Effect of N-form on macronutrient and micronutrient concentration and uptake of creeping bentgrass

Nitrogen-form effect on nutrient uptake and the subsequent concentration of nutrients in turfgrass plant tissue has not been thoroughly investigated. This study evaluated the effects of clipping regime and N-form on the tissue concentration of macronutrients and micronutrients and macronutrient uptake in 'Penncross' creeping bentgrass (Agrostis palustris Huds.). Turfgrass plugs were grown under greenhouse conditions in a modified Hoagland's solution with a combination of three nutrient solutions (100% NO3(-), 100% NH4(+), and 50:50 ratio of NH4(+):NO3(-)) and two cutting regimes (cut and uncut). Concentrations of macronutrients and micronutrients were determined for shoot, root and verdure. Nutrient uptake was determined weekly. Uncut NO3(-)-treated plants accumulated higher concentrations of K, Ca, Mg, B and Cu in the shoot tissue; P, K, Ca, Mg, B, Cu, Mn and Zn in the root tissue; and P, Ca, Mg, B, Fe and Mn in the verdure compared to uncut NH4(+)-treated plants. Nitrate uptake was greater with uncut NO3(-)-treated plants than was NH4(+) absorption with uncut NH4(+)-treated plants. Plants grown with the uncut 50:50 treatment adsorbed more NH4(+) than NO3(-). Plants grown with the uncut NO3(-) and 50:50 treatments adsorbed higher amounts of P, K, and Ca compared to the NH(+) treatment. The cut NO3(-)-treated plants accumulated higher concentrations of K in the shoot tissue; P, Ca, Mg, B, Cu, Fe and Mn in the root tissue; and B in the verdure than did the cut NH4(+)-treated plants. Cut NO3(-)-treated Plants adsorbed less NO3(-) than did cut NH4(+)-treated plants adsorbed NH4(+). The cut 50:50 treatment adsorbed more NH4(+) than NO3(-). Plants grown with NO3(-) and 50:50 treatments, under both cutting regimes, resulted in higher concentrations of most macro- and micronutrients and greater nutrient uptake compared to the NH4(+)-treated plants.