Effect of soil Ph and nitrogen source on the nutrient status in peach: II. Micronutrients

Abstract

The concentration of aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), and copper (Cu) in leaves, shoots, trunks, and roots, and the content of plant‐available Mn and Al in soil was examined after 13‐year treatments of soil pH and nitrogen (N) source in a peach orchard of North Carolina. Raising soil pH by liming tended to reduce soil Al content, but had no effect on soil Mn. Tissue Al and Mn level was decreased in high pH treatment. Poultry manure application resulted in the highest soil Mn content but the lowest soil Al. In comparison with calcium nitrate [Ca(NO₃)₂], ammonium sulfate [(NH₄)₂SO₄] increased Al availability in soil while had little effect on soil Mn. Acid‐forming N, especially (NH₄)₂SO₄, increased the concentration of tissue Al, Mn, Zn, and Fe. The plants treated with various basic N materials similarly contained lower levels of Al or Mn. Manure treatment resulted in high tissue Cu and Zn but low tissue Fe levels. Tissue Zn was low when mineral N sources containing calcium (Ca) or sodium (Na) were applied.