|Baumhardt, Roland - Louis|
Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/1/2008
Publication Date: 10/5/2008
Citation: Kapanigowda, M., Stewart, B.A., Howell, T.A., Baumhardt, R.L., Kadasrivenkata, H., Colaizzi, P.D. 2008. Clump planting to reduce the tiller production and increase the yield in dryland corn [abstract]. 2008 Joint Meeting of American Society of Agronomy, Soil Science Society of America, and Crop Science Society of America, October 5-9, 2008, Houston, Texas. Paper No. 755-3. 2008 CD ROM. Interpretive Summary:
Technical Abstract: Under dryland conditions of the Texas High Plains, grain production is limited by sparse and erratic precipitation that results in severe water stress during grain formation. When plant populations are reduced to conserve soil water for use during grain filling, tillers often form during the vegetative period and negate the expected benefit. We hypothesized that growing corn in clumps spaced 1 m apart to reduce tillers, increase mutual shading, and conserve soil water for grain filling would increase grain yield. Studies were conducted during 2006 and 2007 at Bushland, TX with two planting geometries (clump vs. equidistant), two irrigation methods [LEPA (Low Energy Precision Application) vs. LESA (Low Elevation Spray Application)] at three rates (dryland, 75 mm and 125 mm in 2006; and dryland, 50 mm and 100 mm in 2007). For dryland plots in 2007, clump plants had only 0. 17 tillers per plant (6630 tillers ha**-1 compared to 1.56 tillers per plant (60,840 tillers ha**-1 for equidistant plants. Tillers accounted for 13% of the stover for the equidistant plants, but less than 1% of the grain. Clump planting produced significantly higher grain yields (2657 vs. 2240 kg ha**-1 and 3495 vs. 3129 kg ha-during 2006 and 2007, respectively) and harvest indexes (0.54 vs 0.49 and 0.52 vs. 0.39 during 2006 and 2007, respectively) compared to equidistant plants in dryland conditions. Water use efficiency was also higher for the clump treatments. In 2007, each additional mm of irrigation increased grain by 37.8 and 32.1 kg ha**-1 for clump and equidistant treatments, respectively. There was no yield difference for method of irrigation. Growing plants in clumps compared with equidistant plants reduced the number of tillers, early vegetative growth, and LAI (Leaf Area Index) so that more water was available during the grain filling stage. This may be a useful strategy for growing corn with low plant populations in dryland areas.