Georgian Scientists/ . 6 N 3, 2024 314 Georgian Scientists Vol. 6 Issue 4, 2024 https://doi.org/10.52340/gs.2024.06.04.27 1; 2; 3; 4; 5 1 , . : 599 28 52 10; : t.tsetskhladze@bsu.edu.ge; Orcid: 0000-0001-7180-0652; 2 , , . :l.gorgiladze@bsu.edu.ge ; : 593456044; Orcid: 0000-0001-5052-6543; 3 , , : 599285275; - :k.natsarishvili@bsu.edu.ge; Orcid: 0000-0001-8745-2277; 4 . , : 577179135, : k.sikharulidze@bsu.edu.ge, Orcid: 0000-0002-4201-8925; 5 . . : 555773077, - : Ketevan.memarne@bsu.edu.ge; Orcid: 0009-0002-9152-7555 (Solanum tuberosum L.) , . . , , . Alternaria solani Sorauer (Ell. et Mart.) Sor. (syn. Macrosporium solani Ellis & Martin) Alernaria alternata (Fries.) Keissler (syn.A.tenuis Nees.). 2022-2023 , , , , . Georgian Scientists/ . 6 N 3, 2024 315 , ( 2017, . .1985 ). , 10 , , . ( , . 2011). (Mayee and Datar,1986; Gondal..2012). , (R) : ), ). (MR) ); (S) (MS) . : ( ), ( ) ( ). (MR) : ( ), ), ( ). : ) : - . Alernaria alternata - ( ), ) Alternaria solani Sorauer . , Alernaria alternata , Alternaria solani Sorauer . , . : , , , , . (Solanum tuberosum L.) . . , , , . 2021 376 (FAO, 2023). Georgian Scientists/ . 6 N 3, 2024 316 . , , , 1000-2500 , 1981, , 2009). “ 2022 , 198.9 . , , : - 129.8 , - 35/1 , - 14 , -10.1 , - 2,1 , - 3.7 , - 4.1 . 2022 11.6 , (50-60 ) ,2023). , . , , . Alternaria solani Sorauer (Ell. et Mart.) Sor. (syn. Macrosporium solani Ellis & Martin) Alernaria alternata (Fries.) Keissler (syn.A.tenuis Nees.) (Rotem,1994; Simmons,2007, .,2011, ,2011, . 2020, ., 2010) , . , , . (Van der Waals et al., 2001, , 2005). 8-32 o C . 25–27°C (Vandecasteele, M. 2019, Kirk W., 2012). . (80-86%). , . , 3 . (Hooker W. J., 1981,Adams SS. et al. 1990) Georgian Scientists/ . 6 N 3, 2024 317 Alternaria solani Sor. 40-50% (Vandecasteele M.,2019, . .,1973, . . ., 2010). 70-80% (Adams et al .,1990, Jansky et al., 2008, . . 2020, Xue, W. et al. 2019). , , . , , , (Streit E. et al.,2013 ,Vandecasteele M,2019, . ., 2011, Rotem J. 2004. .2020). , ( . . 2015, Tsetskhladze Ts. et al., 2015). (Abuley,IK. et al., 2017), , , , . , , (Jansky SH. et al.,2008, . . 2020,Xue et al.,2019). , . , , (Demir S., et al .2002). . , . 2022-2023 . , , ( , #5(13). ( .1). Georgian Scientists/ . 6 N 3, 2024 318 .1. # 1. , , 2. , , 3. , , 4. , 5. , 6. , 7. , 8. , 9. , , 10. , 11. , 12. 13. , Georgian Scientists/ . 6 N 3, 2024 319 14. , , 15. 16. 17. 18. 19. , 20. , 21. , , 22. , 23. , , , 24. , 25. , 26. , 27. , Georgian Scientists/ . 6 N 3, 2024 320 28. , 29. , 30. , 31. - 32. 33. 34. - 35. , 36. 37. , 38. , 39. ( - 75X 25 , 10-12 ). ( , 2017, , . 1985). (90 ), (91-100 ), (101-110 ), - (111-120 ) ( 121 ). . Georgian Scientists/ . 6 N 3, 2024 321 , 10 , , . : P=n/N.100, P (%), n - ; N - . ,2011). , (Mayee and Datar ,1986; Gondal..2012). ( . 2). 2. . (%) 0 0-0 % ( )HR 1 0-5% R 2 6-20 MR 3 21-40 MS 4 41-70 S 5 >70 HS ANOVA- (ANOVA (Analysis Of Variance) Calculator | One-Way ANOVA Calculator. ( . .3). Georgian Scientists/ . 6 N 3, 2024 322 3. , 2022-2023 . 2022-2023 . 