Efeito da aplicação de substâncias húmicas via foliar em parâmetros biométricos da soja (glycine max)

Abstract

Soybean cultivation has great worldwide importance in several production chains, from the production of raw material to highly profitable derivatives. Thus, it has relevance for the maintenance of the quality of life of a large part of the world population. Thus, there is a need for increases in productivity. The objective of this study was to evaluate the effect of the application of humic substance to soybean, through its biometric parameters. For this, an experiment was conducted in the field using a completely randomized block design composed of 4 blocks and 5 treatments. The treatments were: doses of humic substances of the commercial product Ativa Humic (Agricultural Alternative) in different stages, with T1 (control group), T2 1 L ha-1; T3 2 L ha-1; T4 0.5 L ha-1 and T5 1 L ha-1 all applied at vegetative stage 4 (V4), later at the reproductive stage R1 were applied in treatments T4 0.5 L ha-1 and in treatments T5 1 L ha -1 of the product. The following biometric parameters were evaluated: number of pods with 1, 2, 3 and 4 grains, pod weight, number of upper and lower leaves, stem weight, wet and dry weight, productivity in kg ha- 1, dry weight with 13% moisture content and chlorophyll content in leaves. Data were analyzed by the F test and the means of the treatments compared by the Scott Knott test at 5% probability. There was no statistical difference between treatments, except for their influence on the number of pods with 3 grains and pod weight; however, the lowest mean was 31.7; 1.12; 0.93; 2609.0; 43.4; 1.05; 15.4 and the largest were 36.7; 1.40; 1.18; 3314.7; 55.2; (kg ha-1), yield (ha-1bags), dry weight plus 13% moisture content and chlorophyll content. On the other hand, under the conditions in which the experiment was conducted, the application of humic substances via foliar was not justified, since there was no expressivity for the production and no productivity.