheath cells, shrinkage of mesophyll cells and disappearance of bulliform cells were general response as affected by oxyfluorfen treatment. The susceptible cultivars showed such responses at the concentration of $10^{-5}M$ for 10 hrs while tolerant ones $10^{-3}M$, for 10 hrs. Those treatments were more effective in seperated leaves than in attached ones. The epicuticular wax layer of leaves treated as above for 20 hrs was inspected by SEM. Weld pally, the susceptible cultivar (Weld pally) showed rapid cleavage of wax layer under $10^{-5}M$ concentration while the tolerant (Chokoto) showed only minor damage on wax layer at the concentration of $10^{-3}M$.

• Research in Plant Disease
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• v.17 no.2
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• pp.191-195
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• 2011

This experiment was attempted to investigate a cause of the scion death in green pepper grafting system. A tobamovirus particle examined in the rootstock of the sample but not in the scion showing necrosis. The virus isolated from the rootstock was identified as Pepper mild mottle virus (PMMoV), pepper tobamovirus pathotype P1.2. (PMMoV-2), by nucleotide sequence analysis and host plant reaction. The virus isolate infected systematically in 6 commercial rootstock varieties using for green pepper grafting seedling production. Green pepper varieties 'Long green mart' and 'Daechan' represented resistance to the virus showing local lesions only on the inoculated leaves and 'Manitda' was systematically infected. In the experiment with grafting 'Long green mart' or 'Daechan' onto the those rootstocks, the upper leaves of the scions first showed vein necrosis and wilt symptoms 7 days after inoculation with PMMoV-2 on the cotyledon of the rootstock, following to the scion stem necrosis and then only the scion death. The virus was detected in the rootstock but not in the scion. However, 'Manitda' of susceptible variety in the grafting system showed mottle symptom on the leaves of the scion but not necrosis on the plant. PMMoV-3 isolate, pepper tobamovirus pathotype P1.2.3, did not cause the scion death in the grafting system. All of the varieties were susceptible to PMMoV-3. These results suggest that the scion death is caused by infecting with pepper tobamovirus pathotype P1.2. in the green pepper grafting system combined with the susceptible rootstock and the resistance scion to the virus pathotype.

• Research in Plant Disease
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• v.20 no.4
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• pp.307-313
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• 2014

In May 2013, an angel's trumpet leaves showing mosaic and malformation symptoms were collected from Suwon city, Gyeonggi-do. An analysis of the collected sample by transmission electron microscopy observation showed filamentous rod particles of 720-800 nm in length. On the basis of the these observations, we performed PCR against three reported Potyviruses (Brugmansia mosaic virus, Colombian datura virus and Brugmansia suaveolens mottle virus), and the sample was positive for BruMV. Pathogenicity and host range test of BruMV was determined by mechanical inoculation. Solanaceae (tobacco, tomato and eggplant) and Amaranthaceae (ground cherry) appeared typical virus symptoms. To determine coat protein of this virus, we designed specific primer pairs, and performed PCR amplification, cloning, and sequencing. Phylogenetic analysis showed that BruMV-SW was most closely related to BruMV isolate SK. Comparison of the BruMV-SW coat protein nucleotide sequences showed 92% to 99% identities to the other BruMV isolates.

• Korean Journal of Environmental Biology
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• v.36 no.1
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• pp.62-72
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• 2018

In order to provide important information for the efficient management of the identified farm ecosystem in Jinju Bay, we investigated the spatial and temporal distribution of the phytoplankton community using a UPLC pigment analysis and a CHEMTAX program from the timeframe of February 2013 to January 2014. In addition, we measured the available physical and chemical parameters controlling the distribution of the phytoplankton communities. As a result of this comprehensive pigment analysis, it was noted that the Diatoms were the predominant species with an average of 77.1% as noted located in Jinju Bay. It was discovered that during the summer season, the phytoplankton community composition was changed by a reduction of diatoms and noted increases of the Cryptophytes, Prasinophytes, and Dinoflagellates. Especially, it was noted that the Cryptophytes and Prasinophytes were shown with an average of 18.8% and 17.8% in June, respectively. However, it was revealed that the Cryptophytes and Prasinophytes were not shown by a microscopic observation. The phytoplankton community composition was correlated with the temperature and salinity variations as noticed in the Jinju Bay. Therefore, the water temperature and freshwater inputs in the Jinju Bay were important environmental factors for controlling the phytoplankton community composition and the varying Cryptophytes and the noted amounts of Prasinophytes as well.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.219-236
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• 1988

Bensulfuron concentrations of $10^{-7}$, $10^{-6}$, $10^{-5}$ and $10^{-4}M$ were applied to agar medium on susceptible (cv. KH 17854 and cv. IR 1846) and tolerant (cv. Chinsurah Boro II and IR 14252) rice cultivars were grown for microscopic inspection. Susceptible cultivars showed the decrease in shoot and root growth at the concentration of $10^{-5}M$ while ones showed no difference. Such a tendency was also observed from microscopic inspection in the elongation zone of shoot meristematic tissue. Seedlings grown in soil for 10 days were transfered to distilled water containing only bensulfuron solutions. There were significant differences between cultivars in terms of supression of shoot meristematic activity and swelling of cell volume. Observations of those cells made it clear that especially susceptible cultivars showed the irregular cell layering, vacuolation, cell swelling and partial damage in membrane of shoot tissue. The major response of root tips of susceptible cultivars showed the disorganization of cortex, rupture and contraction of membrane, inhibition of cell division, swelling and emergence of lateral root while tolerant ones showed no such responses.

• Journal of Korea Water Resources Association
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• v.56 no.6
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• pp.373-380
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• 2023

Due to abnormal climate phenomena and climate change in Korea, overgrowth of algae in rivers and reservoirs occurs frequently. Algae in rivers are classified into green algae, blue-green algae, diatom, and other types, and some species of blue-green algae cause problems due to odor and the discharge of toxic substances. In Korea, an algae alert system is in place, and it is issued based on the number of harmful blue-green algae cells. Thus, measuring harmful blue-green algal blooms is very important, and currently, the analysis method of algae involves taking field samples and determining the cell count of green algae, blue-green algae, and diatoms through algal microscopy, which takes a lot of time. Recently, the analysis of algae concentration through Phycocyanin, an alternative indicator for the number of harmful algae cells, has been conducted through remote sensing. However, research on the analysis of the number of blue-green algae cells is currently insufficient. In this study, we water samples for algal analyses were collected from river and counted the number of blue-green algae cells using algae microscopy. We also obtained the Phycocyanin concentration using an optical sensor and acquired algae spectra through a hyperspectral sensor. Based on this, we calculated the equation for estimating blue-green algae cell counts and estimated the number of blue-green algae cells.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.21 no.1
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• pp.44-47
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• 2016

Real-time PCR was applied to early warning of red tide. For early warning of red tide at $10cells\;mL^{-1}$, Cochlodinium polykrikoides specific real-time PCR was used as a complement of microscopy that has a lower detection sensitivity. C. polykrikoides appeared extensively in Tongyeong, Namhae waters at low densities in the end of June, and early warning of C. polyrkrikoides blooms was issued on 2 August 2015.