Occurrence of Bursaphelenchus mucronatus (Nematoda: Aphelenchoididae) and the microhabitat distribution of fungi in declining pine trees in a locale in Korea. Issue 3 (13th May 2014)

• Record Type: Journal Article
• Authors: Oh, In‐Jae; Ju, Wan‐Taek; Kim, Young‐Ju; Jung, Woo‐Jin; Kim, Kil‐Yong; Park, Ro‐Dong
• Is Part Of: Entomological research. Volume 44:Issue 3(2014:May)
• Page Start: 93
• Page End: 101
• Publication Date: 2014-05-13
• Subjects: Insects -- Korea -- Periodicals; Entomology -- Periodicals; 595.709519
• DOI: 10.1111/1748-5967.12054
• Languages: English
• ISSNs: 1738-2297

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>A total of 33 pine trees with symptoms of decline were collected in Jeonnam Province, South Korea, and were examined for the presence of nematodes. About 20% of the trees sampled were positive with <italic>Bursaphelenchus</italic> species. All <italic>Bursaphelenchus</italic> species were found in recently dead or dying trees. Based on morphological observations, the nematode extracted from the declining pine trees was identified as <italic>B. mucronatus</italic>. The highly pathogenic pine wood nematode <italic>B. xylophilus</italic> was not found in any pine trees sampled. <italic>B. mucronatus</italic> was easily reared on fungus <italic>Botrytis cinerea</italic>. Twenty one fungal isolates were isolated from dead trees, fallen twigs, and healthy pine trees. The fungal isolates belonged to <italic>Trichoderma</italic> genus and were dominant in the wood of partially declining pines. The blue‐stain fungi transmitted by the <italic>Monochamus</italic> beetle were not detected. The <italic>B. mucronatus</italic> population decreased markedly on <italic>Auxarthron reticulatum</italic> DY‐2 isolated from soils. The number of nematodes also reduced on <italic>Verticillium saksenae</italic> A‐1, a nematophagous fungus, and <italic>Beauveria bassiana</italic>, an entomopathogenic fungus. This observation suggested the fungal production of nematicidal activity against <italic>B. mucronatus</italic>. When the fungal culture filtrates were also used for nematicidal activity on <italic>B. mucronatus</italic>, the culture filtrates of A‐1, DY‐2 and <italic>B. bassiana</italic> showed over 50% mortality within 48 h exposure. The fungi BC4, BC5 and BC6 isolated from declining pine trees inhibited the reproduction of <italic>B. mucronatus</italic>, and their culture filtrates also expressed nematicidal activity, indicating a possible interaction between the fungi in pine trees and nematodes at microhabitat level.</p> </abstract>