Australian grapevine yellows - Candidatus Phytoplasma australiense 16SrXII-B
EEffective: August 18, 2010 - June 27, 2013
Resources:
Pest Tracker
CAPS Pest Datasheet
Screening Aids:
| Grapevine Yellows Disease |
Taxonomic Position:
Acholeplasmatales : Acholeplasmataceae
Pest Type:
Phytoplasma
Pest Code (NAPIS):
FGBLCXK
| No manual – See Host Matrix |
These Approved Methods are appropriate for:
Major Hosts identified in the Host Matrix:
Alfalfa; Grape; Papaya; Potato; Strawberry; Sweet gum
This list includes important economic or environmental hosts but does not represent all major hosts of the pest. Check CAPS pest datasheet for complete list of hosts.
This list includes important economic or environmental hosts but does not represent all major hosts of the pest. Check CAPS pest datasheet for complete list of hosts.
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 | Instructions | 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 |
Survey Instruction Details:
For FY 2013 surveys (Farm Bill and CAPS) please use the information in this linked document to help you collect and package your samples Davis, 2013: Grapevine yellows procedures for collecting and packaging grapevine samples
Signs:
No specific signs are present.
Symptoms:
There are a variety of symptoms, which vary according to host.
For 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.
See Grape Commodity-based Survey Reference for descriptions of symptoms by host.
For 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.
See Grape Commodity-based Survey Reference for descriptions of symptoms by host.
Key Diagnostics
ID/Diagnostic: Molecular
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).
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).
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:
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.
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.