EFFECT OF VARIOUS SYSTEMS OF TILLAGE ON WINTER BARLEY YIELD, WEED INFESTATION AND SOIL PROPERTIES

A field experiment was performed to evaluate the yield of winter barley, weed infestation, and soil properties in various systems of tillage and crop rotation The following experimental factors were examined: tillage systems (TS): 1) CT - conventional tillage, 2) RT - reduced tillage, 3) NT - no-tillage; and crop rotation (CR): 1) winter wheat - winter barley, 2) pea - winter barley. Shallow ploughing and pre-sowing ploughing were performed in CT, cultivation in RT and glyphosate only was used in NT. The study found the highest barley grain yield in CT after pea, whereas the lowest one - in NT after wheat. A higher number and mass of weeds per m 2 was determined in RT than in CT and NT systems. Also the number and mass of weeds were found to be more affected by TS than by CR. The soil sampled from NT plots contained more organic C than that collected from RT and CT plots, and more total N than soil samples collected from CT plots. Higher contents of organic C and total N were also found in the soil from plots wherein barley was sown after pea compared to the soil from plot wherein barley was grown after wheat.