Studies on marine fungal-nematode associations and plant degradation

  • Samuel P. Meyers
  • Bruce E. Hopper
Experimental Ecology — Its Significance As A Marine Biological Tool

Summary

1. Studies of the broad-leafed turtle grass,Thalassia testudinumKönig, have revealed a diverse range of fungal infestation different in generic composition and dynamics of attack from that found on submerged wood. Certain of the fungi, notably the AscomyceteLindra thalassiae, initiate considerable degradation of leaf tissue and show a developmental cycle in nature related to the physiological state of the host plant.

2. Use of fungal-cellulose mats as a “trapping” substrate has been extremely effective for discernment of ecologically significant shifts in nematode concentrations, especially those of the omnivorous species,Metoncholaimus scissus.

3. Patterns of activity ofM. scissus, as well as those of various foliicolous nematodes, suggest that loci of organic material, such as fungal infested leaves and decaying plant tissue, significantly affect biological activity of these animals.

4. Laboratory analysis of degraded cotton cellulose filters show a striking incidence of fungal reproduction of the ascomycetous fungusLulworthia, along with development of a considerable associated nematode fauna, especially species ofViscosia (V. macramphida) andLeptolaimus (L. plectoides). Successional patterns in nematode development are noted with continued degradation of the cotton cellulose matrix.

Studien über marine Pilz-Nematoden-Assoziationen und Pflanzendegradation

Kurzfassung

Untersuchungen am SeegrasThalassia testudinumKönig haben ergeben, daß sich hier Pilzinfektionen hinsichtlich der Komposition der beteiligten Gattungen und der Dynamik des Befalls von den am untergetauchten Holz festgestellten Infektionen unterscheiden. Bestimmte Pilze, insbesondere der AscomycetLindra thalassiae, leiten eine erhebliche Degradation des Blattgewebes ein und zeigen einen Entwicklungszyklus, welcher in Beziehung steht zum physiologischen Zustand der Wirtspflanze. Die Anwendung von Pilz-Zellulose-Matten als „Einfangsubstrat“ war außerordentlich erfolgreich für das Erkennen ökologisch signifikanter Verschiebungen in den Nematodenkonzentrationen, insbesondere bei der omnivoren ArtMetoncholaimus scissus. Die Aktivitätsmuster vonM. scissus — ebenso wie die verschiedener foliicolöser Nematoden — deuten darauf hin, daß pilzinfizierte und zerfallende Pflanzenteile in entscheidendem Maße die biologische Aktivität dieser Tiere beeinflussen. Laboratoriumsanalysen degradierter Wollzellulosefilter lassen eine überraschend starke Vermehrung des AscomycetenLulworthia erkennen und gleichzeitig die Entwicklung einer beachtlichen Fauna assoziierter Nematodenarten, insbesondere vonViscosia macramphida undLeptolaimus plectoides. Im Verlaufe der weiteren Degradation der Wollzellulosematrix kommt es bei der Nematodenfauna zu entsprechenden Sukzessionen.

Literature cited

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Copyright information

© Biologischen Anstalt Helgoland 1967

Authors and Affiliations

  • Samuel P. Meyers
    • 1
    • 2
  • Bruce E. Hopper
    • 1
    • 2
  1. 1.Institute of Marine ScienceUniversity of MiamiMiamiUSA
  2. 2.Entomology Research InstituteCanada Department of AgricultureOttawaCanada

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