The current status of the genetic transformation of Arachis plants

Peanuts (Arachis hypogaea) are vegetable oil, protein and forage crops. The genus Arachis contains nine intrageneric taxonomic sections, including 83 species. Most Arachis species are wild plants widely serving as forage and turfgrass plants. Moreover, wild Arachis plants can provide gene resources for broadening genetic diversity in peanuts. To date, several key genes have been identified using recombinant inbred lines of Arachis species. The use of genetic engineering in improving peanut genetic diversity has not been popularized. This is because of the lack of a robust and reliable genetic transformation method for Arachis species. However, evidence indicates that the genetic transformation of Arachis plants had been reported 30 years ago. Therefore, there is a strong contradiction between the genetic transformation and the unsuccessful transfer of candidate genes into Arachis plants. This review summarized the Arachis regeneration and genetic transformation methods to deepen the understanding of transgenic technology in Arachis species.