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Hughes, Karen W. - One of the best experts on this subject based on the ideXlab platform.

Petersen, Ronald H. - One of the best experts on this subject based on the ideXlab platform.

Da Costa, Junet F. - One of the best experts on this subject based on the ideXlab platform.

  • Komparasi Morfologi Beberapa Koloni Jamur Akar Putih (Rigidoporus Microporus) Dari Perkebunan Karet Di Jawa Tengah Dan Sumatera Selatan
    Indonesian Rubber Research Institute, 2018
    Co-Authors: Im Toy, Binerd Anthon, Langkuin J. F., Karwur F. F., Setyawan B., Rondonuwu F. S., Martosupono M., Da Costa, Junet F.
    Abstract:

    Rigidoporus microporus adalah jamur yang menyebabkan penyakit jamur akar putih (JAP) pada tanaman karet. Tingkat keparahan penyakit yang ditimbulkan oleh JAP berbeda antar wilayah. Penelitian ini bertujuan untuk mengetahui komparasi morfologi beberapa koloni jamur akar putih dari perkebunan karet di Jawa Tengah dan Sumatera Selatan. Sampel dikoleksi langsung dari perkebunan Merbuh dan Blimbing di Jawa Tengah dan Balai Penelitian Karet Sembawa di Sumatera Selatan. Penelitian dilakukan pada bulan November 2016-April 2017 di Laboratorium Carotenoid Antioxidant Research Center (CARC) Universitas Kristen Satya Wacana, Salatiga. Hasil yang diperoleh menunjukkan bahwa kecepatan pertumbuhan ke-17 isolat berdasar penambahan diameter koloni hingga mencapai tepi petri bervariasi yaitu 4 hari (MB8), 6 hari (MM6), 7 hari (MK2, MK3, SS1), 8 hari (MK1, MM5, MM7, SS2, SS3), 9 hari (BW1, SS5), 10 hari (MK4, BW4, SS4), 11 hari (BW2), dan 13 hari (BB3). Morfologi koloni dan hifa JAP baik dari Jawa Tengah maupun Sumatera Selatan hampir sama, yakni koloni berbentuk bulat, filamentous, elevasi ada yang rata (flat) dan ada yang sedikit timbul (raised), serta berwarna putih hingga putih gading. Hifa JAP memiliki septa, hialin, bercabang, dan tidak ada Clamp Connection

Binerd Anthon Im Toy - One of the best experts on this subject based on the ideXlab platform.

  • Komparasi Morfologi Beberapa Koloni Jamur Akar Putih dari Perkebunan Karet di Jawa Tengah dan Sumatera Selatan
    Magister Biologi Program Pascasarjana UKSW, 2017
    Co-Authors: Binerd Anthon Im Toy
    Abstract:

