650-10 Foliar Nitrogen Uptake Efficiency of Creeping Bentgrass as Influenced by Spray Volume, Adjuvants, Tank-mixing, and Fertilizer Formulation.

Poster Number 407

See more from this Division: C05 Turfgrass Science
See more from this Session: Turf and Weed Management (Posters)

Tuesday, 7 October 2008
George R. Brown Convention Center, Exhibit Hall E

Bruce Branham1, Richard Mulvaney1 and Shelby W. Henning2, (1)Natural Resources and Environmental Sciences, University of Illinois, Urbana, IL
(2)Natural Resources and Environmental Sciences, Univ. of Illinois, Urbana, IL
Abstract:
Nitrogen is often foliarly applied to highly managed turfgrass swards but methods to enhance N-uptake efficiency are not well characterized. This study was conducted to determine the factors that control N-uptake efficiency by the foliage of creeping bentgrass [(Agrostis stolonifera L.)] with a goal of maximizing foliar N uptake. The effects of spray volume, adjuvants, tank-mixing, and fertilizer formulation were investigated using 15N labeled urea or ammonium sulfate at Urbana, IL on a Drummer silt loam (fine-silty, mixed, mesic Typic Endoaquoll). Nitrogen uptake was monitored by sampling foliage over a 24-hour period for total Kjeldahl nitrogen (TKN) and 15N enrichment by mass spectroscopy. Ammonium sulfate was taken up as effectively as urea, but caused unacceptable turf injury during warm (>20 C) weather. Most nitrogen applied to the foliage in ammonium form was absorbed by the plant within 4-6 hours. Uptake efficiency was greatly reduced during periods of hot (>30C) weather. Also, there was daily flux of nitrogen in the leaves of turf, indicating there may be rapid transport of the nutrient throughout the plant during the day.

See more from this Division: C05 Turfgrass Science
See more from this Session: Turf and Weed Management (Posters)