Final Report

Within this FWF funded Project, multilevel analyses and technological developments allowed the research group around Stefanie Wienkoop to describe so far unknown molecular mechanisms. In legumes (e.g. pea and bean) this mechanisms play fundamental roles for improved drought stress tolerance.

Legumes are able to establish beneficial interactions (symbiosis) with rhizobia. The scientists found that this plant-rhizobia interaction plays a key role within stress response. Leaf senescence, induced by water deficiency, was decelerated through symbiotic interaction. This slowed senescence process, also called stay-green effect has also been observed in agriculture, but is not fully understood until now.

Drought stress is a major cause for crop loss and thus plays an important role in the course of climate change. Legumes are principal source of protein nutrition for human. The directed application of specific rhizobia as a substitute for nitrogen fertilization may reduce costs in addition to improved drought stress tolerance.

Besides a symbiotic priming effect that changed the molecular background of the plants (similar to inoculation), the team found some putative key molecules that may be relevant for future application in biotechnology towards improved stress tolerance. These insights may also be transferable to other plant families. Some of those key molecules have already been selected for further research.

HIGHLIGHTS - Summary 

♦ Discovery of the drought triggered microbial "Symbiont Induced StrayGreen" (SISG) effect
- delayed leaf senescense during drought
- rapid recovery from drought
♦ Development of a software tool for the automated mass spectra extraction of partial 15N metabolic labelling experiments for high throughput protein turnover analyses
♦ Disclosure of two independent processes for drought and drought-recovery