Cold Response Dynamics in the Maize Leaf Growth Zone.

Early spring cold is a major limiting factor for maize cultivation in North-Western Europe. Typically, cold spells are only transient and it is known that the capacity of varieties to recover strongly determines their final yield. Nevertheless, in contrast to the direct response to adverse conditions, the mechanisms involved in the recovery of growth have scarcely been studied. This project addresses this critical lack in our knowledge, using an innovative experimental setup where transient exposures to cold are applied at different stages of the development of the 4th leaf of maize lines with contrasting cold tolerance. Advanced phenotyping will be used to quantify the effect on the elongation growth of the leaf, during the cold and upon recovery until the leaf stops growing. Kinematic analysis will be used to quantify the cellular basis of the growth response and recovery. We will determine the molecular changes in the leaf growth zone during the response and recovery phase by means of mRNA sequencing, antioxidant and carbohydrate metabolites analysis and biochemical assays. At the physiological level we will determine the response of photosynthesis and water-relations. Based on this comprehensive and integrated analysis, candidate recovery genes will be identified and mutant and transgenic lines with altered expression of these genes will be acquired and studied in our experimental setup and under field conditions. The obtained knowledge will be scientifically innovative and relevant for plant breeding.

Keywords:PLANT DEVELOPMENT, PLANT PHYSIOLOGY, PLANT GROWTH REGULATION, PLANT MOLECULAR BIOLOGY

Disciplines:Plant cell and molecular biology