This research aimed to evaluate the growth and macronutrients accumulation of carrot cultivars as a function of two planting times, under high temperatures in the Brazilian semi-arid. The experiments were laid out in randomized blocks design, with ten treatments and four repetitions. Treatments consisted of ten carrot cultivars sowed in two planting times. The characteristics evaluated included: plant growth (plant height, number of leaves, plant dry matter accumulation, average fresh mass of the root) and nutrient accumulation in plant, leaves and root (N, P, K, Ca and Mg). Plantâ€™s average height ranged from 42.53 cm (Melinda) to 49.25 cm (Nativa); the highest plant dry matter was obtained by the cultivars BRS Planalto (12.36 g) and Kuronan (12.18 g); the average number of leaves was the lowest in the cultivars Melinda and Nativa: 8.64 and 7.64 leaves plant-1. The average root weight decreased, for almost all cultivars, from Planting Time 1 to Planting Time 2. The accumulation of nutrients varied accordingly to the planting time and cultivar. In decreasing order, the nutrients that were accumulated the most in the plant were: K>N>P>Ca>Mg. The hybrid cultivars presented nutritional demand either similar or lower than that of the open pollinated cultivars, despite their lower dry matter content in the leaves. This characteristic points towards the higher efficiency in nutrient utilization by the hybrid carrot cultivars.
Keywords: Daucus carota L.; genotypes; macronutrients; adaptability.