COVER CROPS AND SOIL-BORNE FUNGI DANGEROUS TOWARDS THE CULTIVATION OF SALSIFY (Tragopogon porrifolius var. sativus (Gaterau) Br.)

Salsify has a remarkable taste and nutritious values. It is a rich source of inulin - a glycoside which has a positive effect on human and animal organisms. The paper presents studies on the species composition of soil-borne fungi infecting the roots of Tragopogon porrifolius var. sativus cultivated with the use of oats, tansy phacelia and spring vetch as cover crops. In a field experiment the cover crops formed abundant green mass before winter and it constituted a natural mulch on the surface of the plough land. It was managed in two ways: I) mixed with the soil as a result of spring ploughing, or 2) mixed with the soil as a result of pre-winter ploughing. The conventional cultivation of salsify, i.e. without cover crops, constituted the control. The studies established the number and health status of four-week-old salsify seedlings and roots with necrotic signs. A laboratory mycological analysis made it possible to determine the quantitative and qualitative composition of fungi infecting the underground parts of Tragopogon porrifolius var. sativus. The emergences and the proportion of infected salsify seedlings varied and depended on the species of the mulching plant. The smallest number of infected seedlings was obtained after the mulch with oats, slightly more after the application of spring vetch or tansy phacelia as cover crops, and the most in the control. Regardless of the species of the mulching plant, the following were frequently isolated from the diseased seedlings and roots of salsify: Alternaria alternate, Fusarium culmorum, Fusarium oxysporum, Penicillium spp., Rhizoctonia solani and Sclerotinia sclerotiorum. Rhizoctonia solani and Sclerotinia sclerotiorum proved to be the most harmful towards the roots of salsify. The system of cultivation, i.e. performing spring or pre-winter ploughing, had no significant effect on the total population of fungi.