Effect of metabolites of the fungus Fusarium oxysporum (Schlecht.) Snyder & Hansen on plants of spring rapeseed and brown mustard plants of different resistance to Fusarium wilt

The aim of the research was to study the effect of metabolites of the fungus Fusarium oxysporum (Schlecht.) Snyder & Hansen on spring rapeseed and brown mustard plants of different groups of resistance to the Fusarium wilt. The effect of metabolites was studied using the culture fluid of the pathogen obtained by growing the mycelium of an isolate of F. oxysporum in flasks on Chapek's liquid nutrient medium for seven days. It was found that all seedlings placed in vessels with culture fluid of the pathogen showed symptoms of the disease (darkening of root tissues and wilting of seedlings) to varying degrees. Disease development in susceptible samples was two times higher than in resistant breeding sam-ples: in susceptible samples, it was high, reaching 62.3 and 60.5%, and in resistant samples, it was medium (30.0 and 38.5%, respectively). Metabolites of the fungus F. oxysporum, present in the culture fluid, showed highly toxic properties and had a negative effect on rapeseed and mustard seedlings, mostly from susceptible breeding samples. The different reaction in resistant breeding samples justifies the possibility of using pathogen metabolites to assess the resistance of spring rapeseed and brown mustard to Fusarium wilt under laboratory conditions.