Effect of different straw management practices on yields of continuous spring barely

Field experiments were conducted in the maize-growing region on heavy gleic fluvisol from 1974 to 2000. Three variants of straw management (straw harvested, incorporated into soil and burned), two variants of soil tillage (conventional plough tillage to 0.22 m, shallow disc tillage to 0.12-0.15 m) and three variants of fertilization (30, 60 and 90 kg N.ha-1) were studied. After conventional tillage, the highest yield was obtained in the variant with burned straw (5.50 t.ha-1), followed by the variant with straw incorporated into soil (5.40 t.ha-1) and the lowest after harvested straw (5.01 t.ha-1). At shallow tillage, lower yields were assessed in all variants of straw management in comparison with conventional tillage (after straw burning 5.07 t.ha-1, incorporation into soil 4.66 t.ha-1 and harvest 4.54 t.ha-1). The ranking of variants was identical to that in inversion tillage; however, the yield increased more after straw burning in comparison with its incorporation into soil. Yields increased regularly along with increasing rates of nitrogen. If long-term effects of straw incorporation on yields and yield trends were evaluated (in comparison with straw harvest), statistically significant decrease in yields was assessed after shallow in contrast with increase in yields after deeper straw incorporation.