Effect of plant population and nitrogen rate on grain sorhum yields. (S08-stevens471137-poster)
Authors:
W.E. Stevens* - Univ. of Missouri-Delta Center P.A. Sheckell - Univ. of Missouri-Delta Center H. Wilson - Univ. of Missouri-Delta Center D.J. Dunn - Univ. of Missouri-Delta Center
Abstract:
Two field experiments were conducted to evaluate grain sorghum yield response to nitrogen fertilizer rates at different plant populations. In the first experiment, plots were evenly hand thinned to low and high plant populations (86,500 and 260,000 plants/ha). In plots receiving 0 or 56 kg N/ha at planting, grain sorghum yields were 670 to 1000 kg/ha higher in the high population treatments than the low population treatments. When N rates were increased to 112 kg N/ ha, grain sorghum plants in plots with low plant populations compensated by increasing numbers of tillers and producing larger grain heads. Yields were not significantly different between low and high populations at 112, 168, and 224 kg N/ha rates. In the second experiment, grain sorghum plots were unevenly thinned leaving 1, 2, and 3 m skips in the rows. In plots with long skips the plants were unable to completely compensate for low plant populations regardless on N rate applied. The lowest yields occurred in plots with three 3 m skips per 15 m of row.
Speaker Information: William Stevens, Univ. of Missouri-Delta Center, University of Missouri-Delta Center P.O. Box 160, Portageville, MO 63873; Phone: 573-379-5431; E-mail: [email protected]
Session Information: Wednesday, November 5, 2003, 10:00 AM-12:00 PM Presentation Start: 10:00 AM (Poster Board Number: 1114)
