Effect of Hormonal Regime and Explant Type on Cell Clusters Expression of Maize Mutants (Zea Mays L) Derived from Gamma Irradiated Seeds of Ev8728 variety

Maize (Zea mays L.) seeds irradiated with gamma or not from the fourth self-fertilisation cycle were selected for tissue culture. For this purpose, MS medium supplemented with 30 g.L-1 sucrose, 100 mg.L-1 casein hydrolysate, 100 mg.L-1 myo-inositol and 6 g.L-1 agar was used. For this purpose, three auxins type (2.4-dichlorophenoxyacetic acid (2.4-D), 2-methoxy-3.6-dichlorobenzoic acid (Dicamba) and Indole-3-Acetic Acid (AIA)) and explants (root, epicotyl and leaf) were tested. The results showed that 2.4-D more precisely at 3.5 mg.L-1 was the best auxin for callus induction in the different maize mutants studied. The induction rate, dry matter weight and water content of callus varied according to the type, age, explant position and the maize mutants studied (control, 200 and 300 grays). Thus, the 7-day root and more precisely its basal part was better for callogenesis. In addition, mutants of the 200 grays dose were more expressive in the ability to induce callus in EV8728maize variety.