Responses of barley genotypes to elevated CO2

Background and Objective

The continuing increase in atmospheric CO₂ concentration will have direct implications for plant growth and agricultural ecosystems, as CO₂ is the important resource for plant growth. Plant growth and yield of C3 crops are known to be positively affected by elevated CO₂. Although recent evidence from studies with a small number of genotypes suggest that intraspecific variability exists among genotypes, a systematic evaluation of a broader set of diverse genotypes under field conditions is still lacking. However, sufficient genetic variation is a prerequisite that would allow breeders to select for CO₂ responsiveness. Here, we study the responses of a large number of diverse barley genotypes to elevated CO₂ in order to identify genotypes that are able to utilize elevated CO₂ concentration most effectively.

Approach

To get information about the genetic variability in winter barley 100 barley genotypes are grown in open-top field chambers in three consecutive growing seasons and exposed to different CO₂ levels. Plants are phenotyped for growth and yield parameters as well as for physiological and morphological traits. Whole genome association analyses are performed based on the phenotypic data.

Results

First results showed significant differences between the genotypes in their response to elevated CO2 for all yield and growth parameters, however,  CO2 effect was mor pronounced in 6-rowed compared to 2-rowed genotypes.