    Tidak diizinkan karya tersebut diunggah ke dalam aplikasi Repositori Perpustakaan Universitas.Jamur akar putih (Rigidoporus microporus) adalah jamur yang menyebabkan penyakit jamur akar putih (JAP) pada tanaman karet.Tingkat keparahan penyakit yang ditimbulkan oleh JAP berbeda antar wilayah. Penelitian ini bertujuan untuk mengetahui komparasi morfologi beberapa koloni jamur akar putih dari perkebunan karet di Jawa Tengahdan Sumatera Selatan. Penelitian dilakukan pada bulan November 2016-April 2017 di Laboratorium Carotenoid Antioxidant Research Center (CARC) Universitas Kristen Satya Wacana, Salatiga. Hasil yang diperoleh menunjukkan bahwa kecepatan pertumbuhan ke-17 isolat melalui penambahan diameter koloni hingga mencapai tepi petri bervariasi yaitu 4 hari (MB8), 6 hari (MM6), 7 hari (MK2, MK3, SS1), 8 hari (MK1, MM5, MM7, SS2, SS3), 9 hari (BW1, SS5), 10 hari (MK4, BW4, SS4), 11 hari (BW2), dan 13 hari (BB3). Morfologi koloni dan hifa JAP baik dari Jawa Tengah maupun Sumatera Selatan menunjukkan kesamaan, yakni koloni berbentuk bulat, filamentous, elevasi ada yang rata (flat) dan ada yang tidak rata/timbul (raised), serta berwarna putih hingga putih gading, sedangkan hifa berbentuk hialin, bercabang, memiliki septa, dan tidak ada Clamp Connection.White root rot (Rigidoporus microporus) is a kind of fungi that causes white rot root disease on rubber plant. Level of destruction caused by white root is quite different among areas. This study is aimed to find out the comparation of R. microporus morphology among all R. microporus isolated from from rubber plantation in Central Java and South Sumatera. The study started in November 2016 until April 2017 at Carotenoid Antioxidant Research Center (CARC) Laboratory, Satya Wacana Christian University, Salatiga. The result showed that growth rate of colony diameter of 17 isolates were varied, namely 4 days (MB8), 6 days (MM6), 7 days (MK2, MK3, SS1), 8 days (MK1, MM5, MM7, SS2, SS3), 9 days (BW1, SS5), 10 days (MK4, BW4, SS4), 11 days (BW2), dan 13 days (BB3). Colony and hyphae morphology of all isolates which were isolated from central Java or South Sumatera showed similarity among them. Morphology of R. microporus colony are round, filamentous, flat and raised, and white to ivory colour, whereas its hyphae had septa, hyline, with no Clamp Connection

Jinhyeuk Kwon - One of the best experts on this subject based on the ideXlab platform.

  • morphological and molecular characterization of sclerotium rolfsii teleomorph athelia rolfsii associated with sclerotium rot of cucumis melo l var makuwa makino
    Journal of Agriculture and Life Science, 2017
    Co-Authors: Jinhyeuk Kwon, Dong-wan Kang, Inyoung Han, Changki Shim, Jinwoo Kim
    Abstract:

    In the present study, a severe outbreak of Sclerotium rot on Korean melon(Cucumis melo L. var. makuwa Makino) observed in Jinju, Korea in August of 2014 and 2015 is reported. The fruit rot disease on the surface of Korean melon fruit appeared as water soaked lesion followed by the development of large rotten areas with abundant white mycelial growth. Abundant white mycelial mats with globoid and white to brown sclerotia(1-3 mm) were also developed on stems near the soil line, and infected plants withered. The fungal pathogen was isolated on potato dextrose agar(PDA) and formed white colonies with numerous sclerotia on PDA. The sclerotia were globoid in shape, 1-3 mm in size, and white to brown in color. The mycelium formed typical Clamp Connection. These measurements and taxonomic characteristics were most similar to those of Sclerotium. DNA sequencing and phylogenetic analysis of the complete internal transcribed spacer rRNA gene region confirmed that the fungal isolates were Sclerotium rolfsii Saccardo. Koch’s postulates were supported by pathogenicity tests conducted on fruit. Based on mycological characteristics, pathogenicity tests, and molecular identification, the fungus was identified as Sclerotium rolfsii. To the best of our knowledge, this is the first report of a Sclerotium rot caused by S. rolfsii on Korean melon in Korea.

  • Occurrence of Sclerotium Rot in Allium tuberosum Caused by Sclerotium rolfsii in Korea
    Mycobiology, 2011
    Co-Authors: Jinhyeuk Kwon, Dong-wan Kang, Won-doo Song, Okhee Choi
    Abstract:

