Survival of Sclerotium cepivorum Sclerotia and Fusarium oxysporum Chlamydospores in Soil Amended with Cruciferous Residues

The use of cruciferous plant residues to reduce the amount of sclerotia of Sclerotium cepivorum and chla! mydospores of Fusarium oxysporum f[ sp[ lycopersici in soil was investigated[ Air!dried and crushed mustard "Brassica juncea# added to the soil e}ectively reduced the viability of fungal propagules[ Consequently\ the reduction of white rot of onion\ caused by S[ cepivorum and wild of tomato caused by F[ oxysporum was observed[ The addition of rapeseed "Brassica[ napus cv[ Bolko and B[ napus cv[ Gorczanski# residues to soil also resulted in a signi_cant decrease of number of S[ cepivorum sclerotia but the e}ect on F[ oxysporum chlamydospores was vari! able[ Introduction of the plant material increased the total number of bacteria\ spore!forming bacteria\ ~u! orescent pseudomonads\ actinomycetes\ and fungi in soil[ One year after the soil amendment\ the amount of spore! forming bacteria in treatments with cruciferous residues was higher as compared to the control soil without plant residues[ The possible contribution of the decomposition of plant residues and soil micro!organisms to the reduction of the pathogens population is discussed[