The impact of no-tillage cultivation and white mustard as a cover crop on weed infestation and yield of carrot and red beet

In a two-year field experiment, no-tillage cultivation using white mustard ( Sinapis alba L. ‘Bardena’), 30 kg ha −1 , as a cover crop did not influence emergence of red beet ( Beta vulgaris L. ‘Czerwona Kula REW’) and had a favorable effect on emergence of carrot ( Daucus carota L. ‘Berlikumer 2 – Perfekcja REW’). However, further growth of both vegetables was significantly slower under no-tillage cultivation. Both vegetables produced a higher yield of roots and the diameter of these roots was bigger under conventional cultivation. The effect of cultivation method on the content of total nitrogen, phosphorus, potassium, calcium and magnesium in carrot and red beet leaves varied, while the content of dry matter, monosaccharides and total sugars was significantly higher in the roots of both vegetables harvested under no-tillage cultivation. The number of weeds growing on no-tilled plots covered with mustard mulch 4 weeks after seed sowing was lower by about 75%, but their fresh weight was higher more than 6 times in comparison to that under conventional cultivation. This was caused by the emergence of wintering and winter hardy weeds in places not covered by mustard plants in the autumn of the year preceding the cultivation of vegetables. Next year, they started to grow in the early spring and some of them produced a considerable amount of fresh weight and attained the flowering stage in the middle of April.