    This study investigated a sporadically occurring scaly stem and leaf rot disease caused by Sclerotium rolfsii in Chinese chive (Allium tuberosum Roth.) in farm fields in Onjeong-ri, Yonghyeon-myeon, Sacheon, Korea in 2010. In August, the scaly stems and leaves under the canopy of Chinese chive after planting are exposed to warm temperatures and high humidity conditions, which favor disease development of mulching cultivation in vinyl houses (Fig. 1A). We observed that the sporadically occurring disease developed mainly on scaly stems near the soil line. Infected plants gradually withered, a white mycelial mat appeared, and numerous sclerotia were produced on scaly stems surfaces near the soil line (Fig. 1B). The heavily infected scaly stems and leaves became rotted, blighted, and the whole plant eventually died. Fig. 1 Symptoms of sclerotium rot in Chinese chive (Allium tuberosum Roth.) and mycological characteristics of the pathogenic fungus Sclerotium rolfsii. A, Farmers vinyl-house culture of Chinese chive; B, Typical field symptoms on scaly stems near the soil line; ... Fifty samples of scaly stems and leaves of Chinese chive caused by Sclerotium rolfsii were cut, and after isolation, the pathogenic fungus was grown on potato dextrose agar (PDA). Detailed microscopic examination of a representative specimen was performed by scanning electron microscopy (LEO 1420VP; LEO Electron Microscopy Ltd., Cambridge, UK) and light microscopy (Axioplan 2; Carl Zeiss, Jena, Germany). The optimal growth temperature on PDA was 30℃. Aerial mycelia usually formed many narrow hyphal strands 4~8 µm wide. The white mycelium formed a typical Clamp Connection structure after 5 days of growth at optimum temperature (Fig. 1C). The sclerotia were white at first, after which they gradually turned dark brown in color, and were 1~3 mm in diameter. The maximum number of sclerotia was produced at 25~30℃. Small globoid sclerotia formed abundantly on PDA after 18 days of mycelial growth (Table 1, Fig. 1C) [1]. Table 1 Comparison of mycological characteristics of the present isolate obtained from Chinese chive (Allium tuberosum Roth.) and Sclerotium rolfsii as previously described To test pathogenicity, inoculum was prepared as previously described [2]. Briefly, the mycelial mat of the test fungus grown on PDA for 7 days was harvested and mixed thoroughly with sterilized soil. The soil mixture was used as an inoculum; 200 g of soil inoculum was placed on top of Wagner's pots, after which Chinese chive seedlings were transplanted. The inoculated pots were kept separately in a green house and observed for disease symptoms. After 12 days of inoculation, the same disease symptoms were observed, and the fungus was re-isolated from the plants inoculated artificially (Fig. 1D). To confirm the identity of the fungus, we amplified and sequenced an internal transcribed spacer (ITS) rDNA region of the isolate using the primers ITS1 and ITS4, as described by White et al. [3]. The resulting 685 bp sequence was deposited in GenBank (accession No. {"type":"entrez-nucleotide","attrs":{"text":"JF966208","term_id":"338191196"}}JF966208). Comparison with other sequences available in the GenBank database revealed that the ITS sequence shared 100% similarity with sequences of S. rolfsii (GenBank accession No. {"type":"entrez-nucleotide","attrs":{"text":"GU567776","term_id":"293628091"}}GU567776). Phylogenetic analysis was performed using MEGA4 software using the neighbor-joining method and the Tajima-Nei distance model. Previously published ITS sequences of S. rolfsii strains were included for reference, and Botryotinia fuckeliana was used as the outgroup. In the phylogenetic tree (Fig. 2), the representative isolate was placed within a clade comprising reference isolates of S. rolfsii. Fig. 2 Phylogenetic tree using internal transcribed spacer sequences showing closest known relatives of Sclerotium rolfsii, including sclerotium rot fungus infecting Allium tuberosum. DNA sequences from the NCBI nucleotide database were aligned using ClustalW, ... Based on the symptoms, mycological characteristics, ITS sequence analysis, and pathogenicity to the host plant, this fungus was identified as S. rolfsii Saccardo [1]. Sclerotium rot in Chinese chive caused by S. rolfsii has not been previously reported in Korea [4]. Cultures of S. rolfsii were deposited in the Korean Agricultural Culture Collection (KACC 45155), National Academy of Agricultural Science, Rural Development Administration, Suwon. To our knowledge, this is the first report of sclerotium rot in Chinese chive caused by Sclerotium rolfsii in Korea.

