Periodic Reporting for period 2 - ADAPT (Accelerated Development of multiple-stress tolerAnt PoTato)
Período documentado: 2022-01-01 hasta 2023-06-30
To obtain insights into molecular events during stress acclimation, we carried out a pilot study using the variety Desirée as a reference cultivar for our glasshouse studies in WP2. We used the PlantScreenTM phenotyping platform at the PSI Research Center in Brno (CZ) to establish cultivation and stress conditions prior to large screening experiments. This allowed us to define growth conditions, stress application, experimental design, and phenotyping protocols. We assessed the morpho-physiological traits by image-based sensors and harvested samples for downstream analyses of hormone, metabolite, marker gene and proteomics analyses by different partners. Understanding the dynamics of the stress response and the molecular pathways involved will be critical to screen selected potato cultivars out of the larger panel used in the field trials.
Additionally, 30 different varieties were screened for their response to heat- and drought stress using the established protocol of the pilot study. The results revealed genetic variance in the stress-response of different varieties and suitable parameters to rank them. Notably, the tolerance trend for some varieties correlated very well between different stresses, thus allowing us now to select common contrasting varieties for further in-depth analysis in response to different stresses.
Most important for stability of potato yield under stress conditions is the amount and the quality of potato tubers generated. Thus, the overall aim of WP3 is to unravel the complex relationship between the tuberisation signalling pathways and responses to abiotic stresses at the molecular level. We strongly benefit from previous knowledge and specific tools available in the consortium. A detailed transcriptomic analysis of transgenic potato lines over-expressing the transcriptional regulator protein SP6A was performed, revealing how SP6A expression is related to plant hormone signalling pathways. Transgenic reporter lines have been developed and analysed that are now being used to demonstrate in detail the transcriptional control of SP6A as major tuberization signal under environmental stress conditions.
We obtaining first insights into early signalling (sensory) events in potato that are responsible for the molecular and physiological acclimation to stress. To that end, two types of transgenic plants were generated: (i) sensor lines to measure secondary messengers such as calcium (Ca2+) and reactive oxygen species (ROS); and (ii) gene reporter lines to measure ROS, drought-stress responses, and stress-induced plant hormones as important regulators determining plant resistance to drought and water logging. These lines enable us to measure intracellular signalling molecules and important plant stress-related hormones such as ABA (responding to drought) and jasmonate (responding to different stresses) in our reference cultivar Desirée.
A key issue arising from large-scale and high-throughput studies is the analysis of large data sets. Therefore, we focused in the first period on setting up the methodological basis for the analysis in WP5. We have developed the StressKnowledgeMap App, which allows both visualisation of current knowledge in network format, reproducible insertion of novel knowledge and easy linkage to mechanistic modelling. We compiled several data analysis protocols that are now available for use by ADAPT and the broader scientific community.
Advances in plant breeding can only reach their outmost impact by direct communication with different target groups and stakeholders. Thus, the Plan for the Exploitation and Dissemination of Results (PEDR) was developed as a first task in WP6 and is continuously updated to guide the direct implementation at the breeders for validation of generated research results and to engage with end-users. The latter included a farmers’ perception survey involving more than 550 European potato farmers. The responses underlined the urgent necessity to support the development of abiotic stress-tolerant potato varieties and the relevance of the ADAPT project to the current situation.
• High-Throughput-Phenotyping (HTP) and bio-imaging technologies are continuously optimized to monitor physiological and morphological changes in germplasm selected by the breeders.
• Novel reporter lines are exploited to detect dynamic changes in decisive signalling pathways and multiple omics methods are used as unbiased high-throughput shotgun approaches to identify (lead) traits.
• All data will feed into big data analysis and modelling to identify new lead traits that will be validated for their usefulness in developing improved stress-tolerant potato varieties.
• The feedback of end-users shows that the results of the project will be of major benefit in the times of climate change.