INHERITED ALTERATION UTILIZING THE COTYLEDONARY NODE OF PEANUTS (ARACHIS HYPOGAEA L.) AS A TRANSPLANT AND A PROMOTER-LESS GUS::EPSPS FUSION GENE-DERIVED VECTOR

This study focused on Agrobacterium-mediated transformation to develop potential transgenic lines of Arachis hypogaea L. using the promoterless GUS::EPSPS -glucuronidase::5-Enolpyruvylshikimate 3-phosphate synthase gene and cotyledonary node (CN) explants.The most effective medium for inducing multiple shoot buds was Murashige and Skoog (MS) medium containing 0.4 mg/L BAP (6-benzylaminopurine) and 0.1 mg/L NAA (-naphthaleneacetic acid).Investigations were conducted on parameters increasing genetic transformation, such as seedling age, co-cultivation periods, and Agrobacterium genetic background.Co-cultivating 6-day-old seedlings with Agrobacterium strain GV3101 for three days resulted in a 45% induction of kanamycin-resistant shoots, and GUS assays confirmed a transformation frequency of approximately 31%.Using the promoterless GUS::PxCSGm-YFP::Yellow Fluorescence Protein EPSPS construct, 38% of transient GUS expression was observed.A total of 151 T0 seedlings were generated, of which 92 survived in the greenhouse, and five plants (4.54%) exhibited stable gene integration as confirmed by Southern blot, PCR, and GUS assays.GUS-positive expression was observed in 24 plants, with Mendelian segregation patterns identified in 15 T0 progenies.The present study identified that the variable GUS expression patterns were discovered in the transgenic lines and demonstrates the successful introduction of the GUS::EPSPS gene without a promoter, offering a promising approach for peanut genetic engineering and herbicide resistance.