Influência do boro via aplicação foliar em soja na várzea irrigada no Tocantins

Abstract

Soybean cultivation (Glycine max (L.) Merrill) is one of the main commodities of world agribusiness. Brazil has been configured in this scenario as one of the largest producers of this oilseed, standing out with high yields. The irrigated várzea is an area of extreme economic and social importance for the southern state of Tocantins, generating income and jobs throughout the year. Foliar fertilization is used to supplement or complement nutrient levels in the plant, so that it can perform all its metabolic processes normally. Boron is an essential element in all phases of the soybean cycle, participating in several physiological processes. The objective of this work was to verify the influence of foliar fertilization, applied at three stages of soybean cultivation in the reproductive period, with increasing doses of boron sources, about the components of yield, yield and germination of soybean seeds. The work was carried out under lowland conditions, in the municipality of Formoso do Araguaia - TO, between the harvest of the agricultural year of 2016. The experimental design was a randomized complete block design in 2x3x5 triple factorial (products x seasons x doses) with four replications. The characteristics evaluated were: number of pods per plant (NVP), number of seeds per plant (NSP), mass hundred seeds (MCS), productivity (PROD), Percentage of germination (G%) and emergence speed index (EVI). It was verified that the treatments in which there was application of the source of boron, composed of boric acid and octaborate, obtained the best answers for all characteristics evaluated. In the soil and climatic conditions of irrigated lowland harvest, applications of B in R2 and R4 obtained the best response. Higher averages were obtained with the application of 1,5 to 2 kg. ha-1 of boron.