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

This Article Figures Only Full Text Free Full Text (PDF) Free 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 HighWire Citing Articles via Google Scholar Google Scholar Articles by Ziska, L. H. Articles by Blumenthal, D. M. Search for Related Content PubMed Articles by Ziska, L. H. Articles by Blumenthal, D. M. Agricola Articles by Ziska, L. H. Articles by Blumenthal, D. M. Related Collections Global Change Oat

CROP ECOLOGY, MANAGEMENT & QUALITY

Empirical Selection of Cultivated Oat in Response to Rising Atmospheric Carbon Dioxide

^a USDA-ARS, Alternate Crop and Systems Lab., Beltsville, MD 20705
^b USDA-ARS, Rangeland Resource Research Unit, Cheyenne, WY 82001

^* Corresponding author (l.ziska{at}ars.usda.gov).

Carbon dioxide is a principle resource for plant growth; as such, the ongoing increase in its concentration may allow breeders to begin selecting for optimal cultivars among current crop lines. Such a program may not be necessary, however, if breeders have, by empirical selection, already chosen the most responsive cultivars. To test this hypothesis, we examined the growth and vegetative characteristics of individual plants of cultivated oat (Avena sativa L.) from seven geographical locations to CO₂ concentration ([CO₂]) increases that corresponded roughly to the [CO₂] from the 1920s, the current [CO₂], and the [CO₂] projected for the middle of this century (300, 400, and 500 µmol mol^–1, respectively). In contrast to our predictions, newer lines were less responsive than older lines to rising [CO₂] in terms of both leaf area and tiller number. A comparison of phenotypic variability indicated that for almost all measured parameters, older lines had a greater degree of intraspecific variability (i.e., newer lines were more uniform). As a consequence, a number of CO₂-sensitive lines among older cultivars were identified with respect to parameters such as vegetative biomass or tiller production. Our results suggest that for oat: (i) newer lines are not intrinsically more responsive to rising CO₂ levels than older lines; and (ii) phenotypic homogenization among modern lines could hamper efforts to identify desirable characteristics associated with CO₂ responsiveness.

Abbreviations: PAR, photosynthetically active radiation

This article has been cited by other articles:

				H. Shimono, M. Okada, Y. Yamakawa, H. Nakamura, K. Kobayashi, and T. Hasegawa Genotypic variation in rice yield enhancement by elevated CO2 relates to growth before heading, and not to maturity group J. Exp. Bot., February 1, 2009; 60(2): 523 - 532. [Abstract] [Full Text] [PDF]