Soil is a home for an unbelievable diversity and abundance of microbial life that is essential for supporting life on our planet. Microorganisms living in soil take part in cleaning our water,... Show moreSoil is a home for an unbelievable diversity and abundance of microbial life that is essential for supporting life on our planet. Microorganisms living in soil take part in cleaning our water, degrading toxic compounds and recycling nutrients, and last but not least, they are essential partners to plants. Through their roots, plants release a mix of secretions to attract microorganisms, creating a remarkable environment called the rhizosphere. The rhizosphere is populated by microbes who often provide beneficial services to plants, like nutrient acquisition, growth promotion and protection against diseases. Modern agriculture suffers from losses caused by crop diseases, and a common way of controlling diseases is using pesticides. Pesticides often have a negative impact on the environment, and disease-causing agents (pathogens), can become resistant with time. One of the possible solutions to this problem is based on soil microbial communities. Due to the activity of their microbiome, some soils possess a natural capacity to protect plants against diseases. These soils are called disease suppressive soils, and the investigation of the microbial mechanisms leading to the natural protection of crops is the topic of this thesis. In our work we used a common pathogen of cereals, fungus Fusarium culmorum, and wheat, to first, identify suppressive soils able to protect this plant from the pathogen, and, investigate the mechanisms of protection using e.g. sequencing and mass spectrometry. During our project we identified potential microbes, genes and metabolites involved in soil disease suppressiveness. Moreover, we evaluated the impact of microplastic on the soil disease suppressiveness. Show less
The overall objectives of my thesis are to investigate the dynamics of the sorghum root microbiome and to explore the beneficial effects of the root microbiome on sorghum growth and stress... Show moreThe overall objectives of my thesis are to investigate the dynamics of the sorghum root microbiome and to explore the beneficial effects of the root microbiome on sorghum growth and stress tolerance. In Chapter 2, I describe the differences in rhizobacterial community composition of seven different sorghum cultivars grown in the greenhouse in two different soil types at four different plant growth stages. in Chapter 3 I present the co-occurrence of bacterial and fungal communities in the rhizosphere of different sorghum cultivars. Chapter 4 addresses the effects of different rhizobacterial community compositions on growth and drought tolerance of sorghum. In Chapter 5, I described the effects of five endophytic bacterial strains on the growth of four sorghum cultivars. In Chapter 6, I provide a general discussion of the main findings of this thesis and highlight the importance of sorghum-microbiome interactions. Show less
