Understanding crown-root initiation in barley (Hordeum vulgare L.).

Facing changes of environment and ever-increasing demand for food supply, modern breeding has to provide new crops adapted to extreme conditions or able to better cope with natural resources. The importance of the underground root system is often underestimated whereas they are fundamental for water and nutrient uptakes, two parameters which strongly affect the yield. In theory, more roots should be linked with higher ability to use the natural resources. In cereals, the root system is mainly composed of the crown-roots (CRs) arising from the base of the stem. Rice and maize are the two cereals currently used as model to study CR initiation and development. Barley is among the most economically important crops. Due to its wide geographical distribution and its fully sequenced diploid genome, barley can appear as a model for cereals of the Triticaceae tribe, including wheat and rye.

Like in rice and maize, initiation and development of CRs in barley occurs very early in the development of the seedlings, within the 3-4 days following germination. Using a multi-disciplinary approach, we tend to determine where CR initia are formed, what are the key players and which role auxin plays in this process.