About Us | Help Videos | Contact Us | Subscriptions
 

Members of ASA, CSSA, and SSSA: Due to system upgrades, your subscriptions in the digital library will be unavailable from May 15th to May 22nd. We apologize for any inconvenience this may cause, and thank you for your patience. If you have any questions, please call our membership department at 608-273-8080.

 

Institutional Subscribers: Institutional subscription access will not be interrupted for existing subscribers who have access via IP authentication, though new subscriptions or changes will not be available during the upgrade period. For questions, please email us at: queries@dl.sciencesocieties.org or call Danielle Lynch: 608-268-4976.

Abstract

 

This article in AJ

  1. Vol. 99 No. 3, p. 665-672
     
    Received: Mar 28, 2006


    * Corresponding author(s): rlbaumhardt@cprl.ars.usda.gov
 View
 Download
 Alerts
 Permissions
Request Permissions
 Share

doi:10.2134/agronj2006.0092

Sorghum Management Practices Suited to Varying Irrigation Strategies

  1. R. L. Baumhardt *a,
  2. J. A. Tolka,
  3. T. A. Howella and
  4. W. D. Rosenthalb
  1. a USDA-ARS, Conservation and Production Res. Lab., P.O. Drawer 10, Bushland, TX 79012-0010
    b Texas Agric. Exp. Stn., Blackland Res. Ctr., 720 E. Blackland Rd., Temple, TX 76502

Abstract

Increasing pumping costs and declining well capacities in regions like the Southern High Plains of Texas are requiring producers to adapt cropping practices for use with irrigation levels that vary between complete replacement of crop evapotranspiration (ET) to none (i.e., dryland production). Grain sorghum [Sorghum bicolor (L.) Moench] is a crop suited to both dryland and various deficit irrigation production systems. Our objectives were to (i) identify cultural practices (planting date, population, and cultivar maturity) that maximize sorghum grain yield for widely varying irrigation strategies; and (ii) consider effective means to allocate available water among irrigation strategies that maximizes the ratio of yield to ET, that is, water use efficiency (WUE). Using the model SORKAM and long-term (1958–1999) weather records from Bushland, TX, we simulated sorghum grain yields on a Pullman soil (fine, mixed, superactive, thermic Torrertic Paleustoll) under dryland (rain) and three deficit irrigation levels (rain + irrigation = 2.5, 3.75, or 5.0 mm d−1) for all combinations of planting date (mid-May, 15 May; early June, 5 June; and late June, 25 June), cultivar maturity (early, 95 d; medium, 105 d; late, 120 d), and plant density (12 and 16 plants m−2). For 2.5 mm d−1 irrigation level, simulated grain yields were maximized with either early or medium-maturing cultivars planted in early June. In contrast, simulated sorghum yield and WUE increased with a mid-May planting date and later-maturing cultivars for irrigation levels of 3.75 and 5.0 mm d−1 We conclude that spreading water to uniformly irrigate a field with 2.5 mm d−1 produces ∼16% less grain than concentrating the same water resources to variably irrigate a field at 3.75 or 5.0 mm d−1 with complementary (2:1 and 1:1) dryland areas.

  Please view the pdf by using the Full Text (PDF) link under 'View' to the left.

Copyright © 2007. American Society of AgronomyAmerican Society of Agronomy