Background and Goals
As the tenth subproject within the main project “BayKlimaFit – strategies for the adaptation of crop plants to climate change”, the subproject explores the question to what extent the barley is resistant to local climatic factors coupled with resistance to biotic damaging factors? The focus lies on barley diseases of the ramularia leaf spot and spike fusarioses.
In addition, it clarifies whether the historical development of disease processes in barley can be explained by changes in the weather or climate. The results of the project can be used in the form of selected markers directly in practical plant breeding in Bavaria.
Steps in the process of adaptation to climate change
Step 1: Understand and describe climate change
- Dry periods
Step 2a: Identify and assess risks - climate effects and impact
In order to test the resistance of climate-adapted barley varieties to fungal pathogens and to optimize plant breeding for Bavaria numerous investigations were carried out: studies of historical barley patterns, field and rain-out experiments to investigate interactions between abiotic stress, basal stress resistance and the occurrence of pests under natural conditions with and without targeted infection, combination stress experiments and measurement of fusarium toxins, identification of multiple stress resistant genotypes and RNA isolation and sequencing from combination stress experiments.
In order to gain evidence of a causal link between global warming and disease incidence, Bavarian archive grain samples from the past six decades have been studied. This showed a changing over the years spectrum of Fusarium spp. in the barley and an overall increase in Fusarium and R. collo-cygni levels in the harvest samples. Overall, the trend was correlated with the rising temperatures during the growing season in Bavaria, but the association with the annual single-weather data was not strong, so that one cannot currently postulate any causal relationships between the climate data and the increase in the disease problem.
As a result, the studied diseases grow in historical patterns from the last 50 years. In addition, the Bavarian gesture genotype assortment shows a wide variety of disease resistance.
Among other things, the great diversity in Fusarium infestation of barley and influence of drought stress is detected.
According to studies and experiments, it can be stated that the barley species-dependent / genotype-dependent on drought stress with altered disease resistance. Drought stress after infection affects and increases susceptibility to Fusarium spp.
Further findings indicate that the permanent dryness in the field / rolling greenhouse suppresses the ramularia (remularia leaf spot) of the barley varieties.
Step 4: Plan and implement measures
The results of the project lay the basis for the breeding of climate-adapted summer barley genotypes with good resistance to barley diseases. The resistance of winter barley still needs to be explored.
Bavarian Ministry of the Environment and Consumer Protection
Technical University of Munich