How to Manage Pests
UC Pest Management Guidelines
Pin nematode: Paratylenchus hamatus
Nematodes are microscopic, unsegmented, roundworms that live in diverse habitats. Plant parasitic nematodes feed on plant roots by piercing and sucking the cell contents with a spearlike mouthpart called a stylet. They usually live in soil and plant tissues.
The nematodes listed above have been found in pistachio orchards in California but have not been associated with damage to this crop.
Tree symptoms may suggest but are never sufficient to diagnose a nematode problem. To adequately diagnose a nematode problem, soil and root samples must be examined by a diagnostic laboratory to determine if nematodes are present.
Although nematodes have not previously been found to cause problems on pistachios in California, if the cause for a problem cannot be found, soil samples could be taken to determine if nematodes are present in high numbers. 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.
No management practices are recommended because nematodes are not currently recognized as causing problems on pistachios in California. Pistachia vera rootstock is known to be susceptible to root knot nematode, whereas P. atlantica, P. terrebinthus and P. integerrima currently appear to be resistant or poor hosts for root knot and lesion nematodes.
UC IPM Pest Management Guidelines:
UC ANR Publication 3461
B. B. Westerdahl, Nematology, UC Davis
Acknowledgment for contributions to Nematodes:
U. C. Kodira, Plant Pathology, UC Davis