Maize Irrigation Study, 1982, Georgia Coastal Plain

Yield Comparisons:
Study:

Research Objectives:

    1. Determine the number of stress days added by delaying irrigation for 1, 2, and 3 days.
    2. Relate the difference in leaf temperature and ambient temperature to stress days, to visual stress symptoms and to yield reductions.
    3. Compare relative yield reductions caused by the irrigation delay.
    4. Compare the redistribution of soil water following irrigation when delayed irrigation is used.
Treatments:
 1.Control - Tensiometer - shallow (20-30 cm), 0.3bar, on time
 2.Tensiometer - shallow (20-30 cm), 0.3bar, one day delay
 3.Tensiometer - shallow (20-30 cm), 0.3bar, two day delay
 4.Tensiometer - shallow (20-30 cm), 0.3bar, three day delay

Basic Crop Management: PLANTED - 10 Mar 1982 (rows 0.9m apart); HARVEST - 21 Jul 1982 (2-row grain combine); TILLAGE - Moldboard Plow (30 cm deep plus smoothing and bed shaping), wheel traffic controlled at 1.2 m centers; FERTILIZATION - Typical Extension Recommended Rate; WEED & PEST CONTROL: Typical Extension Recommendations.
Chronological Treatment and Observation Details

Observations and data sets for individual treatments (crop years) follow:
Treatment 1:
 Control - Tensiometer - shallow (20-30 cm), 0.3bar, on time
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 18 Mar 1982; Pollination (R2) - 31 May 1982; Maturity (Black layer) - 06 Jul 1982
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 12.49; Individual plots - 11.98, 13.56, 12.67, 11.76 Text File
Treatment 2:
 Tensiometer - shallow (20-30 cm), 0.3bar, one day delay
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 18 Mar 1982; Pollination (R2) - 31 May 1982; Maturity (Black layer) - 06 Jul 1982
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 11.88; Individual plots - 11.82, 11.63, 11.34, 12.71 Text File
Treatment 3:
 Tensiometer - shallow (20-30 cm), 0.3bar, two day delay
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 18 Mar 1982; Pollination (R2) - 31 May 1982; Maturity (Black layer) - 06 Jul 1982
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 12.96; Individual plots - 13.30, 12.24, 13.55, 12.74 Text File
Treatment 4:
 Tensiometer - shallow (20-30 cm), 0.3bar, three day delay
  • Irrigation Dates and Amounts: Text Format;
  • Phenology: Emergence - 18 Mar 1982; Pollination (R2) - 31 May 1982; Maturity (Black layer) - 06 Jul 1982
  • Stand Count:
  • Soil Water Pressure Observations: Tensiometer & Gypsum Block
  • Yield Corn Grain, 15.5% moisture, T/ha: Average - 11.81; Individual plots - 12.99, 11.03, 11.47, 11.71 Text File
For more information on the study and its interpretation contact:
Dr. Jim Hook Professor, Soil and Water Management
Crop and Soil Sciences Department and NESPAL
The University of Georgia, College of Agricultural and Environmental Sciences
P.O. Box 748, Tifton, GA 31793-0748
e-mail: jimhook@tifton.cpes.peachnet.edu

Page developed by James E. Hook, Amanda Richards, and Linsey Forlow.
Last Modified on 29 June 2000.