About Us | Help Videos | Contact Us | Subscriptions



This article in CS

  1. Vol. 29 No. 5, p. 1232-1239
    Received: May 23, 1988

    * Corresponding author(s):


Analysis of Nitrogen Accumulation and Use in Bread and Durum Wheat

  1. Kanwarpal S. Dhugga  and
  2. J. G. Waines
  1. D ep. of Biological Sciences, Stanford Univ., Stanford, CA 94305
    D ep. of Botany and Plant Sciences, Univ. of California, Riverside, CA 92521



Since a significant portion of applied soil N is lost by leaching and denitrification, it is desirable to breed crop cultivars with improved N use efficiency. This study was undertaken to determine the influence of soil N supply on genotypic variation for preanthesis and postanthesis shoot N accumulation, the effect of preanthesis N and grain N yield on postanthesis N accumulation, and N use efficiency. A set of 12 bread (Triticum aestivum L.) and two durum (T. turgidum L. var durum Desf.) wheat genotypes was studied over three planting dates in 2 yr with three N levels within each planting date on a Ramona type A sandy loam (coarse fine-loamy, mixed thermic Typic Haploxeralf). Differences among genotypes for shoot N accumulation before and after anthesis became obvious at the highest soil N level. At this level, some genotypes either stopped accumulating or showed a net loss of shoot N between anthesis and maturity, which appeared to be associated with superior preanthesis N accumulation capacity and reduced grain N yield of such genotypes. Uptake efficiency (total shoot N/soil N supply) became slightly more important than utilization efficiency (grain yield/total shoot N) in determining N use efficiency (grain yield/soil N supply) with increasing soil N supply. Nitrogen harvest index (grain N yield/total shoot N) fully explained the reduced contribution of utilization efficiency at higher soil N levels. We suggest that bread wheat genotypes G4843 and ‘Anza’ should be crossed in an attempt to recombine the superior N accumulation capacity of the former with the superior grain yield of the latter to develop a cultivar with improved N use efficiency.

Research supported by the California Agric. Exp. Stn. and the Univ. of California, Riverside, Botanic Gardens.

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

Copyright © .