Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 4, 2004
Publication Date: November 4, 2004
Citation: Karlen, D.L., Jaynes, D.B., Pellack, L.S., Heikens, K.E. 2004. Soil, Wheat, and Sorghum Response to Tillage Under Rhizotron Conditions [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin. Technical Abstract: Do soils from different locations throughout the U.S. respond similarly to tilled and non-tilled management under rhizotron conditions? Soil columns measuring 30 cm by 30 cm by 100 cm were collected from Cecil scl, Miami sil, Palouse sil, and Weld sil sites in Georgia, Indiana, Washington, and Colorado and placed in the rhizotron at the National Soil Tilth Laboratory (NSTL). Four spring wheat - grain sorghum cropping cycles were imposed on four replicates of each soil with and without surface 'tillage' before planting each crop. One cycle for each crop failed to produce grain, presumably because lighting problems disrupted the phytochrome system within each crop. Average wheat grain yields for crop cycles 1, 2, and 4 were equivalent to 6.2, 6.6, 6.9, and 7.2 Mg/ha for the four soils, respectively, while sorghum yields for crop cycles 1, 3, and 4 were equivalent to 9.0, 10.1, 9.9, and 9.7 Mg/ha, respectively. Equivalent 'no-tillage' yields were significantly higher for wheat (7.2 vs 6.3 Mg/ha) but there were no differences (9.7 Mg/ha) for sorghum. Water use, changes in soil quality indicators, crop yield components, and N removal are being computed and will be discussed. We conclude the NSTL rhizotron and our experimental approach provided a good comparison among soils and based on calculated yields reasonably represented good growing conditions for both crops.