Crescimento inicial de cultivares de amendoim (arachis hypogaea L.) submetidas a densidades de plantio

Abstract

The cultivated peanut species (Arachis hypogaea L.) is among the world's largest cultivated oilseeds. However, there is still no technical information on cultivars and planting densities for phytomass production. In this sense, the objective was to evaluate the emergence and initial growth of four peanut cultivars under different planting densities. The experiment was conducted in the municipality of Garanhuns-PE, in the agricultural years 2018/2019 in the dry season and under field conditions. The experimental design was a randomized block design with a 4x5 subplot scheme, with four cultivars (Runner IAC 886 and IAC 503 prostrate and BR1 and TATU ST standing erect) and submitted to five planting densities (8, 11, 14, 17 and 20 plants per linear meter). The emergence and initial growth in height (cm), number of leaves and diameter (mm) of the main stem at 28, 35 and 42 days after planting were evaluated. For the qualitative factor (cultivars), the data were submitted to analysis of variance and the means were compared by the Tukey test (significance of 5%), using SISVAR software. For the quantitative factor (densities), the regression analysis was used. Higher plant densities resulted in a lower percentage of emergence, mainly for the cultivar IAC 886. The cultivar IAC 503 obtained the highest percentage in the density of eight plants per linear meter. At 28 and 35 DAP, all cultivars increased their height, number of leaves and diameter as a function of the increase in planting density. At 42 DAP, the diameter did not differentiate between the cultivars, when it coincided with the beginning of flowering. Densities of 17 and 20 seeds per linear meter result in lower percentages of emergencies. At 35 days after peanut planting, higher values of height, number of leaves and diameter of plants are obtained with densities of 17 and 20 plants per linear meter in the agreste Pernambuco. The diameter of low - growing cultivars does not differ from cultivars of erect size at 42 days after planting.