Effects of foliar application of boron doses on peanuts

Abstract

Boron (B) is the most limiting micronutrient for peanut production in Brazil. The foliar fertilization can be a viable strategy for the supply of this nutrient to the culture. The aim of this study was to evaluate the production components of the peanut crop as a function of different rates of B via leaf. The experimental design used was in randomized blocks, with 4 replications. The treatments consisted of the application of B (0, 250, 500, 750, 1,000, 1,250 and 1,500 g ha^-1 of B), applied via leaf at 30, 45 and 60 days after the emergence of the culture. The plots were 3.6 meters wide, with 4 planting lines spaced 0.90 m apart (2 central lines as a useful plot), 20 meters long and an average stand of 12 plants per meter. The cultivar used was IAC OL 4. Leaf B content and pod yield were evaluated. Leaf applications of B doses, between 250 to 1,500 g ha^-1, increase the levels of B in the leaves. However, applications of B do not influence the yield of peanut pods even in soil with low B content (<0.12 mg dm^-3). It concludes that further studies are recommended to understand the effect of the fertilization on the peanut production components. Updates are necessary in the sufficiency indexes of B in the soil and in the plant for the crop.