The genomes of the UNTWIST core collection (54 camelina lines), comprising commercial cultivars, landraces, and breeding lines, were sequenced demonstrating that it represents the genetic diversity of camelina. Controlled glass house experiments assessed the impact of drought and heat at an early stage in development, establishing the divergent response of the different genotypes to environmental stress. Plant growth and physiological responses and antioxidant capacities varied within the different lines. Moreover, untargeted and targeted metabolic profiling identified specific stress-responsive metabolomes that differed across the core collection. This combinatorial phenotyping approach identified different adaptive responses with substantial variation in line-specific responses to each of the applied stresses, indicating juvenile camelina lines have significant plasticity and access different stress response strategies.
To characterize the performance of the camelina core collection lines under diverse environmental field conditions, trials were performed with a fall sowing in Spain and Italy and a spring sowing in France and the UK. Yield parameters and seed oil content and composition demonstrated the plasticity of camelina to adapt to different climates and, in line with the results of the glass house trial, the diversity within the core collection. The combined agronomical and physiological data from field and glass house trials, together with the genome sequencing data are used to develop machine-learning models. The top-down models can so far predict flowering time, plant height, certain fatty acids in the seeds and thousand grain weight.
For the systems-based analysis of camelina´s plasticity to challenging environmental conditions, four focus lines have been selected from the core collection for their high diversity and their behaviour in open fields and in glasshouse trials. The genomes of the focus lines were sequenced with long-read technology to assemble very high-quality reference genomes, and the new genomes were used for structural and functional gene annotation. Focus lines are further evaluated in the field under diverse environmental conditions, with cropping systems adapted to the respective conditions in France, Italy, Spain, and the UK. Heat and drought stress experiments at the flowering stage provided a complete phenotypic evaluation of their performance under stress condition. Detailed multi-omics analyses of the camelina focus lines identified the plasticity of the adaptive response of leaves, seeds, and capsules on the transcriptional, metabolic, lipid, redox-status and enzyme activity level to drought and heat.
Concomitant with the molecular discovery studies, multi-year field trials to optimise the agronomic management of camelina in different geographical environments were performed. Optimised agronomic management protocols have been developed for camelina as a cover crop for marginal land in Spain, as an autumn crop for double cropping in Italy, as a spring crop in the UK and as summer catch crop in France.
To make the results accessible and publicly available towards the end of the project, a web-based Knowledge Hub (Plant Adaptation Hub) with the data from UNTWIST is developed. Publicly available data is also integrated and cross linked. Interactive visualization of phenotypic data is continuously extended and tools for genome wide association analysis (GWAS) and multidimensional scaling (MDS) analysis for enhanced data exploration have been integrated into the Hub.
