Periodic Reporting for period 2 - RESIST (Resurrection plants reveal secrets of vegetative desiccation tolerance)
Periodo di rendicontazione: 2021-03-01 al 2024-08-31
A major challenge faced by modern agriculture is plant stress caused by the unfavourable environmental conditions. Global warming is predicted to further intensify these problems, including increasing the frequency and severity of drought stress, which seriously affect both crop quality and yield. Therefore, timely action is needed to find solutions to mitigate the consequences of water deprivation in plants. A small number of species called resurrection plants can tolerate desiccation of their vegetative organs and are a natural resource that can be tapped to solve this problem. They can withstand transition to air-dried state and completely restore physiological activities upon rehydration. Moreover, some of these resurrection species are shown to tolerate other stresses, including low temperature/freezing, severe oxidative stress, and long-term darkness. Therefore, research on resurrection plants has not only significant fundamental scientific importance, it has also immediate practical application, especially in the context of growing population and the ever-increasing demand for higher quality and sustainably produced foods. The interest in these unique plants is additionally fueled by the identification of compounds from resurrection species with medicinal (anticancer and antiviral) activities. However, still little is known about the organization of their genomes and the genetic mechanisms that determine their exotic physiology.
The characterization of the genomes of resurrection species, and the identification and functional characterization of important desiccation gene networks, could bring valuable information about the molecular mechanisms of abiotic stress tolerance and identify new strategies that can be used for crop improvement. Therefore, the major goal of this project is to unravel the genetic determinants of desiccation tolerance in resurrection plants and to identify similarities and differences with model and crop species. The newly acquired fundamental knowledge on resurrection plants will be translated to economically important species. A secondary objective will be to explore the possibility of integrating seaweed based stress mitigation technology to improve crop tolerance to drought.
The characterization of the genomes of resurrection species, and the identification and functional characterization of important desiccation gene networks, could bring valuable information about the molecular mechanisms of abiotic stress tolerance and identify new strategies that can be used for crop improvement. Therefore, the major goal of this project is to unravel the genetic determinants of desiccation tolerance in resurrection plants and to identify similarities and differences with model and crop species. The newly acquired fundamental knowledge on resurrection plants will be translated to economically important species. A secondary objective will be to explore the possibility of integrating seaweed based stress mitigation technology to improve crop tolerance to drought.
- The genomes of three resurrection plant species, Haberlea rhodopensis, Xerophyta elegans and Xerophyta humilis, were de novo sequenced, assempled and anotated. Comparative genomics studies demonstrationg the common and specific features of these and other genomes, including desiccation sensitive plants, have been carried out.
- A group of seven large experiments with various conditions, resulting in more than a dozen of matched –omics datasets (transcriptomics, metabolomics and lipidomics) of the 4 studied resurrection species in the project, was carried out:
1) A detailed desiccation/rehydration curve for H. rhodopensis;
2) A desiccation curve experiment with adult X. elegans plants;
3) A desiccation/rehydration study with 14 sampling data points with X. elegans seedlings;
4) A similar experiment with 14 data points with X. schlechteri seedlings;
5) Perturbation of X. elegans seedling development with low and high PEG concentrations;
6) A comparison of X. elegans, X. schlechteri and X. humilis at the early and late stage (two-leaf) seedlings.
7) An experiment with H. rhodopensis treated with low temperatures (chilling, freezing), desiccation and their combinaions. In addition, the metobolomic footprints of H. rhodopensis subjected to darkness, desiccation and their combination was also studied.
- Based on the experiments mentioned above, a list of candidate genes for functional analysis from H. rhodopensis has been made and the work on the first of them initiated. Transcription factors suitable for functional analysis, since they were upregulated either during the early or late stages of dehydration in both X. elegans and X. schlectheri seedlings were, were identified.
- A study on the regulatory role of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) for desiccation tolerance in X. humilis was also carried out.
- Apart from the resurrection species, experiments on nine crops have also been performed with the aim to study their stress resilience and methods for their yield improvement: tomato, pepper, eggplant, potato, lettuce, raspberry, barley, blueberry and onion. A molecular priming technology, based on the application of a natural seaweed-based biostimulant, to mitigate stress symtoms and increase the yield was shown effective in most of the cases.
- The desiccation tolerance of wild and culticvated barley seedlings was studied in a large population. The heritability, genomic predictability and metabolomic markers which are associated with recovery rate after dehydration in barley seedlings were characterized.
- A genome-scale metabolic network (GEM) model for X. elegans was generated.
- An ambitious comunication campaign was launched to communicate the project objectives, expected results and impact to various stakeholders. As a result, hundreds of thousands people were informed, especially due to open-air exhibitions in Plovdiv and the media (both printed and social) coverage.
- A total 9 online education events, which were made open to researchers from all over the world, were organized. In addition, a conference dedicated to the biology and significance of angiosperm resurrection plants was held in Bulgaria.
