|
|
||||||||
Two hard red spring wheat (Triticum aestivum L.) genotypes, the commercial variety Era and an experimental genotype 8037, selected for this work because it had unusually large heads, were grown in normal air and in atmospheres enriched in CO2 to 600 ppm by volume in the field and in growth chambers in two day/night temperature regimes of 25/20 and 13/17 C. The growth period was divided into three stages: a) the vegetative period from germination to floral initiation; b) the floral development stage from floral initiation until anthesis; and c) the grain development stage from anthesis until maturity. Normal or CO2 enriched air was applied during each of these developmental stages in all possible combinations giving eight treatments in each experiment.
Both genotypes showed an increase in grain yield in the field and in the 25/20 C temperature regime in growth chambers when CO2 enrichment was applied during stage b or c or both. No effect of CO3 enrichment on grain yield was observed when the enrichment was applied before stage b in any experiment or at any development stage in the 13/17 C temperature regime. For both genotypes in the field and in the 25/20 temperature regime, CO2 enrichment caused an increase in kernel number/plant when applied during stage b, and in kernel size when applied during stage c. This suggests that kernel number and size are both dependent on the supply of photosynthate. Thus, we conclude that a screening procedure, that is effective in classifying genotypes as to their photosynthetic capacity during either stages b or c, might be useful in identifying desirable parental lines for a yield-oriented wheat breeding program.
Key Words: Floral development Photosynthetic capacity Triticum aestivum L.
2 Former graduate research assistant (presently assistant professor, Department of Crop Science, North Carolina State University, Raleigh, NC 27607) and professor, respectively.
Received for publication May 28, 1974.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Vadose Zone Journal | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||