Root-Knot Nematodes: Trouble Underground

— Written By Thomas Glasgow
en Español / em Português

El inglés es el idioma de control de esta página. En la medida en que haya algún conflicto entre la traducción al inglés y la traducción, el inglés prevalece.

Al hacer clic en el enlace de traducción se activa un servicio de traducción gratuito para convertir la página al español. Al igual que con cualquier traducción por Internet, la conversión no es sensible al contexto y puede que no traduzca el texto en su significado original. NC State Extension no garantiza la exactitud del texto traducido. Por favor, tenga en cuenta que algunas aplicaciones y/o servicios pueden no funcionar como se espera cuando se traducen.


Inglês é o idioma de controle desta página. Na medida que haja algum conflito entre o texto original em Inglês e a tradução, o Inglês prevalece.

Ao clicar no link de tradução, um serviço gratuito de tradução será ativado para converter a página para o Português. Como em qualquer tradução pela internet, a conversão não é sensivel ao contexto e pode não ocorrer a tradução para o significado orginal. O serviço de Extensão da Carolina do Norte (NC State Extension) não garante a exatidão do texto traduzido. Por favor, observe que algumas funções ou serviços podem não funcionar como esperado após a tradução.


English is the controlling language of this page. To the extent there is any conflict between the English text and the translation, English controls.

Clicking on the translation link activates a free translation service to convert the page to Spanish. As with any Internet translation, the conversion is not context-sensitive and may not translate the text to its original meaning. NC State Extension does not guarantee the accuracy of the translated text. Please note that some applications and/or services may not function as expected when translated.

Collapse ▲
Root-knot nematodes have a tremendous host range and may be involved in more landscape and garden problems than you realize. Recently I submitted salvia from my home landscape to our Plant Disease and Insect Clinic on campus, fairly confident in my diagnosis of Tomato Spotted Wilt Virus (TSWV). Not for the first time, the Clinic shot down my diagnosis and informed me that root-knot
nematode was the primary problem. I didn’t look closely enough.
Shortly afterward, our crops agent Mike Carroll and I inspected the rootball of a boxwood someone had dropped off at the office, and the roots were obviously heavily infested with root-knot nematodes.
A third example this fall involves watermelon plants grown in a local community garden that our office works with. As seen in the images below, root-knot nematode damage to watermelon roots is quite dramatic.
So what can be done in non-commercial settings such as home landscapes and community vegetable gardens? Start with the Management of root-knot nematodes in bedding plants, which provides non-chemical strategies such as plant selection, site preparation, and bio-control with marigolds. This information note cautions homeowners against purchasing marketed chemical products for  nematodes, stating  “There are no effective nematicides (pesticides that affect nematodes) available for homeowners … “. For the vegetable garden, see Control of root-knot nematodes in the home vegetable garden. Once again, variety selection, bio-control and various cultural practices will take center stage. You won’t eliminate nematodes from the site, but you can make them less relevant.
infested Japanese boxwood roots

Buxus microphylla (Japanese boxwood) is highly susceptible to root-knot nematodes. Arrows point to the galls typically found on infested roots.

watermelon root

Severe Damage to Watermelon Roots

several watermelon roots

Longer sections of infested watermelon roots.