THE EFFECTIVENESS OF IMMUNOLOGICAL EVALUATION OF RESISTANCE OF THE WHITE CABBAGE LINES TO PLASMODIOPHORA BRASSICAE WOR. AGAINST ARTIFICIAL INFECTION BACKGROUND

Clubroot disease (causative organism Plasmodiophora brassicae Wor.) is among the most economically important and harmful diseases of the cole crops, and the damage due to this disease may reach up to 50-75% of the yield and even 100% in epiphytotics years. Even resistant varieties become susceptible over the years, because of appearance of the new pathogen races and change of climatic conditions in the main growing areas of the crop. In this context the Laboratory of Plant Immunity and Protection, of Federal State Budgetary Scientific Institution “Federal Scientific Vegetable Center” implements continuous phytoimmunological evaluation of collection and selection specimens and also directional material rather than just annual monitoring of causative organism dissemination in order to find new resistance sources. For this purpose an artificial infection background is used: compost obtained from decomposed nodules on the cabbage roots affected by clubroot disease (infection load 105-106 spores/cm3). The resistance of white cabbage varieties was evaluated during the harvesting period using five-point score of the root system damage, which formed the basis for categorization into resistance groups. For the analysis of artificial background intensity and specimen ranking the individual plants of the white cabbage variety Slava 1305, which is a susceptibility standard, were randomly planted in the entire area of the infection background. The impact of atmospheric conditions in the study year on the results of phytopathological evaluation of cabbage selection specimens against the infection background is demonstrated. Under unfavorable conditions for pathogen development (2014) the most specimens (74%) were categorized as relatively resistant, while in favourable for pathogen year 2015 relatively resistant specimens comprised only 5% of the total number of studied specimens. Since the same specimen may show different level of resistance depending on the year conditions, the stability of character manifestation is the important criterion for identification of the resistance resources. Phytopathological evaluation aimed on selection of clubroot-resistant forms in the Moscow region should last for at least three years even with the use of infection background. Long-lasting evaluation showed that the strains No 234/15,140/14,216/17 exhibiting high resistance to clubroot against artificial infection background regardless of the year conditions are the most valuable for selection. The resistance of white cabbage selection varieties to clubroot disease was studied against the infection background.

1. Bondareva L.L. CONSECUTIVE CULTIVATION OF WHITE HEAD CABBABE HYBRIDS DEVELOPED AT VNIISSOK FOR VEGETABLE MARKET OF RUSSIA. Vegetable crops of Russia. 2017;(1):22-23. (In Russ.) https://doi.org/10.18619/2072-9146-2017-1-22-23

2. Boos G.V., Vlasova E.A. The use of Crop Research Institute genebank in the vegetable crop selection for resistance of the main diseases // Selection for resistance to the main diseases of the vegetable crops / M., 1984.

3. Monakhos G.F., Jalilov F.S., Monakhos S.G. Evaluation of the cabbage crops resistance to clubroot /Study guide, М.,2009. 23 p.

4. Gerasimov B.V., Osnitskaya E.A. Pests and diseases of the vegetable crops / M., Selkhosizdat, 1961. 79 p.

5. Sokolova L.A., Tupenevich S.M. Cabbage clubroot / L., Kolos, 1974. 74 p.

6. Kvasnikov B.V. Selected Works /M., 1992.

7. Kvasnikov B.V., Belik T.A. The procedure of evaluation of the cabbage varieties resistance to Clubroot disease /M. VASHNIL, 1970. 16 p.

8. Maslova A.A., Ushakov A.A., Startsev V.I., Bondareva L.L. THE RESULTS OF STUDY OF CABBAGE PLANT RESISTANCE TO PLASMODIOPHORA BRASSICAE. Vegetable crops of Russia. 2014;(1):68-71. (In Russ.) https://doi.org/10.18619/2072-9146-2014-1-68-71

9. Andreev Ju.M., Elements of growing practice of the pe-tsai cabbage resistant to finger-and-toe disease //Vestnik ovoschevodstva, 2011. №2. P.14-17.

10. Samokhvalov A.N., Rogachev Ju.B., Ignatov A.N. Best practice of accelerated evaluation and selection of the cabbage parent material for group resistance to clubroot and bacteriosis /M., 1995.

11. Samokhvalov A.N. Methods of the vegetable crop selection to resistance to the diseases /M.,1997. 138 p.

12. Vasilchenko V.V., Smirnov A.N. Short-term viability of the causative agents of late blight and early blight of potato under laboratory conditions // Achievements of science and technology agribusiness. 2018. Vol. 32.No.6. P.49-52.

13. Kozar E.G., Blandinskaya O.A., Balashova I.T. Characteristics of grey mold lesions in some varieties of sweet pepper under conditions of plastic film greenhouse in Moscow region. // Proceedings of the international research and practice conference “State of the art and the prospects of the vegeculture innovative development”. Minsk: Samokhvalovich. 2014. P.137-145.

14. Pyshnaya O.N., Mamedov M.I., Belavkin E.G., Kozar E.G., Dzhos E.A., Matyukina A.A., Resistance of sweet pepper genotypes to abiotic stresses in grpwing conditions of low-capacity hydroponics. Agricultural biology. 2016. Vol. 51. №1. P.100-110.