Transformation of maize ( Zea mays L.) by Agrobacterium Tumefaciens and shoot apical meristem explant

The aims of study were to investigate callogenesis and regeneration of the studied cultivars and also exploring the possibility of gene transfer into maize by using complete bud and stem apical meristem explants. Material and methods: Complete bud and stem apical meristem of six cultivars were used as explants on MS medium + 5 mg.L-¹ 2,4-D. For regeneration, calluses were cultured in MS including 1 mg.L-¹ Kn and 10 mg.L-¹ BAP. According to the results of tissue culture, SC703 and SC704 cultivars were selected for gene transfer. Transformation of explants was done with LBA4404 strain of Agrobacterium tumefaciens containing pBI121 vector. To investigate the transgenic nature of the samples, PCR and histochemical assay were used. Callus induction was taking place after 30 to 40 days and the frequency of callus induction in six cultivars was 100%, in addition the highest rate of regeneration (90 %) was observed in stem apical meristem explants of SC704. In some cultivars, stem apical meristem explants were more suitable, although in other cultivars, complete bud explants were better. PCR results for NPTII gene and GUS histochemical assay showed that some calli are transgenic and GUS gene is expressed. The results of callogenesis, regeneration and genetic transformation showed that SC 704 was better than the others.