BIODIVERSITY OF FUNGI COLONIZING SCORZONERA (Scorzonera hispanica L.) CULTIVATED WITH THE USE OF BIOSTIMULANTS

Biostimulants are friendly to the soil environment and can effectively improve the plant growth and yielding. The aim of field and laboratory studies was to establish the effect of biostimulants on the growth and on the health status of Scorzonera hispanica L. plants. The field experiment was carried out in south-eastern Poland on Haplic Luvisol. The biostimulants were applied according to the manufacturers’ recommendations. Moreover, the biostimulants Asahi SL (active components: nitroguaiacolate and nitrophenolates), Beta-Chikol (a.s. – chitosan) and Bio-Algeen S90 (extract from seaweed Ascophyllum nodosum) were applied for the pre-sowing seed dressing of scorzonera cv. ´´Duplex´´. For comparison, the fungicide Zaprawa Nasienna T 75 DS/WS (a.s. – tiuram 75%) was used. Untreated seeds served as control. Moreover, the biodiversity of soil-borne fungi colonizing the roots of this vegetable was determined. The number of seedlings and the health status of scorzonera plants were determined during three growing seasons. In each year of the study, both scorzonera seedlings with necrosis symptoms on the roots and the infected roots obtained after scorzonera harvest were subjected to laboratory mycological analysis. The experiments showed that, the emergence and health status of scorzonera seedlings after the application of biostimulants, especially after Beta-Chikol, were significantly better than in the control. Asahi SL and Beta-Chikol were more effective than Bio-Algeen S90 in limiting the occurrence of fungi pathogenic towards scorzonera plants. Diseased scorzonera roots were most frequently colonized by Alternaria scorzonerae, Alternaria alternata, Rhizoctonia solani, Sclerotinia sclerotiorum and Fusarium spp., especially by Fusarium oxysporum. In conclusion, Asahi SL, Beta-Chikol and Bio-Algeen S90 can be recommended as effective biostimulants in field cultivation of Scorzonera hispanica.