About Us | Help Videos | Contact Us | Subscriptions



This article in CS

  1. Vol. 39 No. 4, p. 1101-1106
    Received: Aug 13, 1998

    * Corresponding author(s): franka@mandan.ars.usda.gov
Request Permissions


Soil Water Use by Diploid and Tetraploid Russian Wildrye

  1. A. B. Frank  and
  2. J. D. Berdahl
  1. USDA-ARS, Northern Great Plains Research Laboratory, P.O. Box 459, Mandan, ND 58554.



Russian wildrye [Psathyrostachys juncea (Fisch.) Nevski] is an important cool-season forage grass for the Northern Great Plains, but it exhibits poor seedling vigor. Tetraploid (2n=4x=28) plants have improved seedling vigor over diploid (2n=2x=14) plants, but data is lacking on plant-soil-water relations. Objectives of this research were to compare water-use efficiency (WUE), evapotranspiration (ET), roofing activity, and water extraction in relation to Haun stage for diploid and tetraploid Russian wildrye. A diploid and tetraploid entry were evaluated for 3 yr under two water treatments (50 and 150% of monthly average precipitation for 1 April to 1 November) and two fertilizer rates (10 and 134 kg N ha−1) in a rain shelter. The soil was a Parshall fine sandy loam (Coarse-loamy, mixed, superactive, frigid Pachic Haplustoll). Cumulative ET averaged across the 50 and 150% water treatments was 138 and 141 mm for the diploid and tetraploid, respectively. Rate of root activity progression was linear with Haun to the 1.2-m depth and ranged from 0.148 to 0.163 m per Haun stage for the diploid and tetraploid, respectively, at 50% water. Forage yield of the tetraploid was greater than the diploid at the 50%, but not at the 150% water treatment. Water-use efficiency was higher for the tetraploid (3.8 g kg−1) than the diploid (3.1 g kg−1) at the 50% water treatment, but at 150% water the entries were not different. Overall, the tetraploid entry exhibited a more favorable WUE and other soil water relations than did the diploid entry.

USDAARS, Northern Plains Area, is an equal opportunity/affirmative action employer and all agency services are available without discrimination.

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

Copyright © .