Molybdenum Response of Alfalfa on Indiana Soils in the Greenhouse

Abstract

AbstractGreenhouse experiments were conducted to determine the response of alfalfa to Mo on Indiana soils.Twenty‐five soils, representing 18 soil types from the major soil areas of Indiana, were used. The pH of the soils ranged from 4.8 to 7.4. Treatments included combinations of no lime; 250 pounds of CaCO3 per acre, mixed with the surface inch of soil; limed according to soil test; no Mo; and 2 pounds of Mo per acre. Three cuttings of alfalfa were obtained.Mo produced significant yield increases on 9 of the 18 soil types studied, and 7 others gave responses approaching significance. A significant response to Mo was obtained at the high rate of lime on 2 soils, and on 6 other soils increases were obtained which approached significance. This suggests a deficiency of total Mo in these soils. Mo treatment reduced alfalfa yields on 3 of the acid soils which received the high rate of lime and on I soil having an initial pH of 7.0.Results with one soil indicated that drying prior to cropping increased the response to Mo.