• Title/Summary/Keyword: Morphological Characters

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Morphological Characters and Seed Transmission of Bipolaris panici-miliacei Causing Leaf Spot of Common Millet (기장 점무늬병균 (Bipolaris panici-miliacei)의 형태적 특징과 종자전염)

  • 이두형
    • Korean Journal Plant Pathology
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    • v.13 no.1
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    • pp.18-21
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    • 1997
  • Bipolaris panici-miliacei, Cercospora fusimaculans, Fusarium moniliforme and Rhizoctonia solani were pathogenic fungi detected from 5 seed samples of common millet (Panicum miliaceum). Morphological characters of B. panici-miliacei were as follows. Conidiophores were dark olivaceous brown, simple, cylindrical, geniculate, and septate. Conidia were fusoid, dark olivaceous brown, tapering gradually toward the ends, straight to slightly curved, 3~13 distoseptate, and 29.4~155.4$\times$10~26 ${\mu}{\textrm}{m}$ in size with dark hilum included within the contour of the basal cell. Seed infection with B. panici-miliacei caused seed rotting, coleoptile spot, and seedling blight of common millet plants. According to the inoculation experiments, B. panici-miliacei showed strong virulence on the young seedlings of common millet, but very weak virulence on the young seedlings of rice (Oryza sativa) and foxtail millet (Setaria italica).

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Description of Fungus Gnat, Lycoriella mali Fitch (Diptera: Sciaridae) from Korea (버섯해충 Lycoriella Mali (긴수염버섯파리: 신칭)에 관한 보고)

  • Heung-Su Lee;Kyu-Chin Kim;Chung-Gyoo Park;Won-Kyo Shin
    • Korean journal of applied entomology
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    • v.38 no.3
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    • pp.209-212
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    • 1999
  • A species of fungus gnat collected from mushroom house was identified as Lycoriella mali Fitch. Morphological characters of this species ar described and briefly compared with other associated species infesting mushrooms.

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Cyanobacterial Taxonomy: Current Problems and Prospects for the Integration of Traditional and Molecular Approaches

  • Komarek, Jiri
    • ALGAE
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    • v.21 no.4
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    • pp.349-375
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    • 2006
  • The application of modern ecological, ultrastructural and molecular methods, aided by the cultivation of numerous cyanobacterial morphotypes, has substantially changed our knowledge of these organisms. It has led to major advances in cyanobacterial taxonomy and criteria for their phylogenetic classification. Molecular data provide basic criteria for cyanobacterial taxonomy; however, a correct phylogenetic system cannot be constructed without combining genetic data with knowledge from the previous 150 years research of cyanobacterial diversity. Thus, studies of morphological variation in nature, and modern morphological, ultrastructural, ecophysiological and biochemical characters need to be combined in a “polyphasic” approach. Taxonomic concepts for generic and infrageneric ranks are re-evaluated in light of combined phenotypic and molecular criteria. Despite their usefulness in experimental studies, the limitations of using strains from culture collections for systematic and nomenclatural purposes is highlighted. The need for a continual revision of strain identification and proper nomenclatural practice associated with either the bacteriological or botanical codes is emphasized. Recent advances in taxonomy are highlighted in the context of prospects for understanding cyanobacterial diversity from natural habitats, and the evolutionary and adaptational processes that cyanobacteria undergo.

Occurrence of Japanese Gall-forming Thrips, Ponticulothrips diospyrosi Haga et Okajima(Thysanoptera:Phlaelthripidae) in Korea (감관총채벌레(신칭:Ponticulothrips diospyrosi Haga et Okajima)(Thysanoptera:Phlaelthripidae)의 발생)

  • Lee, Kyu-Chul;Park, Chung-Gyoo;Choo, Ho-Yul;Choo, Ho-Yul;Woo, Kun-Suk;Kang, Chang-Heon
    • Korean journal of applied entomology
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    • v.41 no.1
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    • pp.1-4
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    • 2002
  • A thysanopteran pest pest was collected from the damaged leaves of Fuyu persimmon (Diospyrosi kaki) at Changwon, Gyeongnam province in June, 2000. The thrips was identified as Japanese gall-forming thrips, Ponticulothrips diospyrosi(Phlaeothripidae). which is newly recorded in Korea. Brief morphological and ecological characters, damage symptoms, and distribution in Gyeongnam province were provided.

Studies on the Putative Parent of Cultivated Chrysanthemum (IV) (재배국의 추정원종에 관한 연구(IV))

  • 한창열
    • Journal of Plant Biology
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    • v.11 no.1
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    • pp.33-37
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    • 1968
  • Present investigation was carried out in order to make clear the fertility, morphological characters, and chromosome numbers of interspecific hybrids of Chrysanthemum Zauadskii, C. indicum, and C. lavandulaefolium. 1. Hybrids were not self-pollinated. When sib-crossed the fertility was 1.3~19.3%. 2. F2 individuals were variable in their morphological Characters. 3. Chromosome numbers of three putative parents were different from those reported previously: C. zawadskii 2n=36, C. indicum 2n=20, C. lavandulaefolium 2n=16, $C. indicum{\times}C. zawadskii 2n=28, C. zawadskii{\times}C. indicum-1 2n=28, C. zawadskii{\times}C. indicum-2 2n=28, C. zawadskii{\times}C. indicum-3 2n=28, C. zawadskii{\times}C. indicum-4 2n=28, C. zawadskii{\times}C. indicum-5 2n=28, C. zawadskii {\times}C. lavandulaefolium-1 2n=26, C. zawadskii{\times}C. lavandulaefolium-2 2n=26.$

