Manganese foliar fertilizer does not impact yield or grade of Florida peanut

Abstract

In the southeastern United States, peanut [Arachis hypogaea (L.)] is grown in sandy soils with recommended pH ranges (6.2–6.5) that might cause manganese (Mn) deficiency. This study evaluated the effect of foliar-applied Mn on yield, grade and leaf nutrient content of peanuts grown in sandy soils with a moderately acidic pH. Treatments compared two rates, timings, and sources (1x or 2x current recommendation; one application at first flower or one application at first flower and again 2 weeks later; manganese sulfate (MnSO₄) or chelated Mn-EDTA [ethylenediaminetetraacetic acid disodium manganese]). Small plots were established at three site-years, and treatments were replicated five times using a randomized complete block design. Site-years had average pod yields of 7221–9899 kg ha⁻¹ with no treatment effect within site-year (p = 0.63). Leaf Mn content averaged 43.3–67.5 ppm at each site-year, with no treatment effect within site-year (p = 0.25). Foliar applications of MnSO₄ or Mn-EDTA to peanut are not required when symptoms of deficiency in leaf tissue are not evident and soil pH is below 6.2.