H224 + 225 Coating van vlinderbloemige-zaden met droogte tolerante Rhizobium bacteriën

Drought tolerance is an important bacterial trait for survival in terrestrial habitats, like soil. We postulate that this trait is genetically determined in bacteria and that it is especially of importance for bacteria that do not produce resistant endospores.

The Rhizobium-group of bacteria, to which species of the genera of Rhizobium, Bradyrhizobium and Mesorhizobium belong to, are relevant for agriculture because they fix atmospheric nitrogen in symbiosis with roots of Leguminous plants. To increase the chance to obtain drought tolerant forms of these bacteria, we isolated bacteria from the rhizosphere of Indigofera argenta, a plant that amongst other places grow in the deserts of Saudi Arabia. From this soil we isolated Rhizobia species and tested these for drought tolerance via comparison with a commercially applied Rhizobium strain. It is our intention to sequence the genomes of these strains and to search for genes, regulons and operons that can be hold responsible for drought tolerance. We expect that the mechanism behind drought tolerance rely on the production of particular types of exopolysaccharides (slime) that protect cells against drought (matrix stress). This feature can be of importance for commercial applications as cross-protecting agent for plant growth promoting micro-organisms against
drought stress.