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A report on species of phyllidiid and polycerid nudibranch including two species new to Korea

  • Jung, Daewui;Lee, Jongrak;Kim, Chang-Bae
    • Journal of Species Research
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    • v.2 no.1
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    • pp.7-14
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    • 2013
  • During a systematic study on Korean nudibranchs, two phyllidiid and two polycerid species were collected and identified with examination of their external morphological characters. As a result of the study, two phyllidiid species, Phyllidia ocellata Cuvier, 1804 and Phyllidiella pustulosa (Cuvier, 1804) were redescribed since there was no descriptions of these species with Korean specimens. And two polycerid species, Thecacera pennigera (Montagu, 1815) and Triopha catalinae (Cooper, 1863) were described as new to Korean fauna. Diagnostic characters of these species are described with illustrations in this study. DNA barcode data from three species examined were also provided for a supplement to morphological identifications.

Pythium subutonaiense, A New Aquatic Oomycete from Southern China Based on Morphological and Molecular Characters

  • Chen, Jia-Jia;Zheng, Xiao-Bo
    • Mycobiology
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    • v.47 no.3
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    • pp.273-279
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    • 2019
  • A new species, Pythium subutonaiense, isolated from aquatic environments (lake) in China is being described based on morphological characters and molecular evidence. The isolates grew at temperatures between $5^{\circ}C$ and $38^{\circ}C$, and the optimum temperature was $30^{\circ}C$, with a radial growth rate of 17.6 mm at $25^{\circ}C$ per day. It is homothallic and characterized by globose to sub-globose shaped and mostly terminal or sometimes catenulate hyphal swellings, filamentous non-inflated sporangia, and smooth oogonia with hypogynous and monoclinous antheridia that contained one plerotic oospore. In phylogenetic analysis, inferred based on the internal transcribed spacer region of the ribosomal RNA gene and mitochondrial cytochrome c oxidase subunit 1 gene, the new species formed a distinct lineage in Pythium clade B. Differences between the new species and phylogenetically related and morphologically similar species are discussed.

First Record of Eucephalobus iaculocaudatus(Nematoda, Rhabditida, Cephalobidae) from South Korea

  • Kim, Taeho
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.4
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    • pp.345-348
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    • 2021
  • The genus Eucephalobus Steiner, 1936, belonging to the family Cephalobidae Filipjev, 1934 (Cephalobomorpha), represents a group of bacterial feeding nematodes. Although this group is cosmopolitan and species-rich, only two species have been reported from South Korea. Eucephalobus iaculocaudatus Bostrom and Holovachov, 2011 was collected from natural forest in Chungcheongbuk-do, South Korea. This species shows typical morphological characters of the genus Eucephalobus, including a bicornuate labial probolae, cephalic probolae absent and three lateral incisures. However, E. iaculocaudatus is distinguished from other Eucephalobus species by conoid tail with a harpoon-shape mucro in female and ragged mucro in male. In this study, detailed morphological characters and morphometrics of E. iaculocaudatus are described and illustrated based on optical microscopy.

Enhanced technique for Arabic handwriting recognition using deep belief network and a morphological algorithm for solving ligature segmentation

  • Essa, Nada;El-Daydamony, Eman;Mohamed, Ahmed Atwan
    • ETRI Journal
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    • v.40 no.6
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    • pp.774-787
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    • 2018
  • Arabic handwriting segmentation and recognition is an area of research that has not yet been fully understood. Dealing with Arabic ligature segmentation, where the Arabic characters are connected and unconstrained naturally, is one of the fundamental problems when dealing with the Arabic script. Arabic character-recognition techniques consider ligatures as new classes in addition to the classes of the Arabic characters. This paper introduces an enhanced technique for Arabic handwriting recognition using the deep belief network (DBN) and a new morphological algorithm for ligature segmentation. There are two main stages for the implementation of this technique. The first stage involves an enhanced technique of the Sari segmentation algorithm, where a new ligature segmentation algorithm is developed. The second stage involves the Arabic character recognition using DBNs and support vector machines (SVMs). The two stages are tested on the IFN/ENIT and HACDB databases, and the results obtained proved the effectiveness of the proposed algorithm compared with other existing systems.

First report of Mesorhabditis microbursaris(Nematoda: Rhabditida: Mesorhabditidae) from Korea

  • Jiyeon, Kim;Taeho, Kim
    • Journal of Species Research
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    • v.11 no.4
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    • pp.330-334
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    • 2022
  • Mesorhabditis microbursaris (Steiner, 1926) Sudhaus, 2011, belonging to the family Mesorhabditidae (Rhabditomorpha), is newly reported from South Korea. During a survey of small streams, M. microbursaris was isolated from sedimentary soil samples. The genus Mesorhabditis Osche, 1952 nematodes are distributed all over the world and are mostly found from terrestrial habitats, however are sometimes found in freshwater. At present, 34 valid species have been recorded from Mesorhabditis; however, only three species have been reported from South Korea. Mesorhabditis microbursaris exhibits morphological characters of other congeneric species, including shorter distance between vulva and anus than the distance between anus and tail, rudimentary bursa with narrow velum and short genital papillae, shorter spicules than tail and conical tail. However, this species can be distinguished from other Mesorhabditis species by its morphometric characters and three pairs of bursal papillae. Details of the morphological characteristics and morphometrics of M. microbursaris are described and illustrated based on optical microscopy.