Abiotic Stress Resistance and Resilience
The sustainable use of Earth’s resources in a changing environment is a main challenge for the preservation of livelihood and human health. Climate change will significantly alter factors of agricultural production in the coming years. Changes in temperature and precipitation associated with sustained emissions of greenhouse gases are in conflict with sustainable agriculture and will affect crop and biomass yield. This will constrain agricultural productivity to meet the demand of the steadily increasing population worldwide. For maintaining sustainable, environmentally benign agriculture under the forecasted future climate conditions, it is essential to design effective plant breeding and protection strategies, principally exploiting the available genetic resources.
Our research will in particular unravel the following questions:
- What are the underlying mechanisms and driving forces determining resource use efficiencies (water and nutrients) and how do these traits affect plant quality and plant fitness under the predicted future environmental conditions?
- How do constitutive and stress-induced constituents contribute to plant growth and biomass production?
- How do genes and phenomic traits contribute to plant growth and development under multiple environmental impacts (water availability, temperature, air pollutants, and UV-B radiation)?
The sustainable use of Earth’s resources in a changing environment is a main challenge for the preservation of livelihood and human health. Climate change will significantly alter factors of agricultural production in the coming years. Changes in temperature and precipitation associated with sustained emissions of greenhouse gases are in conflict with sustainable agriculture and will affect crop and biomass yield. This will constrain agricultural productivity to meet the demand of the steadily increasing population worldwide. For maintaining sustainable, environmentally benign agriculture under the forecasted future climate conditions, it is essential to design effective plant breeding and protection strategies, principally exploiting the available genetic resources.
Our research will in particular unravel the following questions:
- What are the underlying mechanisms and driving forces determining resource use efficiencies (water and nutrients) and how do these traits affect plant quality and plant fitness under the predicted future environmental conditions?
- How do constitutive and stress-induced constituents contribute to plant growth and biomass production?
- How do genes and phenomic traits contribute to plant growth and development under multiple environmental impacts (water availability, temperature, air pollutants, and UV-B radiation)?
Our Projects:
The evolution of terrestrial plant life was probably enabled by the development of a stratospheric ozone layer, which absorbes completely all of the short and harmful ultraviolet radiation (UV-C 100 - 280 nm) and to some extent the short wave part of UV-B radiation (280 - 315 nm) of the solar spectrum reaching the earth’s surface.
Because UV-B radiation can cause structural changes in nucleic acids, proteins, and other macromolecules of all organisms, plants have developed structural, chemical and biochemical mechanisms to minimize detrimental impacts of UV and efficiently repair UV-induced cellular damages. Research of EUS, in cooperation with the Institute of Biochemical Plant Pathology (BIOP), focuses on the biochemical mechanisms and chemical structures of UV-screening pigments of plants. Particulary, we analyze UV-B dose-dependent accumulation patterns of phenolic compounds (e.g. flavonoids, hydroxycinnamic acid derivatives) in combination with other environmental constraints like temperature, air pollution (ozone) and water shortage/drought.
Climate change has numerous and only rudimentarily understood impacts on plants in natural and agricultural ecosystems. The increase in CO2 emissions resulting from the use of fossil fuels is responsible for the anthropogenic greenhouse effect. Ground-level ozone formed by photochemical reactions of nitrogen oxides and hydrocarbons, nitrogen oxides themselves and other emissions such as particulate matter, are an increasing burden on humans, animals and plants. Under global change the competitiveness of plants in the ecosystem as well as its stability can therefore change.
The spectral solar radiation used by plants not only serves as an energy source for photosynthesis, but also regulates various adaptation strategies to changing environmental conditions with a multitude of receptors. Indoors experiments must therefore take place under a radiation simulation which is as close to nature as possible (Döhring et al. 1996). In addition to the absolute level of irradiation, a realistic ratio of the spectral components from the UV (290-400) to the visible range (400-700 nm) to the NIR (700-1000 nm) is particularly important. Since these conditions depend on the position of the sun, the lighting system must take into account not only the daily course of irradiation, but also the changing spectrum over the season.
At present, the global radiation (sum of direct and diffuse solar irradiation) in the climate chambers at HMGU, from the ultraviolet (UV) to the near infrared (NIR) spectral range, is realized using conventional illumination technology and is based on metal halide lamps (Osram HQI 400 W), quartz halogen lamps (Osram Halostar 400 W), blue fluorescent tubes (Philips TLD 18/36 W) and UV-B fluorescent tubes (Philips TL 12/40 W) (Döring et al. 1996).
This project aims to develop a new, state-of-the-art, energy-efficient lighting system which can simulate the natural spectrum of the sun from UV to NIR in the visible spectral range using a wide range of LEDs (Light Emitting Diodes). The aim is to design a system which can simulate both the annual/daily variation of solar radiation as well as short-term fluctuations in irradiation and spectrum, e.g. caused by clouds. Changes in the spectral composition in photobiologically effective areas also allow targeted functional studies of photobiological processes against a natural radiation background. Additionally the new system should be able to produce an artificial light spectrum which already is being used in greenhouses for food production. This would also allow studies on the influence of certain wavelength on food-plants regarding the phenotype and metabolic composition.
The project "Adaptation potential in oaks to biotic and abiotic stresses under climate change" (Survivor-oaks) is funded in the frame of "Waldklimafonds" by the Federal Office for Agriculture and Food (Förderzeichen 2220WK09B4; 2021-2025).
For the last decades, forest ecosystems have been exposed to increasing abiotic and biotic stresses associated with global warming. Long-living plant species (i.e., trees) are particularly vulnerable to rapid climate changes. This joint project between the Thünen Institute of Forest Genetics (TI) and Helmholtz Zentrum München (HMGU) aims to develop silvicultural recommendations for cultivating new climate-adjusted forests and provide plant material suitable for breeding. This project, in particular focuses on Quercus robur, commonly known as common oak, pedunculate oak, European oak or English oak, which shows a relatively high adaptive potential and, therefore, provides a beacon of hope for European forests under changing climate conditions.
Our ultimate goal is to collect high-fitness Q. robur genotypes characterized by drought tolerance and/ or increased resistance to herbivores and fungal parasites and organize a future-climate oak seed plantation in Germany. For this purpose, we develop genetic markers for the Q. robur tolerance to abiotic and biotic stresses relevant to climate change, such as drought, insect attacks, and fungal infections using integrated analyses of genotypic, phenotypic, and environmental data. To establish drought tolerance markers at HMGU, genomic data will be generated for a Germany-wide collection of Q. robur genotypes and analyzed in a combination with the climate data available from Deutscher Wetterdienst (DWD) stations using genome-environment association methods. In addition, already existing pool of genotypes from different climate zones in Germany growing in a Common Garden at TI will be experimentally tested for tolerance to drought (HMGU), herbivore-generalist Lymantria dispar (TI), and powdery mildew agent Erysiphe alphitoides (fungal disease). New Generation Sequencing (NGS) data will be generated for the experimentally detected extreme phenotypes and used for the marker development. A resulting set of genetic markers will be employed for selecting advantageous Q. robur genotypes for the future-climate seed orchard.
