Beneficial bacteria help plants cope with drought stress

Climate change is making droughts more frequent and severe in many parts of the world. That pose a serious threat to agriculture and food production. To mitigate this problem, a promising approach to help plants with drought is using beneficial bacteria.

– Certain bacteria, known as plant growth-promoting rhizobacteria, live in the soil and form a symbiotic relationship with plants. These bacteria can help plants withstand environmental stresses such as drought. They do this by influencing plant hormone levels, improving root growth, and enhancing the soil microbiome, says Ramesh Vetukuri.

Taller tomatoes with stronger stems

In a new study, researchers from SLU and the University of Catania in Italy, have tested a group of these rhizobacteria on the model plant Arabidopsis thaliana and on tomatoes. The researchers created a synthetic microbial community consisting of five different bacterial species with growth-promoting abilities. They tested how these bacteria affected plant growth, root structure, and the composition of microbial communities in the soil.

In Arabidopsis, the plants treated with the rhizobacteria maintained healthy root structures when faced with drought. Some bacteria even promoted the formation of structures that are essential for water transportation. When tomatoes were treated with rhizobacteria, the plants grew taller and had stronger stems. In addition, in some cases, fruit yield and quality were enhanced.

Treated plants had a more diverse soil microbiome

In general, drought stress reduces the diversity of the beneficial microbes that occurs naturally in soils.

– However, the treated plants in the study had a richer and more diverse soil microbiome. This suggest that our rhizobacteria help stabilize soil communities under stress. Different bacterial treatments led to distinct changes in the microbial composition, indicating that each strain interacts in a unique way with the plant’s natural microbiome.

– Unlike chemical fertilizers or genetic modifications, solutions based on growth-promoting rhizobacteria work in harmony with natural plant processes and soil ecosystems. As climate change continues to challenge global agriculture, microbial-based solutions could become an essential tool for farmers, reducing crop losses while maintaining soil health. Further research and field trials will help finetune these bacterial treatments for real-world applications, concludes Ramesh.