Abstract
Arachis hypogaea, or the groundnut/peanut, is native to South America and is one of the most important legume crops, prized for its high protein and fat content. It exhibits a unique dispersal strategy known as geocarpy ("soil fruiting"): after flowering, fertilized ovules are pushed underground to mature near the parent plant. The developing carpophore ("fruit carrier") has characteristics of both stem and root. Initially gravitropic like a root, it also contains chloroplasts and stomata like a shoot. Once underground, the carpophore shifts to a skotomorphogenic response. After a few centimeters, its elongation halts, and embryonic growth resumes, leading to the formation of the peanut fruit. We are currently assessing transformation procedures for the peanut plant to enable the investigation of the molecular mechanisms that drive these distinct stages of geocarpic growth. Our focus is on reprogramming individual steps to explore the interdependencies of these pathways.