Effect of cover crops on emergence and growth of carrot (Daucus carota L.) in no-plow and traditional tillage

The aim of the experiment was to determine the influence of cover crop biomass incorporated into the soil at different times and using different treatments on carrot emergence and growth. 7 species of cover crops were included in the study: Secale cereale, Avena sativa, Vicia sativa, Sinapis alba, Phacelia tanacetifolia, Fagopyrum esculentum, and Helianthus annuus. Number of emerged carrot plants significantly depended on the cover crop used and on the method of pre-winter and spring pre-sowing tillage. Carrot emerged best after a rye or oats cover crop. Regardless of the cover crop species used, the largest number of carrots emerged in cultivation on ridges. In other variants of no-plow tillage, number of seedlings was significantly lower and did not differ from that under traditional plow tillage. The highest leaf rosettes were formed by carrot growing after a rye or oats cover crop. The highest rosettes were produced by carrots in the treatments where tillage was limited to the use of a tillage implement in spring and the lowest ones after pre-winter plowing. The effect of tillage on the emergence and height of carrot leaves largely depended on weather conditions in the successive years of the study. The largest number of leaves was found in carrots grown after a buckwheat cover crop and in cultivation without cover crop, while the smallest one after phacelia and white mustard. Carrots produced the largest number of leaves after a sunflower cover crop and the use of a tillage implement in spring, while the number of leaves was lowest when the mustard biomass was incorporated into the soil in spring. The use of cover crops significantly increased the mass of leaves produced by carrot as compared to the cultivation without cover crop. The largest mass of leaves was produced by carrots grown after the phacelia and mustard cover crops. Conventional plow tillage and pre-winter tillage using a stubble cultivator promoted an increase in the mass of carrot leaves.