The Roots of a New Green Revolution

Previous Green Revolution VS New Green Revolution

For New Green Revolution - Nutrient uptake - Nitrogen fixation - Root architecture

Root System Uptake of Nutrients and Water Anchorage in the Substrate Interaction with Symbiotic organisms Optimal Growth Yield of Crops

What are the major challenges? Due to climate change, plant roots and their habitats have a high risk of becoming subjected to unfavorable conditions ex) water scarceness, increasing ground water salinity, decline in soil nutrients

What are the major challenges? 1. The conversion of unsuitable soil to arable land will require agricultural techniques. 2. those soils will require crops which are able to deal with the awkward edaphic and climate conditions. 3. A major challenge will be to connect and combine those various genes and pathways.

Can we tackle the emerging problem? Starting with fundamental analyses in the model plant it should be possible to fulfill the requirements to contribute to an increased and more efficient root system Here, we will summarize the current status of our knowledge

Root growth, branching and surface Currently, the most investigated regulator of root growth and branching is the plant hormone auxin. In addition, a fine-tuned control of cytokinin catabolism provides another means to influence root branching and mass

Improved uptake and fixation of nutrients A number of root-associated processes that establish upon mutual chemical signal perception lead to a better fixation of these nutrients The fungal network tremendously increases the root surface area for nutrient uptake are transferred to the plant via active transport mechanisms along the peri-arbuscular membrane, a process that is crucial to sustain symbiotic interaction

Improved uptake and fixation of nutrients The components required to establish and maintain symbiosis can be one of the most attractive players to manipulate and improve root surface and nutrient uptake. Better knowledge and understanding as well as new insights with potential to improve symbiotic performance and symbiosis-required signaling cascades will contribute significantly to sustainable agriculture.

Can we avoid genetically modified organisms? Plants adapt to an undesirable environment, thanks to their enormous phenotypic plasticity Hence, one can make use of genetic traits and diversity that are present in natural populations, analyzing various ecotypes and identifying the responsible quantitative trait loci (QTLs), which can subsequently be combined through classical breeding.

Future research directions Negatively affects other traits Unclear how to balance Downside of changing tra its Make use of new modeling technologies to dissect complex phenotypes & to predict which combinations are favorable Make use of new modeling technologies to dissect complex phenotypes & to predict which combinations are favorable

Future research directions Various shoot branching genes, strigolactones Cluster roots (to maximize phosphate) Communication between root and shoot - Auxin, - HAR1, peptides - BPS1 The nodule developmental program had been hijacking root formation molecular components. - LAPD/NIP

Future research directions Strigolactone Cluster roots Auxin HAR1 BPS1 LATD/NIP

Future research directions Perennial plants wit h long-living root sys tems Uniform growth conditions Future research

Concluding remark 1. The focus should be on improving the root system 2. We need to combine conventional breeding techniques, molecular biology, genetic engineering and nature variation. 3. Achieving these goals will also require an enormous effort on a political, economical and social level.