UC IPM Online UC ANR home page UC IPM home page

UC IPM Home

SKIP navigation

 

How to Manage Pests

UC Pest Management Guidelines


Root lesion nematode adults and eggs.

Fig

Nematodes

Scientific Names:
Lesion nematode: Pratylenchus vulnus
Root knot nematode: Meloidogyne incognita and M. javanica
Dagger nematode: Xiphinema index

(Reviewed 7/06, updated 7/06)

In this Guideline:


DESCRIPTION OF THE PESTS

Nematodes are microscopic roundworms that live in diverse habitats. Plant parasitic nematodes live in soil and plant tissues and feed on plants by puncturing and sucking the cell contents with a spearlike mouthpart called a stylet.

DAMAGE

Little information is available on damage to figs resulting from a nematode infestation. Lesion, root knot, and dagger nematodes are known to cause reduction in growth and yield. The trees are likely to be more susceptible to temperature and water stress.

SYMPTOMS

The symptoms described below are indicative of a nematode problem, but are not diagnostic as they could result from other causes as well. Lesion nematode infested trees may appear stunted with very few feeder roots. The roots may have reddish brown lesions that eventually turn dark. Root knot nematode infested trees are also likely to have reduced growth and appear stunted. The roots have distinctive swellings, called galls. Dagger nematode causes gall formation on root tips.

FIELD EVALUATION

If the symptoms described above are present and no cause is evident, sample the orchard to determine if lesion, root knot, dagger, or other plant parasitic nematodes are present.

If nematode species have not previously been identified, take soil samples and send then to a diagnostic laboratory for identification. Divide the field into sampling blocks of not more than five acres each that are representative of cropping history, crop injury, or soil texture. Within each block, take several subsamples randomly from the frequently wetted zones at the edge of the tree canopy. Take samples from within the root zone (6 to 36 inch depth) and include some feeder roots when possible. Mix the subsamples thoroughly and make a composite sample of about 1 quart (1 liter) for each block. Place the samples in separate plastic bags, seal them and place a label on the outside with your name, address, location, and the current/previous crop and the crop you intend to grow. Keep samples cool (do not freeze), and transport as soon as possible to a diagnostic laboratory. Contact your farm advisor for more details about sampling, to help you find a laboratory for extracting and identifying nematodes, and for help in interpreting sample results.

MANAGEMENT

Nematode problems on fig in California have not been extensively studied, so no specific treatment recommendations are made. However, trees planted in fumigated soil are known to grow considerably better than trees planted in nonfumigated soil. Metam sodium* (Vapam, Soil Prep) and 1,3-dichloropropene* (Telone 11) are available for preplant use on figs. Fumigants such as metam sodium* (Vapam, Soil Prep) and 1,3-dichloropropene* (Telone 11) are a prime source of volatile organic compounds (VOCs), which are a major air quality issue. Fumigate only as a last resort when other management strategies have not been successful or are not available.

* Permit required from county agricultural commissioner for purchase or use.

[Precautions]

PUBLICATION

[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Fig
UC ANR Publication 3447
Nematodes
B. B. Westerdahl, Nematology, UC Davis
Acknowledgment for contributions to Nematodes:
U. C. Kodira, Plant Pathology, UC Davis

Top of page


Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2014 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   /PMG/r261200111.html revised: April 25, 2014. Contact webmaster.