How to Manage Pests

UC Pest Management Guidelines



Scientific names:
Root knot nematodes: Meloidogyne incognita and Meloidogyne spp.

(Reviewed 12/15, updated 12/15)

In this Guideline:


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 removing cell contents with a spearlike mouthpart, called a stylet.

Nematode problems in pecan have not been reported in California. The following genera of plant parasitic nematodes have been detected in pecan orchard soils in other states: Meloidogyne, Mesocriconema (formerly Criconemella), Trichodorus, Paratrichodorus, Helicotylenchus, Pratylenchus, Tylenchorhynchus, Hoplolaimus, Gracilacus, Longidorus, and Xiphinema. Of these only Meloidogyne incognita is considered likely to be pathogenic.

In other states root knot nematode causes galling on some rootstocks; galls vary in size from 0.0625 to 0.25 inch. Aboveground symptoms include chlorotic foliage, stunted trees with sparse foliage, and some trees may be barren. If you suspect nematodes are causing a problem in pecans, contact your farm advisor.


[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Pecan
UC ANR Publication 3456


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 © 2017 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   Contact webmaster.