Liming increases alfalfa yield and crude protein content in an acidic silty loam soil

Abstract

A three year field trial examined the effect of three hydrated lime (HL, Ca(OH)₂) rates (0, 1.5 and 3 Mg HL ha^-1) on yield and quality characteristics of alfalfa on an acid soil (pH_{water 1:2.5} 4.7) in Western Serbia. Lime was applied only once. Total dry mass yields of a new planting alfalfa (Medicago sativa L.) increased up to 6500% by the treatments of HL, compared with the untreated control. Lime application significantly (P ≤ 0.05) increased the crude protein content of alfalfa, in comparison to the no limed control. Liming also significantly increased Ca, K, and P concentrations but decreased Mg, Fe, Mn, Zn, and Al concentrations in alfalfa tissue, compared with the control treatment. Alfalfa yield increase was attributed to the increase of Ca, P and K uptake. Furthermore, the low (1.5 Mg HL ha^-1) and high (3 Mg HL ha^-1) lime treatments increased soil pH even further by 0.9 and 1.5 pH units, respectively. The results suggest that an initial application of hydrated lime at a rate of 3 Mg HL ha^-1 may ameliorate soil acidity and increase the yield and quality characteristics of alfalfa at least over a 3-year period.

Keywords: Alfalfa, soil acidity, liming, herbage yield, elemental composition