Research on the formation of new virulent pathotypes of Synchytrium - - PowerPoint PPT Presentation

Research on the formation of new virulent pathotypes of Synchytrium endobioticum (Schilb.) Perc., the causal agent of potato wart disease.

Jarosław Przetakiewicz Plant Breeding and Acclimatization Institute – National Research Institute, Department of Plant Pathology, Laboratory of Qurantine Organisms, Radzików, 05-87 Błonie, Poland

Pathotypes in EPPO region.

• About 40 different pathotypes of the fungus were identified in

Europe (Baayen et al., 2006).

• New pathotypes have been detected recently: 38(N1) in Turkey

(Çakir et al., 2009) and 39(P1) in Poland (Przetakiewicz, 2015).

• New outbreaks have been observed in countries with a warmer

continental climate, such as Turkey, Georgia, Bulgaria or Greece (Çakir, 2005; Dimitrova et al., 2011; Gorgiladze et al., 2014; I. Vloutoglou pers. comm., 2015).

• Several Polish virulent isolates had the same profile as other ones

detected in other European countries

Polish map with marked districts where living spores of S. endobioticumweredetected.

Only winter sporangia in Bydgoszcz & Toruń districts Only winter sporangia in Żywiec district. Warted plants & winter sporangia Only winter sporangia in Grodzisk district

A map of Lesser Poland Province with marked communes where S. endobioticum still occurs.

Dębno Skawica S. Beskidzka Zawoja

• N. Targ
• Cz. Dunajec

B. Tatrzańska M. Podhalański

• R. Zdrój

Lesser Poland lies in the Vistula River catchment area.

Life cycle of S. endobioticum.

Differenti al cultivars Number of tested Rotten sprouts No reaction Laboratory assessment Total Mean Score Remarks Resistant Susceptible Resis tance grou p Classification 1 2 3 4 5 Evora 45 45 45 5.0 S2 Extremely susceptible Irga 45 45 45 1.0 R1 Extremely resistance Erika 45 45 45 4.0 S1 Slightly susceptible

Reaction of cv. Evora, Irga& Erikato pathotype 1(D1) 4 weeks after inoculation.

Reaction of cv. Erika, Irga& Evorato pathotype 1(D1) 4 weeks after inoculation (GL).

Warts from cv. Erika after the first passage.

• Pathotype

determination

• f the first

generation.

Warts from cv. Erika after the second passage.

• Pathotype

determination

• f the second

generation.

Warts from cv. Erika after the third passage.

• Pathotype

determination

• f the third

generation.

Warts from cv. Erika after the second passage.

• Pathotype

determination

• f the fourth

generation.

Step by step of modified Potoček’stube test.

Plastic rings are fixed using warm paraffin. Inoculation Incubation Visible proliferation

• n sprouts.

The warts ready for diagnostic.

Three generations of pathotype 1(D1) on cv. Erika (2013).

WS from p. 1(D1) WS from I generation WS from II generation I II III

Reaction of cv. Irga to pathotype pathotype1(D1) (left) and after tree generationson cv. Erika (right)–2 weeks after inoculation (GL, 2013).

I II III

Reaction of cv. Spuntato pathotype 1(D1) & warts from the 3rd generation selected on cv. Erika (GL, 2013).

Reaction of cv.Erika after 2 generations (2015).

Reaction of. cv. Irga& Combito warts from on warts of the 2nd generation selected on cv. Erika (GL, 2015).

Reaction of differential cvs. to isolates of S. endobioticum selected from 1(D1) on Erika after 2 generations (GL).

No Differential cultivars Isolates of S. endobioticum #E/15/1 #E/15/2 #E/15/3 #E/15/4 #E/15/5 #E/15/6 #E/15/7 #E/15/8 1Deodara + + + + + + + + 2Tomensa + + + + + + + + 3Eersterling + + + + + + + + 4Producent + + + + + + + + 5Combi + + + + + + + + 6Saphir

• 7Delcora

± ± ± ± ± ± ± ± 8Miriam

• 9Karolin
• 10Ulme
• 11Asche Sämling
• 13Desiree

± ± ± ± ± ± ± ± 14Talent + + + + + + + + 15Gawin

• 16Bałtyk

+ + + + + + + + 17Giewont + + + + + + + + 18Universal + + + + + + + + 19Blanik + + + + + + + + 20Irga + + + + + + + +

+ Positive reaction (big warts),

• Negative reaction (no warts),

±

Intermediate reaction (partially proliferation of sprouts),

Virulence profiles of different pathotypes of S. endobioticum.

+ Positive reaction (big warts),

• Negative reaction (no warts),

±

Intermediate reaction (partially proliferation of sprouts), Cultivar Virulence profiles of S. endobioticum pathotypes 1(D1) 2(G1) 6(O1) 8(F1) 18(T1) 2(Ch1) 3(M1) 39(P1) #/E/15 Deodara + + + + + + + + + Tomensa + + + + + + + + + Eesterling + + + + + + + + + Evora + + + + + + + + + Producent

• +

+ + + + + + + Combi

• +

+ + + + + + + Spunta

• +

+ + + + + + + Saphir

• +
• Otolia
• ±
• Delcora
• ±

+ + +

• +

± Miriam

• ±

+ ±

• +
• Karolin
• Ulme
• Asche Sämling

+ + + + +

• +
• Désirée
• ±

+ + +

• +

± Talent

• +

+ + + + + Gawin

• Bałtyk
• +

± + ± + + ± + Giewont

• ±

+ + + + + + Universal

• +

+ + + + + + + Blanik

• +

+ + + + + + Irga

• +

+ + + + + + + Nicola

• +

Conclusions

• Cultivation of slightly susceptible cultivars to pathotype 1(D1)

(in the fields infested by the spores of the fungus in regions with favorable climate for S. endobioticum) may leads to emergence of new virulent pathotypes.

• Under favorable conditions, the selection of virulent

pathotypes require 2-3 seasons (years).

• The same virulent pathotype can be selected from 1(D1) on

the specific cultivars many times in different regions.

Thank you for your attention