- A group of seven large experiments with various conditions, resulting in more than a dozen of matched –omics datasets (transcriptomics, metabolomics and lipidomics) of the 4 studied resurrection species in the project, was carried out:
1) A detailed desiccation/rehydration curve for H. rhodopensis;
2) A desiccation curve experiment with adult X. elegans plants;
3) A desiccation/rehydration study with 14 sampling data points with X. elegans seedlings;
4) A similar experiment with 14 data points with X. schlechteri seedlings;
5) Perturbation of X. elegans seedling development with low and high PEG concentrations;
6) A comparison of X. elegans, X. schlechteri and X. humilis at the early and late stage (two-leaf) seedlings.
7) An experiment with H. rhodopensis treated with low temperatures (chilling, freezing), desiccation and their combinaions. In addition, the metobolomic footprints of H. rhodopensis subjected to darkness, desiccation and their combination was also studied.
- Based on the experiments mentioned above, a list of candidate genes for functional analysis from H. rhodopensis has been made and the work on the first of them initiated. Transcription factors suitable for functional analysis, since they were upregulated either during the early or late stages of dehydration in both X. elegans and X. schlectheri seedlings were, were identified.
- A study on the regulatory role of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) for desiccation tolerance in X. humilis was also carried out.
- Apart from the resurrection species, experiments on nine crops have also been performed with the aim to study their stress resilience and methods for their yield improvement: tomato, pepper, eggplant, potato, lettuce, raspberry, barley, blueberry and onion. A molecular priming technology, based on the application of a natural seaweed-based biostimulant, to mitigate stress symtoms and increase the yield was shown effective in most of the cases.
- The desiccation tolerance of wild and culticvated barley seedlings was studied in a large population. The heritability, genomic predictability and metabolomic markers which are associated with recovery rate after dehydration in barley seedlings were characterized.
- A genome-scale metabolic network (GEM) model for X. elegans was generated.
- An ambitious comunication campaign was launched to communicate the project objectives, expected results and impact to various stakeholders. As a result, hundreds of thousands people were informed, especially due to open-air exhibitions in Plovdiv and the media (both printed and social) coverage.
- A total 9 online education events, which were made open to researchers from all over the world, were organized. In addition, a conference dedicated to the biology and significance of angiosperm resurrection plants was held in Bulgaria.
Progress:
- Originally, the project planned the sequencing and assembly of 2 genomes of resurrections pecies, H. rhodopensis and X. humilis. However, this was achieved for one additional species - X. elegans. The genomics resources are available to the entire scientific community working in this field.
- Multiple matched -omics datasets for parallel transcriptomics, metabolomics and lipidomics in H. rhodopensis, X, elegans, X. schlechteri and X. humilis were generated and analyzed.
- An Ascophyllum nodosum-based biostimulant was demonstrated to successfully induce mitigation of various stress effects and increase the yield in multiple crops.
- Based on the analysis of the generated databases, a list of 14 genes related to responses to extreme conditions in Haberlea rhodopensis and 4 transcroption factors associated with desiccation tolerance in Xerophyta was prepared and the functional analysis to verify their role was initiated. This work will continue after the project as well.
Impacts:
- The comparative genomics of extremophiles helped define novel genes and expanding gene families that contribute to the adaptation to stresses.
- The generated matched –omics datasets (transcriptomics, metabolomics and lipidomics) from experiments with the target resurresction species are a very useful resource for future comparative and functional studies, including from other research groups, to pinpoint the mechanisms of vegetative desiccation tolerance in plants.
- The knowledge from resurrection species may be translated to crops in the future in order to boost their resilience.
- The transfer of knowledge task (secondments of 33 people) improved the human capacity in the partner institutions.
- Originally, the project planned the sequencing and assembly of 2 genomes of resurrections pecies, H. rhodopensis and X. humilis. However, this was achieved for one additional species - X. elegans. The genomics resources are available to the entire scientific community working in this field.
- Multiple matched -omics datasets for parallel transcriptomics, metabolomics and lipidomics in H. rhodopensis, X, elegans, X. schlechteri and X. humilis were generated and analyzed.
- An Ascophyllum nodosum-based biostimulant was demonstrated to successfully induce mitigation of various stress effects and increase the yield in multiple crops.
- Based on the analysis of the generated databases, a list of 14 genes related to responses to extreme conditions in Haberlea rhodopensis and 4 transcroption factors associated with desiccation tolerance in Xerophyta was prepared and the functional analysis to verify their role was initiated. This work will continue after the project as well.
Impacts:
- The comparative genomics of extremophiles helped define novel genes and expanding gene families that contribute to the adaptation to stresses.
- The generated matched –omics datasets (transcriptomics, metabolomics and lipidomics) from experiments with the target resurresction species are a very useful resource for future comparative and functional studies, including from other research groups, to pinpoint the mechanisms of vegetative desiccation tolerance in plants.
- The knowledge from resurrection species may be translated to crops in the future in order to boost their resilience.
- The transfer of knowledge task (secondments of 33 people) improved the human capacity in the partner institutions.