200C - 300C . , 76-85% ( .3), . , A. Solani . 40-60% . A. Alternata . (80-100%), . ( . .1). / ,0C , % , >1 />52022 20 ± 3.05 79 ± 2.08 28.56 ±9.46 14/7 20 ± 4.04 83.66 ± 1.85 14.4 ±13.8 19/8 24.3 ± 1.85 85 ± 0.57 41 ± 26.83 25/15 22.6 ± 0.66 87.66 ± 5.54 28.4 ± 19.28 21/6 30.6 ± 3.66 85.33 ± 1.66 7.53 ± 7 21/2 23.53± 1.96 84.13 ± 1.43 23.97 ± 13.15 2023 25 ± 0.57 76.33 ± 0.66 28.56 ± 9.46 20/8 20.66 ± 3.48 83 ± 0.57 14.4±13.8 23/7 24.66 ± 0.66 84.66 ± 2.40 40 ± 26.83 24/11 26.66 ± 0.66 82.66 ± 2.60 28.4 ± 19.28 11/5 27.33 ± 0.66 83.75 ± 1.03 7.53 ± 7 10/3 24.86 ± 1.16 82.08 ± 1.47 17.11 ±4.85 Georgian Scientists/ . 6 N 3, 2024 323 .1. : , : ( ), ( ) - ( ) ( ) ( . .2). .2. ( - - ). : ), ( ), ), ( ) ( ). : ( ) ( ), ), ( ), , ( , ). ( . 4). Georgian Scientists/ . 6 N 3, 2024 324 .4. A.solani - A. alternata , # A.solani) A. alternate) . , % . , % 1. 60 4 S 25-30 3 MS 2. 40-50 4 S 25 3 MS 3. 30-50 4 S 30-60 4 S 4. 45-50 4 S 60-80 5 HS 5. 45-50 4 S 50-80 5 HS 6. 40-45 4 S 35-45 4 S 7. 50 4 S 50 4 S 8. 45 4 S 55 4 S 9. 5-10 2 R 5-10 2 R 10. 70 5 HS 80 5 HS 11. 25 3 MS 60-70 4 S 12. 35 3 MS 60-70 4 S 13. 25 3 MS 40 4 S 14. 30-35 3 MS 80 5 HS 15. 20-30 3 MS 10-20 2 MR 16. 35-40 3 MS 60 4 S 17. 40 3 MS 50-60 4 S 18. 35-40 3 MS 30-40 4 S 19. 25-40 3 MS 20 2 MR 20. 35-40 3 MS 50 4 S Georgian Scientists/ . 6 N 3, 2024 325 21. 20-40 3 MS 5-20 2 MR 22. 35 3 MS 40 4 S 23. 10-15 2 MR 40 3 MS 24. 25-35 3 MS 80 5 HS 25. 35-60 4 S 50 4 S 26. 30-35 3 MS 50 4 S 27. 30-60 4 S 50 4 S 28. 60 4 S 60-65 4 S 29. 30-35 3 MS 30 3 MS 30. 35 3 MS 25-30 3 MS 31. 30-35 3 MS 15-20 2 MR 32. 1-5 1 R 5 1 R 33. 35 3 MS 30-35 3 MS 34. 5 1 R 10 2 MR 35. 35 3 MS 35 3 MS 36. 30 3 MS 30 3 MS 37. 50-60 5 S 40-45 4 S 38. 20-25 3 MS 20-25 3 MS 39. 30-35 3 MS 25 2 MS , 2022-2023 . . - Alternaria solani Sorauer (Ell. et Mart.) - (R) : , . (MR) . (S) (MS) . Georgian Scientists/ . 6 N 3, 2024 326 - Alernaria alternata (Fries.) Keissler - (R) : , , . (MR) : , , , . : , . Alernaria alternata : , Alternaria solani Sorauer . , Alernaria alternata , Alternaria solani Sorauer - . , . , ; 1981. . „ ”. .369-401 , . 2009. , , .67- 77 , ., , ., , . 2015. . #34 , . . 204-207 , #5(13). , 2012 .12. 07 , , , ., , . 2017. , , 169 . , ., , ., , . 2011. . . .: . 47 . , . 2011. Alternaria. . . - , 2011. , . ., , . ., , . . 2020. Alternaria ( ), , 56, 3, . 223–241. Georgian Scientists/ . 6 N 3, 2024 327 , ., , . ., , . . . Solanaceae / . 1973. 15. . 160—167. , . . 1985. ( ). , ., , ., , . 2020. . , 103(2), . 99– 104 , . ., , ., . . 2005. . : 696 . , . ., , . ., , . . 2010. B , Alternaria, solanaceae, · . 44 , . 2, 2010. Abuley, IK., Nielsen, BJ. 2017. Evaluation of models to control potato early blight (Alternaria solani) in Denmark. Crop Prot 102:118 128. https://doi.org/10.1016/j.cropro.2017.08.012 Adams, SS., Stevenson, WR. 1990. Water management, disease development and potato production. American Journal of Potato Research 67:3-11 Datar, V.V., Mayee, CD. 1981. Assessment of loss in tomato yield due to early blight. Indian Phytopathology 34: 191-195 Demir, S., Levent, R., 2002. Reaction of different potato cultivars against to early blight disease // J. Turcish Phytopathol., 31, 2, p. 97–103. Gondal, AS., Ijaz M, Riaz, K., and Khan, AR, 2012. Effect of Different Doses of Fungicide (Mancozeb) against Alternaria Leaf Blight of Tomato in Tunne. J. Plant Pathol Microb. 