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 Barta, A. L. Articles by Hodges, H. F. Search for Related Content PubMed Articles by Barta, A. L. Articles by Hodges, H. F. Agricola Articles by Barta, A. L. Articles by Hodges, H. F.

Characterization of Photosynthesis in Cold Hardening Winter Wheat¹

Photosynthesis (net CO₂ assimilation) was measured on two winter and one spring wheat cultivars (Triticum aestivum) at three stages of cold hardening. Photosynthesis during hardening was characterized by decreasing rates of CO₂ assimilation and reduced response to light and temperature changes. The winter wheats, ‘Vermillion’ and ‘Seneca,’ had higher rates of photosynthesis at all stages of hardening than did the spring wheat, ‘Justin.’ Vermillion, the most winter hardy cultivar, had significantly higher photosynthesis than Seneca when rates were averaged over all variables. Treatment of the plants with (2-chloroethyl) trimethylammonium chloride did not produce any significant changes in any of the photosynthetic parameters studied. No significant differences in specific rates of photophosphorylation or Hill reaction were noted among the cultivars, in contrast to the varietal differences found in whole plant CO₂ assimilation rates.

Key Words: Hill reaction • Photophosphorylation • Temperature adaptation • 2-chloroethyl trimethylammonium chloride

² Formerly Graduate Fellow (now Assistant Professor, Ohio Agr. Research and Development Center, Wooster, Ohio 44691) and Associate Professor, Dept. of Agronomy, Purdue University, Lafayette, Ind. 47906.

Received for publication February 26, 1970.