HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kebede, H. Articles by Ferris, D. M. Search for Related Content PubMed Articles by Kebede, H. Articles by Ferris, D. M. Agricola Articles by Kebede, H. Articles by Ferris, D. M.

Physiological and Anatomical Features of Two Triticum dicoccoides Wheat Accessions Differing in Photosynthetic Rate

Dep. of Agronomy, Oklahoma State Univ., Stillwater, OK 74078
USDA-ARS, Plant Introduction Stn., Washington State Univ., Pullman, WA 99164

Brett F. Carver^* and David M. Ferris

Dep. of Agronomy, Oklahoma State Univ., Stillwater, OK 74078

^* Corresponding author.

The wild tetraploid species Triticum dicoccoides (L.) Korn has many traits that may be useful to hexaploid wheat (T. aestivum L.). Two accessions of this species (PI 428042 and PI 428109) were found have similar-sized leaves, but they differ by 30% in net CO₂ assimilation per unit leaf area (A). We sought to identify physiological and anatomical factors that would explain the difference in photosynthetic rate between the two accessions, and between these accessions and the hexaploid wheat ‘TAM W-101’. Photosynthetic responses to CO₂ (at 20 and 210 mL O₂ L^–1 air), light, and humidity, and also ribulose bisphosphate carboxylase (rubisco) activity and sucrose concentration, were determined on new fully expanded leaves of each genotype. Anatomical features associated with photosynthesis were determined using light and electron microscopy. PI 428109 showed consistently higher A than PI 428042 at varying levels of CO₂, light, and humidity. Higher rubisco activity was observed in leaves of PI 428109 than PI 428042, as also indicated by a greater slope of the initial linear portion of the A vs. c_i (intercellular leaf CO₂ concentration) curve. A higher sucrose concentration was observed in the leaves of PI 428042 than in PI 428109. No anatomical differences were detected between the two T. dicoccoides accessions. Therefore, photosynthetic differences between the two T. dicoccoides accessions were biochemically, and not anatomically, driven.

Received for publication January 17, 1991.