Long-distance signaling and communication between different organs of a plant is essential not only for the development and growth of the plant body, but also to adequately respond to unfavorable growing conditions. Higher plants coordinate and integrate the growth and development of their tissues and organs via sensory systems that result in the production of chemical, protein, nucleic, hydraulic, and electrical signals. These signal are transported from one part of the plant to another using vasculatures. To examine the impact of these molecules on either the aeral or the root system, we adopted the technique of genetic grafting, which consists in altering a signal on one part of the plant (Genetically Engineered) and in evaluating the impact on the other part (Non Genetically Engineered).  

         We are using two  models in the lab to study this topic.

• The first  model is the microvine/grapevine model because of the extensively use of rootstock/scions in grapevine production. Several aspects of grapevine production including water stress, nutrient deficiency (Nitrogen, salt exclusion), and soil-borned disease strongly relies on the use of rootstock and scion. However, the genetic basis that confer tolerance to abiotic stresses such as drought, salt tolerance, and nutrient deficiency is still poorly understood. Root-to-shoot and shoot-to-root communications are important determinants in response to abiotic stresses (Figure 4). Though, there is no clear evidence to ascertain a prevailing role of the belowground part relative to the areal part on conferring the stress tolerance As first step, we have focused on the study of the two major signals (chemical and hydraulic signals) in the context of drought. Our objectives are i) to understand their respective contribution to the grapevine response to drought, ii) to examine their interplay in the context of drought, and iii) to evaluate the influence of genetic in the perception and the level of resposne to these signals.
• The second model is Brachypodium Distachyon. Our research question is oriented towards the influence of strigolactones, a plant hormone, on the control of  root and shoot branching and the likely interplay of this class of regulators with other hormones under the context of nutrient deficiencies (Phosphate and Nitrate) and drought.

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