To investigate the effect of sterile conditions and hormone types on the inhibition of necrosis leaf explants of African violet (Saintpaulia ionantha) in vitro culture, two independent experiments were conducted as factorial based on randomized completely design with five replications. The first experiment included two levels of 15 and 20 percent sodium hypochlorite for 10 and 15 minutes. Also, the effect of hormone types (BA (0, 0.5, 1, 2 and 4 mg/lit), 2,4-D ( 0, 0.5, 1 and 2 mg/lit) and NAA (0, 0.5 and 1 mg/lit) separately and in mixed combination) on necrosis were studied in the second experiment. The results showed that the most level of sodium hypochlorite on inhibition of necrosis was 15 % for 10 minutes and other levels did not have significant effects on it. Although contamination increased in the mentioned treatment. The most important reason for necrosis of leaf explant was using hormones included Auxins especially 2,4 -D. There was no significant difference between various concentrations of each hormone on the necrosis rate.

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