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

<p>Lilium longiflorum cv. Nellie White, commonly known as Easter lily, is an important floral crop with an annual wholesale value of over $26 million in the United States. The root-lesion nematode, <italic>Pratylenchus penetrans</italic>, is a major pest of lily due to the significant root damage it causes. In this study, we investigated the cytological aspects of this plant–nematode interaction using bright-field and transmission electron microscopy. We took advantage of an in vitro culture method to multiply lilies and follow the nematode infection over time. Phenotypic reactions of roots inoculated with P. penetrans were evaluated from 0 to 60 d after nematode infection. Symptom development progressed from initial randomly distributed discrete necrotic areas to advanced necrosis along entire roots of each inoculated plant. A major feature characterizing this susceptible host response to nematode infection was the formation of necrosis, browning, and tissue death involving both root epidermis and cortical cells. Degradation of consecutive cell walls resulted in loss of cell pressure, lack of cytoplasmic integrity, followed by cell death along the intracellular path of the nematode’s migration. <italic>Pratylenchus penetrans</italic> was never seen in the vascular cylinder as the layer of collapsed endodermal cells presumably blocked the progression of nematodes into this area of the roots. This study presents the first detailed cytological characterization of P. penetrans infection of Easter lily plants.</p>
</abstract>

Lilium longiflorum cv. Nellie White, commonly known as Easter lily, is an important floral crop with an annual wholesale value of over $26 million in the United States. The root-lesion nematode, Pratylenchus penetrans, is a major pest of lily due to the significant root damage it causes. In this study, we investigated the cytological aspects of this plant–nematode interaction using bright-field and transmission electron microscopy. We took advantage of an in vitro culture method to multiply lilies and follow the nematode infection over time. Phenotypic reactions of roots inoculated with P. penetrans were evaluated from 0 to 60 d after nematode infection. Symptom development progressed from initial randomly distributed discrete necrotic areas to advanced necrosis along entire roots of each inoculated plant. A major feature characterizing this susceptible host response to nematode infection was the formation of necrosis, browning, and tissue death involving both root epidermis and cortical cells. Degradation of consecutive cell walls resulted in loss of cell pressure, lack of cytoplasmic integrity, followed by cell death along the intracellular path of the nematode’s migration. Pratylenchus penetrans was never seen in the vascular cylinder as the layer of collapsed endodermal cells presumably blocked the progression of nematodes into this area of the roots. This study presents the first detailed cytological characterization of P. penetrans infection of Easter lily plants.

Characterization of <italic>Lilium longiflorum</italic> cv. ‘Nellie White’ Infection with Root-lesion Nematode <italic>Pratylenchus penetrans</italic> by Bright-field and Transmission Electron Microscopy

U.S. National Arboretum, U.S. Department of Agriculture

U.S. Department of Agriculture, Agricultural Research Service

Journal of Nematology

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

Characterization of  cv. ‘Nellie White’ Infection with Root-lesion Nematode  by Bright-field and Transmission Electron Microscopy

Lilium longiflorum cv. Nellie White, commonly known as Easter lily, is an important floral crop with an annual wholesale value of over $26 million in the...

Characterization of Lilium longiflorum cv. ‘Nellie White’ Infection with Root-lesion Nematode Pratylenchus penetrans by Bright-field and Transmission Electron Microscopy

Published Online: Jul 21, 2017

Page range: 2 - 11

Received: Oct 24, 2016

DOI: https://doi.org/10.21307/jofnem-2017-040

Keywords
cell biology, Easter lily, electron microscopy, root-lesion nematode

© 2017 Paulo Vieira et al., published by Sciendo

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

Characterization of Lilium longiflorum cv. ‘Nellie White’ Infection with Root-lesion Nematode Pratylenchus penetrans by Bright-field and Transmission Electron Microscopy

Published Online: Jul 21, 2017

Page range: 2 - 11

Received: Oct 24, 2016

DOI: https://doi.org/10.21307/jofnem-2017-040

Keywordscell biology, Easter lily, electron microscopy, root-lesion nematode

© 2017 Paulo Vieira et al., published by Sciendo

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

Keywords
cell biology, Easter lily, electron microscopy, root-lesion nematode