3:3 http://dx.doi.org/10.4172/2157-7471.1000125 Hooke, W. J., Editor Compendium of Potato Diseases, Published by the American Phytopathological Society , 1981, 43-45. Jansky, SH. Simon, R., Spooner, DM. (2008) A test of taxonomic predictivity: resistance to early blight in wild relatives of cultivated . Phytopathol 98(6):680–687. https://doi.org/10.1094/PHYTO-98-6-0680 Kirk, WW., Abu-El Salem, FM., Muhinyuza, JB., Hammerschmidt, R., Douches, DS. et al. 2005. Evaluation of potato late blight management utilizing host plant resistance and reduced rates and frequencies of fungicide applications. Crop Prot 24: 961-970. Mayee CD, Datar VV. Phytopathometry. Tech. Bull.1.Univ. Press. Marathwada Agriculture University, Parbhani (M.S.), 1986, 186. Georgian Scientists/ . 6 N 3, 2024 328 Rotem, J. 2004. The genus Alternaria:biology, epidemiology and pathogenicity. American Phytopathological Society Press. St. Paul, MN, USA Simmons, E. G. Alternaria: an Identification Manual. Utrecht, 2007. 775 p Streit E., Schwab C., Sulyok M., Naehrer K., Krska R., Schatzmayr G. // Toxins. 2013. V.5. 3. P. 504–523 Tsetskhladze. Ts., Sikharulidze, Z., Muradashvili, M., Sikharulidze K.T. 2018. Screening of tomato varieties for resistance to major fungal diseas and bacterial wilt. Plant Protection and Quarantine, Kiev 2018. ISSUE 64, UDC:631.526, ISSN 1606-9773, p.262-267 Vandecasteele, M. (2019). Characterization of Alternaria species on potato: towards a better understanding of the fungal genus in Flanders. PhD Thesis, Department of Plant Sciences, Ghent Van der Waals, J.E., Korsten, L. and Aveling, T.A.S. (2001). A review of early blight of potatoes. Afr. J. Plant Prot. 7(2): 91–102. Vandeveire, M. (1991). The selective insecticide Xue, W., Haynes, K. G., & Qu, X. (2019). Characterization of early blight resistance in potato cultivars. Plant Disease, PDIS-05-18-0794-RE, PDIS-05-18-079 : Global Potato Statistics - Latest FAO Data Published online: Jan 29, 2023 FAO. 2023. World Food and Agriculture – Statistical Yearbook 2023. Rome. https://doi.org/10.4060/cc8166en https://www.fao.org/documents/card/en/c/cc8166en Netherlands_catalogue_of_potato_varieties_2011_Nivap https://www.agricopotatoes.com/overview?segment=SEG_Processing https://kartofan.org/category/sorta http://www.europlant.biz/no_cache/en/sortensuche-ergebnis/ https://cipotato.org/blog/cip-launches-georgia/ https://www.europlant.biz/en/list-of-varieties/ https://www.europotato.org/varieties http://potatoassociation.org/industry/varieties/ ANOVA (Analysis Of Variance) Calculator | One-Way ANOVA Calculator https://www.geostat.ge/media/54292/soflis_meurneoba_2022.pdf Georgian Scientists/ . 