Résumé
Sorghum is the fifth most important cereal grown across the world in terms of grain production. Grain and flour are used as a staple food in many low-income countries and grains and vegetative parts can also be used for animal feed, energy production or engineering of bio-based product. However, improvements are still needed to adapt varieties to specific uses and various biotic and abiotic stresses. In order to identify molecular mechanisms that could be required for those improvements, numerous transcriptomic and genetic studies are performed and increasingly available in the literature and databases. Many candidate genes have been identified and need to be validated. However, the low rate of genetic transformation efficiency for this recalcitrant species still remains an obstacle for functional genomics studies. We will present here a transient transfection protocol based protoplast using PEG-mediated method. We have overexpressed transcription factors of interest to validate their function and identified their target genes through transcriptomic studies. The aim is now to optimize a protocol of stable transformation either with immature embryos, leaf whorls or other organs. We are investing the main share of our efforts on Agrobacterium mediated transformation using immature embryos from sorghum variety Texas 430 and reporter genes, GFP and GUS.