Physico-chemical attributes of no-till Brassica crops cultivated after various cover crops

Cauliflower and cabbage require high amounts of nutrients in short periods of time; however, the intensive use of inorganic fertilizers can cause nutritional imbalances in these crops and reduce the quality of the final product. This study evaluated the chemical composition and yield of no-till cauliflower and cabbage grown on residues of various cover crops in Uberaba, Minas Gerais State, Brazil. The experimental design was randomized blocks with four cover crops (sunn hemp, brachiaria, pearl millet and fallow) and two main crops (cauliflower and cabbage). The treatments were evaluated on plots of 20 m2 with four replications. The following traits were analyzed after harvest: moisture (MO), ash (ASH), lipid (LIP), crude fiber (CF), protein (PTN), carbohydrates (CARB), total soluble solids (TSS), total titratable acidity (TTA), pH, ascorbic acid (AA), head fresh weight (HFW), head dry weight (HDW) and yield. Cauliflower cultivated on sunn hemp residues produced high levels of LIP, PTN, CARB, TSS and TTA, whereas cauliflower cultivated on brachiaria and millet residues demonstrated high AA levels when compared to the treatment with sunn hemp residues. In the aerial part, cabbage presented significantly higher levels of CARB, TTA and AA when cultivated on brachiaria residues, whereas PTN levels were higher on sunn hemp residues. The cultivation of cauliflower and cabbage on cover crop residues affected positively most of the chemical attributes of the evaluated crops when compared to the fallow treatment, although the highest yield and AA levels were observed when the crops were cultivated on brachiaria residues.