subproject G: "Innovations in plant performance: genetic analysis of biomass accumulation"
The project part G employs automated, non-destructive phenotyping to study the temporal dynamics of vegetative biomass formation in winter wheat up to the onset of flowering under controlled greenhouse conditions. The collection is daily imaged for vegetative biomass growth in well-watered and in seasonal spring drought conditions (Fig. 1), that occur more frequently in Germany due to the ongoing climate change. By our deep screening of vegetative growth related parameters we complement the agronomic traits obtained at maturity in the field by the other partners. Moreover, also half of all greenhouse experiments went to maturity to evaluate how well a higher vegetative biomass as photosynthetic source tissue can be transferred into grain yield and how strongly final yield is diminished by a seasonal drought event. In our setup a drought period is followed by a recovery phase and we are able to classify genotypes into drought tolerant or sensitive as well as according to their recovery ability.
We want to figure out what is the genetic architecture of biomass formation under well-watered condition in comparison to seasonal drought and see which QTL/genes play a role at what time and for how long. Additionally, we aim to investigate if older varieties may still harbor important alleles that might have been lost in the breeding process and should be re-introduced to ensure yield stability in wheat.The answers to all this questions will be revealed by combination of the collected phenotypic traits with genetic information in form of a genome-wide association study and by relating biomass formation with the obtained yield parameters from the field experiments. Analysis of biomass formation prior the drought period start revealed temporal dynamics of the genetic architecture within the first three weeks of growth (Fig. 2).