Componentes de produção e produtividade da cultivar de feijão-caupi, brs aracê em função da adubação e aplicação de bioestimulantes

Abstract

Cowpea (Vigna unguiculata L. Walp.) is a strategic legume for supplying vegetable protein, especially in Africa and in the Northeast and North regions of Brazil. Biostimulants have been widely used as synthetic or natural plant regulators, formed by chemical compounds, represented by amino acids, vitamins, nutrients and/or microorganisms. In this context, the objective of this research was to evaluate the effects of fertilization and application of biostimulants on chlorophyll levels, growth variables and production components of the cowpea cultivar, BRS Aracê. The research was conducted in the Agriculture sector of the Center for Human, Social and Agrarian Sciences of the Federal University of Paraíba. The experimental design used was randomized blocks, with 8 treatments and 3 replications. The treatments consisted of a control (T1), chemical fertilization based on the crop recommendation (T2), G-Active biostimulant (T3), G Active biostimulant + chemical fertilization (T4), Booster biostimulant (T5), Booster biostimulant + chemical fertilization (T6), Humi[K] biostimulant (T7) and Humi[K] biostimulant + fertilization (T8). The data were subjected to analysis of variance and the means compared by Duncan's test at 5% probability. For the data on leaf nutrient contents, a grouping and principal components analysis (PCA) was performed using the R statistical package. The production components number of pods per plant, 100-grain weight and productivity were influenced by the treatments. The highest productivity was obtained in treatment 8, composed of the Humi[K] biostimulant + fertilization, with 446 kg ha-¹. For the foliar macronutrient contents, there was dissimilarity between treatments, with macronutrients contributing 82% of the accumulated variance, with a high correlation between Ca and Mg in relation to the treatments. There was synergy between N, P, K and S, and a high relationship between N and the G-Active treatment. For the foliar micronutrient contents, the accumulated variance was 66.7%, with synergy between Cu, Zn and Mo; Fe and Mn, and antagonism between Mo and B. The GActive, Booster + fertilization and Humi[K] + fertilization treatments did not present good relationships with the micronutrients in the PCA. Fertilization and the use of biostimulants did not provide significant increases in the stem diameter, dry mass of the aerial part and root of the cowpea cultivar BRS Aracê.