Beet Crop under Different Fertilization and Nitrogen Fertigation in Protected Environment

Chemical fertilizers have been increasingly used in agriculture. The application of these nutrients via irrigation water has been evaluated in order to obtain productive results in agricultural yield. The objective of this research was to evaluate the effect of nitrogen (N) doses, applied by fertigation and associated with different types of basal fertilization, on the growth and production of beet. The experiment was conducted at the Federal University of Campina Grande (UFCG), in a protected environment belonging to the Academic Unit of Agricultural Engineering (UAEA). The adopted statistical design was completely randomized blocks, with three replicates, and the factors were arranged in a 5 × 3 factorial scheme, corresponding to five N doses (0, 50, 100, 150 and 200 mg dm-3 of soil), and three types basal fertilization (soil without fertilizer, earthworm humus, earthworm humus + NPK). At 45 days after transplanting, the number of leaves per plant, plant height, stem diameter, leaf area, green intensity, bulb diameter, stem length, bulb fresh weight, bulb dry weight and total soluble solids (°Brix) were quantified. Both Soil basal fertilization significantly influenced beet growth and production, and the treatment with earthworm humus and earthworm humus + NPK led to the best results for the analyzed variables. The highest N dose promoted the best performance for stem diameter and content of total soluble solids (°Brix).