About Us | Help Videos | Contact Us | Subscriptions

Soil Science Society of America Journal Abstract -

Subsoiling for Sunflower Production in the Southeast Coastal Plains


This article in SSSAJ

  1. Vol. 54 No. 4, p. 1107-1112
    Received: May 18, 1989

    * Corresponding author(s):
Request Permissions

  1. R. E. Sojka ,
  2. W. J. Busscher,
  3. D. T. Gooden and
  4. W. H. Morrison
  1. USDA-ARS Soil and Water Management Research Unit, 3793 N. 3600 E. Kimberly, ID 83341
    USDA-ARS, Coastal Plains Soil and Water Conservation Research Center, P.O. Box 3039, Florence, SC 29502
    Clemson Univ., Pee Dee Research and Extension Center, P.O. Box 271, Florence, SC 29503
    USDA-ARS, R.B. Russell Agricultural Research Center, Athens, GA 30613



Crops grown on the Paleudult soils of the South Atlantic Coastal Plain often benefit from disruption of root-restrictive subsoil layers. In this physiographic area, the response of sunflower (Helianthus annuus L.) to subsoiling was unknown. We hypothesized that in-row subsoiling would benefit sunflower performance, and that plant performance could be related to profile penetration-resistance patterns. Sunflower was grown on Norfolk loamy sand in Florence, SC, and on Orangeburg loamy sand (both fine-loamy, siliceous, thermic Typic Paleudults) in Blackville, SC, in 1985 and in Blackville only in 1987. Plots were either subsoiled using 0.45-m shanks or not subsoiled. Distribution (and, in most instances, magnitude) of cone indices were significantly different for subsoiled and nonsubsoiled profiles. Accumulation frequency of low cone indices was greater for Florence and Blackville in 1985 but not for Blackville in 1987. For subsoiled treatments, lower cone indices below planted rows persisted to late summer in 1985 at both locations, which favored plant growth. Reduction of soil profile strength produced increased seed yield, oil concentration, oil yield, and seed size in these cases. In 1987, accumulation frequency of soil strength was similar for non-subsoiled and subsoiled plots shortly after tillage. In this case, plant parameters were not statistically improved with subsoiling. No tillage × N-rate, hybrid × tillage, or hybrid × N-rate interactions were observed. If low-cone-index isopleths persist throughout the season, then a positive response to subsoiling can be expected.

A joint contribution of the USDA-ARS and the South Carolina Agric. Exp. Stn., Clemson Univ., Clemson, SC 29631.

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

Copyright © . Soil Science Society of America