Jujube witches' broom - Candidatus Phytoplasma ziziphi 16SrV-B
Effective: May 11, 2022
Taxonomic Position: Acholeplasmatales : Acholeplasmataceae
Pest Type: Phytoplasma
Pest Code (NAPIS): FEAGMKW
This pest is a member of the following surveys: Stone Fruit
These Approved Methods are appropriate for: 2024, 2023
Pest Information
CAPS Pest Datasheet: https://download.ceris.purdue.edu/file/4382
Pest Tracker: https://pesttracker.org/pest/FEAGMKW
Hosts Identified in the CAPS Host Matrix:
Apple; Peach, Nectarine
Pest is vectored by:
Hishimonas aurifascialis, H. chinesis, and H. sellatus
None of these insect vectors are known to be present in the United States.
None of these insect vectors are known to be present in the United States.
Survey
Approved Method(s)
| Method | Detail | NAPIS Survey Method |
|---|---|---|
| Visual | Collect symptomatic plant material. | 3031 - General Visual Observation |
Survey Recommendations
The following are recommendations for executing the survey using the approved methods for pest surveillance. The recommendations are developed through literature review and consultation with subject matter experts.
Signs and Symptoms:
Symptoms include the characteristic witches’ broom appearance, in which the plant produces numerous small shoots with smaller than normal leaf size and yellowish green foliage, shortened internodes and excessive branching (Yu et al., 2012). Infection creates a typical yellow dwarf symptom in the whole plant, fruits may shrivel and prematurely drop, and the disease may commonly lead to decline and premature plant death (Wang et al., 2015).
Time of Year to Survey:
Survey during the growing season when symptoms are most likely to be visible.
Survey Site Selection:
Survey where hosts are present.
Key Diagnostic or Identification
Approved Method(s)
ID/Diagnostic:
Follow instructions for Phytoplasma Sample Screening and Confirmation on the Procedures and Techniques page.
If you have taken the hands-on phytoplasma specific training at S&T Beltsville lab, you can screen your own phytoplasma samples. Note: You will still have to follow the protocol in the linked document for confirmations.
If you have taken the hands-on phytoplasma specific training at S&T Beltsville lab, you can screen your own phytoplasma samples. Note: You will still have to follow the protocol in the linked document for confirmations.
Identification Resources:
The Identification Technology Program (ITP) has a collection of identification resources https://idtools.net/idAids/searchResults.cfm?searchString=phytoplasma&searchType=2
Mistaken Identities:
Molecular confirmation is required for identification. Symptoms may be similar to symptoms caused by other pathogens or abiotic stress.
To request a copy of diagnostic protocols, email the S&T Beltsville laboratory at APHIS-PPQCPHSTBeltsvilleSampleDiagnostics@aphis.usda.gov and use the subject line 'Diagnostic protocol request'.
References
If you are unable to find a reference, contact STCAPS@usda.gov. See the CAPS Pest Datasheet for all references.