  • first report of stem rot on hosta plantaginea caused by sclerotium rolfsii in korea
    Plant Pathology Journal, 2010
    Co-Authors: Jinhyeuk Kwon
    Abstract:

    A stem rot disease caused by Sclerotium rolfsii sporadically afflicted fragrant plantain lily (Hosta plantaginea Aschers.) from 2008 to 2010 in the herb exhibition garden at Gangju Pond, which is located in Jeongchon-myon, Jinju, Korea. The fragrant plantain lilies, which are perennial plants grown in home gardens, recently were planted en mass in parks and public gardens for ornamental purposes, where they form dense communities. During summer, the stems of the plants under the canopy are exposed to warm temperatures and high humidity, which favor disease development. The disease developed mainly on stems near the soil line. Infected stems gradually died, and white mycelial mats appeared on the stem surfaces (Fig. 1A). Often, numerous sclerotia were produced on stem surfaces near the soil line. The heavily infected stems became rotted and blighted, and the whole plant eventually died. The freshly isolated pathogenic fungus grown on potato dextrose agar (PDA) was examined microscopically and culturally. The optimal growth temperature on PDA was 30°C. Aerial mycelia usually formed many narrow hyphal strands 3-9 μm wide. The white mycelium had a typical Clamp Connection structure for 4 days after growth at optimum temperature (Fig. 1D). Small globoid sclerotia formed abundantly on the PDA after 20 days of mycelial growth (Fig. 1C). The sclerotia, which were relatively uniform in size at 1-3 mm, were white at first, and then turned dark brown. The maximum number of sclerotia was produced at 25-30 oC. To test pathogenicity, inoculums were prepared with mycelial mats and mixed with autoclaved soil. Then, soil inoculums containing mycelial mats were artificially inoculated onto Hosta plantaginea. The same fungal fruiting symptoms were reproduced, and the fungus was re-isolated based on these symptoms (Fig. 1B). To identify the causal fungus, we amplified and sequenced a partial internal transcribed spacer (ITS) rDNA region of the isolate using the primers ITS1 and ITS4, as described by White et al. (1990). The resulting sequence of 684-bp was deposited in GenBank (accession no. HM355751). Phylogenetic analysis was performed using MEGA4 software, with the neighbor-joining method and Tajima–Nei distance model. Previously published ITS sequences of S. rolfsii strains were included for reference, and S. cepivorum was used as the outgroup (Harlton et al., 1995). Neighbor-joining analysis showed that the two species had similar ITS sequences (Fig. 2). In the phylogenetic tree (Fig. 2), the isolate was placed within a clade comprising reference isolates of S. rolfsii.

  • stem rot of garlic allium sativum caused by sclerotium rolfsii
    Mycobiology, 2010
    Co-Authors: Jinhyeuk Kwon
    Abstract:

    Stem rot disease was found in garlic (Allium sativum L.) cultivated from 2008 to 2010 in the vegetable gardens of some farmers in Geumsan-myon, Jinju City, Gyeongnam province in Korea. The initial symptoms of the disease were typical water-soaked spots, which progressed to rotting, wilting, blighting, and eventually death. White mycelial mats had spread over the lesions near the soil line, and sclerotia had formed over the mycelial mats on the stem. The sclerotia were globoid in shape, 1~3 mm in size, and tan to brown in color. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) medium was 30℃. The diameter of the hyphae ranged from approximately 4 to 8 µm. Typical Clamp Connection structures were observed in the hyphae of the fungus, which was grown on PDA medium for 4 days. On the basis of the mycological characteristics and pathogenicity of the fungus on the host plants, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of stem rot disease in garlic caused by S. rolfsii in Korea.