<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Transmission electron microscopy (TEM) was used to compare the ultrastructural differences between healthy male florets (anthers) and one floret parasitized by <italic>Ficophagus laevigatus</italic> in late phase C syconia of <italic>Ficus laevigata</italic> from southern Florida. Previous light-microscopic examination of paraffin-sectioned material showed that <italic>F. laevigatus</italic>-infested anthers of <italic>F. laevigata</italic> manifested as malformed, often with aberrant pollen and hypertrophied epidermal cells closest to regions containing propagating nematodes. Female florets or fig wasp-parasitized female florets were not observed to be parasitized by nematodes. Considering that plant-feeding in the Aphelenchoididae is purportedly much less specialized than in certain groups of the Tylenchomorpha, where specialized hypertrophied feeder cells are produced in response to nematode feeding, we examined the putative induced response in this unusual aphelenchoidid system with the higher resolution afforded by TEM. TEM confirmed the expression of significant epidermal cell hypertrophy of the anther and anther filament in the presence of propagating nematodes, which was expressed as cell enlargement (2-5X), fractionation of large electron-dense stores into smaller aggregates, irregularly shaped nuclei enclosed by an elongated nuclear envelope, nucleolus enlargement, increased organelle production, and apparent metabolism with increased numbers of mitochondria, pro-plastids, and endoplasmic reticulum, as well as increased thickening of the cell walls. Pathological effects were observed in adjacent cells/tissue (e.g., anther and anther filament parenchymal cells, pollen tubes, pollen, and endothecium) with apparent diminishment as the distance from propagating nematodes increased (which was also probably affected by number of nematodes). Some TEM sections captured previously undocumented ultrastructural highlights of propagating individuals of <italic>F. laevigatus</italic>.</p>
</abstract>

Transmission electron microscopy (TEM) was used to compare the ultrastructural differences between healthy male florets (anthers) and one floret parasitized by Ficophagus laevigatus in late phase C syconia of Ficus laevigata from southern Florida. Previous light-microscopic examination of paraffin-sectioned material showed that F. laevigatus-infested anthers of F. laevigata manifested as malformed, often with aberrant pollen and hypertrophied epidermal cells closest to regions containing propagating nematodes. Female florets or fig wasp-parasitized female florets were not observed to be parasitized by nematodes. Considering that plant-feeding in the Aphelenchoididae is purportedly much less specialized than in certain groups of the Tylenchomorpha, where specialized hypertrophied feeder cells are produced in response to nematode feeding, we examined the putative induced response in this unusual aphelenchoidid system with the higher resolution afforded by TEM. TEM confirmed the expression of significant epidermal cell hypertrophy of the anther and anther filament in the presence of propagating nematodes, which was expressed as cell enlargement (2-5X), fractionation of large electron-dense stores into smaller aggregates, irregularly shaped nuclei enclosed by an elongated nuclear envelope, nucleolus enlargement, increased organelle production, and apparent metabolism with increased numbers of mitochondria, pro-plastids, and endoplasmic reticulum, as well as increased thickening of the cell walls. Pathological effects were observed in adjacent cells/tissue (e.g., anther and anther filament parenchymal cells, pollen tubes, pollen, and endothecium) with apparent diminishment as the distance from propagating nematodes increased (which was also probably affected by number of nematodes). Some TEM sections captured previously undocumented ultrastructural highlights of propagating individuals of F. laevigatus.

Ultrastructural study of anther parasitism of <italic>Ficus laevigata</italic> by <italic>Ficophagus laevigatus</italic> (Aphelenchoididae)

Journal of Nematology

This work is licensed under the Creative Commons Attribution 4.0 International License.

Ultrastructural study of anther parasitism of  by  (Aphelenchoididae)

Transmission electron microscopy (TEM) was used to compare the ultrastructural differences between healthy male florets (anthers) and one floret parasitized by...

Ultrastructural study of anther parasitism of Ficus laevigata by Ficophagus laevigatus (Aphelenchoididae)

Article Category: Research paper

Publié en ligne: 18 mai 2023

Pages: -

Reçu: 09 janv. 2023

DOI: https://doi.org/10.2478/jofnem-2023-0010

Mots clés
fig, fig nematode, morphology, plant parasitism

© 2023 Robin M. Giblin-Davis et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Ultrastructural study of anther parasitism of Ficus laevigata by Ficophagus laevigatus (Aphelenchoididae)

Article Category: Research paper

Publié en ligne: 18 mai 2023

Pages: -

Reçu: 09 janv. 2023

DOI: https://doi.org/10.2478/jofnem-2023-0010

Mots clésfig, fig nematode, morphology, plant parasitism

© 2023 Robin M. Giblin-Davis et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Mots clés
fig, fig nematode, morphology, plant parasitism