April 5, 2005
Source: British Society for Plant Pathology, New Disease Reports, Vol. 11 [edited]

First report of Potato Wart Disease caused by Synchitrium endobioticum in Turkey
E. Cakir, Plant Protection Central Research Institute, Bagdat Caddesi No 250, P.K 49, Yenimahalle, 06172, Ankara, Turkey. Accepted for publication 29 Mar 2005.

During October 2003, Potato (_Solanum tuberosum_) wart disease (PWD) was detected for the 1st time on potato tubers in Aybasti county (Ordu province in Black Sea Region), a non-economically important potato growing district. In the same year, the disease was also found in Nigde and Nevsehir, 2 commercially-important potato growing provinces in central Anatolia. The potato varieties Agria, Donella, Granola, Marfona and Russet Burbank grown in Nigde and Nevsehir provinces were affected with the disease in very low percentages (< 1 percent of all plants). In Ordu province, only a local variety, grown for home consumption, showed disease symptoms.

Diseased plants exhibited typical symptoms on tubers that ranged from mild, small to severe, large warts that completely transformed tubers into a dark mass. Galls of various colors, including shades of green, yellow, but
mostly brown, appeared on tubers by the end of the season. Summer and winter (resting) sporangia were observed from galls of different colors. Resting sporangia were typical of the fungus _Synchytrium endobioticum_
(Se), having irregularly shaped, dark brown walls. They were aseptate, light golden-brown, thick-walled, smooth, 40-50 mm in diameter and spherical to ovoid in shape. Resting sporangia were isolated from infected tubers and soil surrounding infected plants using a method developed.

Pathogenicity of the causal agent was proven by the Glynne-Lemmarzalh method by inoculating the potato sprouts at 1-2 mm long with some fresh wart tissue and incubating the plants at 18 ± 1 C. Sporangia were re-isolated from the warts observed 2 months later. Non-inoculated controls were symptomless.

PWD is now present in neighboring potato fields covering 907.7 and 23.3 ha in Nevsehir and Nigde provinces, respectively, on land covering approximately 10 ha in Ordu province.

This is the 1st report of PWD in Turkey. The Ministry of Agriculture has been employing the EU (1969) Council Directive 69/464 of 8 Dec 1969 on control of PWD. Disease surveys for this pathogen are continuing in Turkey.

References:

Glynne MD, 1925. Infection experiments with wart disease of potatoes, _Synchytrium endobioticum_ (Schilb.) Per. Annals of Applied Biology 12, 34-60.

Hampson MC, Thompson PR, 1977. A quantitative method to examine large numbers of soil samples for _Synchytrium endobioticum_, the cause of potato wart disease. Plant and Soil 46, 659-664.

Lemmerzahl J, 1930. A new simplified infection procedure for testing potato cultivars for wart resistance. Zucher 2, 288-297.

Walker JC, 1983. _Synchytrium endobioticum_. CMI Descriptions of Pathogenic Fungi and Bacteria. No 755. Wallingford, UK: CAB International.

--
ProMED-mail
<promed@promedmail.org>

[The most likely way PWD entered Turkey was by an accidental introduction of wart-infected potato or by contaminated soil or equipment. PWD has spread to most regions of the world where potatoes are cultivated.
_Synchitrium endobioticum_ affects cultivated potato and a number of wild _Solanam_. It was once the most serious disease of potato in the UK but has now been controlled by statutory measures and the development of "immune" varieties.

It still poses a serious threat to potato production, because the spores of the fungus can remain viable in contaminated soil for many years. New strains of the fungus, capable of attacking potato varieties that were previously resistant, have developed in several European countries. Preventing spread of these strains to the UK is especially important.

Links:
<http://www.defra.gov.uk/planth/pestnote/pwd.htm> <http://www.plantdepommedeterre.org/eng/disease/chamg3.htm>
- Mod.DH]