Effects of Catch Crops and Tillage System on Weed Infestation and Health of Spring Wheat

The paper presents results of research on weed infestation and health of spring wheat grown in the three-year monoculture. The field experiment was carried out on loess soil, classified as “good wheat complex” (soil class II). The first experimental factor was the type of Catch Crop (CC): (a) Object control, no catch crop, (b) White mustard, (c) Tansy phacelia, and (d) Mixture (bean+spring vetch+oat). The second factor was Tillage System (TS): (a) Plow Tillage (PT), and (b) Conservation Tillage (plowless tillage, CT). It was proved that catch crops (especially white mustard) could be an effective way to reduce the negative effects of growing spring wheat in monoculture. This causes both the reduction of the number and weight of weeds in the field, as well as reduction of the proportion of fungal pathogens infecting wheat plants. The regenerating effects of catch crops in the three-year wheat monoculture were more effective under conventional tillage conditions compared to conservation tillage. It also showed that the conservation tillage system had significant effect on increasing the quantitative indicators of weed infestation of wheat and increasing the number of weed seeds in the soil. Conventional tillage with plowing resulted in smaller biodiversity of weed species than conservation tillage system. Tillage method did not cause differentiation degree of infection of wheat stem base by a fungal disease complex. Catch crops, in particular white mustard, proved to be an effective method to reduce the degree of infection of spring wheat by fungal pathogens.