Peanut Irrigation Study, 1989, Georgia Coastal Plain

Yield Comparisons:
Study:

Research Objectives:

    1. Determine root growth rates of peanut before, during, and after each of three 30-day drought periods as compared with non-stressed peanut. To confirm 1988 rhizotron study.
    2. Compare irrigation scheduling techniques for their ability to meet peanut water needs - yield effects and water use efficiency.
    3. Compare model predictions of soil water and peanut biomass components with measured soil water and biomass.
    4. Compare changes in pod zone moisture and temperature during dewatering of the root zone.
    5. Determine the effect of water stress on the occurrence and distribution of peanut root hairs.
    6. Examine limb-rot incidence as affected by water regimes in the absense of wheel traffic.
    7. To quantify water infiltration and redistibution rates as affected by antecedent moisture.
Treatments:
 1.Well-watered - irrigate whenever tensiometers at three adjacent depths indicate soil water pressure (SWP) falls below -30 cb for one half of the replicates; add 3.1 cm
 2.Control - Shallow - irrigate whenever tensiometers at the 20 and 30 cm depths indicate an average SWP below -40 cb for one half of the replicates; add 2 cm. Ignore deeper SWC.
 3.Deep - irrigate whenever tensiometers at the 60, 75, and 90 cm depths indicate an average SWP below -40 cb for one half of the replicates; add 5 cm. Ignore shallow SWC.
 4.20-50 day drought - except during this 30 day period irrigate as well watered. Refill the entire profile at the end of the drought period.
 5.50-80 day drought - except during this 30 day period irrigate as well watered. Refill the entire profile at the end of the drought period.
 6.80-110 day drought - except during this 30 day period irrigate as well watered. Refill the entire profile at the end of the drought period.
 7.Fixed - Irrigate twice with 5 cm water, once at 60 dap, once at 76 dap, adjusted later if SWC is greater than 50% full due to rain.
 8.No irrigation

Basic Crop Management: PLANTED - 08 May 1989 (placed 5 cm deep); HARVEST - 18-20 Sep 1989; 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:
 Tensiometer at 30 cb - well-watered 20-90 cm depths
 Treatment 2:
 Control - Tensiometer at 40 cb - shallow, 20-30 cm depths
Treatment 3:
 Tensiometer at 40 cb - deep, 60-90cm depths
Treatment 4:
 20-50 dap drought period
 Treatment 5:
 50-80 dap drought period
 Treatment 6:
 80-110 dap drought period
 Treatment 7:
 Fixed - 60 dap and 76 dap
 Treatment 8:
 No irrigation
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.