Effect of water stress on the growth of Arachis pintoi plants under different nitrogen levels

The objective was to evaluate the growth of Arachis pintoi fertilized with nitrogen and water deficiency conditions. The study was developed in a 4 × 4 factorial arrangement with four nitrogen levels (0, 40, 80 and 120 kg N/ha) and four irrigation levels (25, 50, 75 and 100% of field capacity), in a completely randomized experimental design, with four replications. High doses of N benefited the production of root shoots while the root increased its production at a dose of 40 kg N/ha. The number of green and senescent leaves were influenced by N fertilization and the water regime, where higher doses of N provided greater total number of green leaves (364 leaves/pot) and the limitation of water resulted in a greater number of senescent leaves (78 leaves/pot). Observing the maximum point, the water regime of 90% of field capacity and 120 kg N/ha favored leaf appearance rate of 1.2 leaves/day and less phyllochron (4.6 days/leaf) at 85% of field capacity and 115 kg N/ha. The dose of 120 kg N/ha resulted in ultimate greater width (1.4 cm) and length (2.4 cm) of the leaf at 100% of field capacity. The final length of stolons showed quadratic effect for N, having greatest length (58.1 cm) at 75 kg N/ha and 100% of field capacity.