Detailed temporal and physiological dissection of limitations to water and nitrogen uptake efficiency

• Applicant: Professor Dr. Andreas Stahl
• Subject Area: Plant Breeding and Plant Pathology ; Plant Cultivation, Plant Nutrition, Agricultural Technology
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 518913298

Wheat is one of the most important staple food crops and high grain yields are essential for global food security. Breeding raised yields continuously over the past century, however yield potential is increasingly suppressed by challenges associated with climate change and regulatory restrictions on crop inputs. A better understanding of the genetic and physiological interplay between physiological and metabolic processes underlying source-sink activities is vital to optimise adaptive responses that limit yield potential and to account for genotype*environment*management (G*E*M) interactions. In a previous collaboration, a large panel of elite European winter wheat cultivars was extensively phenotyped in a G*E*M context. Findings from this project suggest that selection over decades resulted in an accumulation of chromosome segments with favourable effects on source- and sink-related key component traits of yield, such as water and nutrient use efficiency, biomass, radiation interception efficiency and green canopy duration. However, these putative physiological advantages did not always result in increased grain yield. This suggests that an efficient recombination of source and sink traits as component traits of yield has great potential to enhance genetic gain in a wide range of environmental and management scenarios.The aim of the subproject 2 is to analyze the interactions between water and nitrogen uptake on the one hand and their temporal distribution along the growing season on the other. For this purpose, the water uptake is recorded in ultra-high resolution by using two complementary phenotyping platforms (DroughtSpotter XXL and Plantarray). This allows to track transpiration patterns not only over the whole growing season, but also within every single day and to relate them to other phenoytypical traits. In parallel, multi-site field experiments with contrasting water and nitrogen supply will be conducted and multispectral reflectance measurements will be used to record growth dynamics at high resolution. The joint data analysis should lead to the determination of wheat trait profiles that allow the smallest trade off conflicts under the respective stress scenarios. In cooperation with the other subprojects, the identification of ideotypes and the determination of genetic determinants represent the final project goal.

• DFG Programme: Research Grants