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

<p>Browning rhizome (also known as “browning tuber disease”) in Indian lotus (<italic>Nelumbo nucifera</italic>) caused by the nematode <italic>Hirschmanniella diversa</italic> is an emerging agronomic problem. In this study, the authors documented the early infection processes of <italic>H. diversa</italic> in the apices of young rhizomes of Indian lotus by electron microscopy analysis using an artificial inoculation method. Nematodes were attracted to young rhizome apices, invading them via narrow indentations by 4.5 hr after inoculation. Host cells adjacent to the cavity around the invading nematodes were absent and appeared to have disintegrated during infestation. Following contact with the nematodes, host cell walls and cellular contents became electron-dense and less defined, likely due to digestive enzymes secreted by the invading nematodes. Nematodes invaded to a depth of about 1 mm by 24 hr after inoculation, but did not penetrate the plant any further vertically, similar to the observation of browning in mature rhizomes in the field. The authors propose that the invasion sites of young rhizome apices become blackish-brown blotches as rhizomes mature in the field due to oxidation.</p>
</abstract>

Browning rhizome (also known as “browning tuber disease”) in Indian lotus (Nelumbo nucifera) caused by the nematode Hirschmanniella diversa is an emerging agronomic problem. In this study, the authors documented the early infection processes of H. diversa in the apices of young rhizomes of Indian lotus by electron microscopy analysis using an artificial inoculation method. Nematodes were attracted to young rhizome apices, invading them via narrow indentations by 4.5 hr after inoculation. Host cells adjacent to the cavity around the invading nematodes were absent and appeared to have disintegrated during infestation. Following contact with the nematodes, host cell walls and cellular contents became electron-dense and less defined, likely due to digestive enzymes secreted by the invading nematodes. Nematodes invaded to a depth of about 1 mm by 24 hr after inoculation, but did not penetrate the plant any further vertically, similar to the observation of browning in mature rhizomes in the field. The authors propose that the invasion sites of young rhizome apices become blackish-brown blotches as rhizomes mature in the field due to oxidation.

Ultrastructure of <italic>Hirschmanniella diversa</italic> early-stage infection in browning rhizomes of Indian lotus

Journal of Nematology

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

Ultrastructure of  early-stage infection in browning rhizomes of Indian lotus

running-head

Browning rhizome (also known as “browning tuber disease”) in Indian lotus (Nelumbo nucifera) caused by the nematode Hirschmanniella diversa is an emerging...

Ultrastructure of Hirschmanniella diversa early-stage infection in browning rhizomes of Indian lotus

Published Online: Jul 06, 2020

Page range: 1 - 9

Received: Jun 10, 2019

DOI: https://doi.org/10.21307/jofnem-2020-055

Keywords
Digestive enzyme, Tuber browning

© 2020 Shigeru Uematsu et al., published by Sciendo.

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

Ultrastructure of Hirschmanniella diversa early-stage infection in browning rhizomes of Indian lotus

Published Online: Jul 06, 2020

Page range: 1 - 9

Received: Jun 10, 2019

DOI: https://doi.org/10.21307/jofnem-2020-055

KeywordsDigestive enzyme, Tuber browning

© 2020 Shigeru Uematsu et al., published by Sciendo.

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

Keywords
Digestive enzyme, Tuber browning