6 N 3, 2024 329 Resistance of Local and Introduced Varieties of Potato to Alternaria in Western Georgia Tsetskhladze Ts., Gorgiladze L., Natsarishvili K., Sikharulidze K., Memarne K. Batumi Shota Rustaveli State University, Institute of Phytopathology&Biodiversity, Batumi, Georgia Abstract Introduction and research objective. Potato is one of the important crops due to its versatile use and valuable nutritional properties. According to the United Nations Food Security Program, it is named the main subsistence food product after bread. Diseases are one of the limiting factors of potato yield. Alternaria causes important losses and stands out for its wide distribution among them. Alternarias species can be found everywhere where representatives of the Nightshade family are grown. Diseases Early blight (causal agent: Alternaria solani Sorauer (Ell. et Mart.) Sor. (syn. Macrosporium solani Ellis & Martin) and Brown Leaf Spot (causal agent: Alernaria alternata (Fries.) Keissler (syn.A.tenuis Nees.) are distinguished by their spread and harmfulness in the conditions of Western Georgia. The research aimed to identify resistant varieties to these diseases from thirty-six introduced potato varieties, as well as three samples from international nurseries adapted to Georgian conditions. Methodology. To achieve the goal, in 2022-2023, potato samples were planted in Kobuleti, on the experimental field of the Institute of Phytopathology and Biodiversity of BSU, for further testing under a natural infection background, according to the generally accepted methodology [2,3]. Results. The study showed that among the tested samples, a resistant reaction (R) to Early blight was found in the varieties: Milva (Netherlands), Slavyanka, and Glazurnaya (Ukraine). A moderately resistant reaction (MR) was shown by the Fabula variety (Netherlands); the remaining samples had a susceptible (S) and moderately susceptible (MS) reaction to the pathogen. The following varieties turned out to be resistant to Brown Leaf Spot: Milva (Netherland), Alvara (Germany), and Glazurnaya (Ukraine), and moderately resistant (MR) - Slavyanka (Ukraine), Nevskaya (Russia), Pekaro and Jelly (Netherland). Three varieties were found to be resistant to both diseases: mid-early Milwa (Dutch), Ukrainian varieties Glazurnaya (mid-early), and Slavyanka (mid-late). Some cultivars, moderately resistant to Alernaria alternata - Alvara (Germany), Pecaro, and Jellie (Netherland) were moderately susceptible to Alternaria solani Sorauer. A different reaction was also shown by the Nevsky , which was moderately resistant to Alernaria alternata, and moderately susceptible to Alternaria solani Sorauer. Conclusion. Resistant and medium-resistant potato varieties (Milwa, Glazurnaya, Slavyanka), identified from tested samples can be used as sources of resistance to Alternaria. Key words: Potato, Alternariose, Intensity, Distribution, Resistance.