Australian grapevine yellows - Candidatus Phytoplasma australiense 16SrXII-B
Effective: April 6, 2018
Taxonomic Position: Acholeplasmatales : Acholeplasmataceae
Pest Type: Phytoplasma
Pest Code (NAPIS): FGBLCXK
This pest is a member of the following surveys: Grape, Solanaceous Hosts
These Approved Methods are appropriate for: 2024, 2023, 2022, 2021, 2020, 2019, 2018, 2017, 2016, 2015
Pest Information
CAPS Pest Datasheet: https://download.ceris.purdue.edu/file/2993
Pest Tracker: https://pesttracker.org/pest/FGBLCXK
Hosts Identified in the CAPS Host Matrix:
Alfalfa; Grape; Papaya; Potato; Strawberry; Sweet gum
Pest is vectored by:
The cixiic planthopper, Zeoliarus (Oliarus) atkinsoni and Zeoliarus oppositus, which occur in New Zealand, are the only known vectors of Ca. P. australiense. Z. atkinsoni has only been demonstrated to transmit the phytoplamsa from Phormium to Phormium (Phormium yellows); while Z. oppositus is polyphagous and has been reported on many different plants. To date, the insect vector responsible for the spread of Ca. P. australiense in Australia is not known.
Survey
Approved Method(s)
| Method | Detail | NAPIS Survey Method |
|---|---|---|
| Visual | Collect symptomatic leaf material. Be sure that each plant that is sampled exhibits shriveling of the fruiting cluster. | 3031 - General Visual Observation |
Method Notes:
Follow instructions in Phytoplasma Sample Screening and Confirmation
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.
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:
No specific signs are present.
Symptoms:
There are a variety of symptoms, which vary according to host.
Grape: Symptoms of the grapevine yellows disease can be observed in leaves, tendrils, and fruiting clusters. Leaves of white grape varieties tend to become yellowed and may have veinal necrosis, as well as downward curling of the leaf margins. Unlike some other grapevine diseases, the grapevine yellows diseases are characterized by shriveling/abortion/necrosis of fruiting clusters.
Solanaceous Hosts: In potato, upward rolling and purpling of the leaves were observed. The symptoms appeared similar to those of "zebra chip", a disorder of potato recently found to be associated with "Candidatus Liberibacter solanacearum" in New Zealand and the United States. In Jerusalem cherry (Solanum pseudocapsicum), symptoms include: witches" broom, foliar yellowing, and reduced leaf size.
See Grape or Solanaceous Commodity-based Survey Reference or the S&T Pest Datasheet for descriptions of symptoms by host.
Grape: Symptoms of the grapevine yellows disease can be observed in leaves, tendrils, and fruiting clusters. Leaves of white grape varieties tend to become yellowed and may have veinal necrosis, as well as downward curling of the leaf margins. Unlike some other grapevine diseases, the grapevine yellows diseases are characterized by shriveling/abortion/necrosis of fruiting clusters.
Solanaceous Hosts: In potato, upward rolling and purpling of the leaves were observed. The symptoms appeared similar to those of "zebra chip", a disorder of potato recently found to be associated with "Candidatus Liberibacter solanacearum" in New Zealand and the United States. In Jerusalem cherry (Solanum pseudocapsicum), symptoms include: witches" broom, foliar yellowing, and reduced leaf size.
See Grape or Solanaceous Commodity-based Survey Reference or the S&T Pest Datasheet for descriptions of symptoms by host.
Key Diagnostic or Identification
Approved Method(s)
ID/Diagnostic:
Follow instructions in Phytoplasma Sample Screening and Confirmation
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.
Mistaken Identities:
In grape, symptoms may resemble mechanical disruption to the phloem, flavescence doree, bois noir, Goldgelbe Vergilbung, leaf curl, berry shrivel, and two other phytoplasmas found in grape: tomato big bud (TBB) and a second, uncharacterized phytoplasma found in Australian grapes.
In Progress / Literature-based Diagnostics:
Molecular: A "universal" PCR assay has been developed that enables amplification of the 16S rRNA genes of phytoplasmas.
Digestion of these PCR products with selected restriction enzymes provides a DNA fingerprint in the form of 16S rDNA fragment patterns that can be used to determine phytoplasma identity (Ahrens and Seemuller, 1992; Deng and Hiruki, 1991; Lee et al., 1993; Smart et al., 1996; Gibb et al., 1999).
PCR assays have been developed to detect only the Australian Grapevine Yellows phytoplasma in grape (Davis et al., 1997; Gibb et al., 1999).
Green et al. (1999) developed an "easy and efficient" DNA extraction method from woody plants for detection of phytoplasmas by PCR.
Digestion of these PCR products with selected restriction enzymes provides a DNA fingerprint in the form of 16S rDNA fragment patterns that can be used to determine phytoplasma identity (Ahrens and Seemuller, 1992; Deng and Hiruki, 1991; Lee et al., 1993; Smart et al., 1996; Gibb et al., 1999).
PCR assays have been developed to detect only the Australian Grapevine Yellows phytoplasma in grape (Davis et al., 1997; Gibb et al., 1999).
Green et al. (1999) developed an "easy and efficient" DNA extraction method from woody plants for detection of phytoplasmas by PCR.
References
- Ahrens, U., and Seemuller, E. 1992. Detection of DNA of plant pathogenic mycoplasma-like organisms by a polymerase chain reaction that amplifies a sequence of the 16S rRNA gene. Phytopathology 82(8): 828-832.
- Davis, R.E., Dally, E.L., Gundersen, D.E., Lee, I.M., and Habili, N. 1997. Candidatus Phytoplasma australiense, a new phytoplasma taxon associated with Australian grapevine yellows. International Journal of Systematic Bacteriology 47(2): 262-269.
- Deng, S., and Hiruki, C. 1991. Amplification of 16S rRNA from culturable and non-culturable mollicutes. Journal of Microbiological Methods 14: 53-61.
- Gibb, K.S., Constable, F.E., Moran, J.R., and Padovan, A.C. 1999. Phytoplasmas in Australian grapevines - detection, differentiation and associated diseases. Vitis 38(3): 107-114.
- Green, M.J., Thompson, D.A., and MacKenzie, D.J. 1999. Easy and efficient DNA extraction from woody plants for detection of phytoplasmas by polymerase chain reaction. Plant Disease 83: 482-485.
- Lee, I.M., Hammond, R.W., Davis, R.E., and Gundersen, D.E. 1993. Universal amplification and analysis of pathogen 16S rDNA for classification and identification of mycoplasmalike organisms. Phytopathology 83(8): 834-842.
- Smart, C.D., Schneider, B., Blomquist, C.L., Guerra, L.J., Harrison, N.A., Ahrens, U., Lorenz, K.H., Seemuller, E., and Kirkpatrick, B.C. 1996. Phytoplasma-specific PCR primers based on sequences of the 16S-23S rRNA spacer region. Applied and Environmental Microbiology 62(8): 2988-2993.
If you are unable to find a reference, contact STCAPS@usda.gov. See the CAPS Pest Datasheet for all references.