Effects of sodium azide and some amino acids on callogenesis of khardel brassica nigra

الملخص EN

investigate the effects of the mutagen Sodium Azide (SA) and the amino acids L-phenylalanine, L-tryptophan, L-methionine or their combinations on callus induction of Brassica nigra.

Khardel seeds were soaked in phosphate buffer, 2 mM (SA) and 3 mM (SA )for 1hr.

Calli were induced from cotyledon leaves which were excised from the treated seeds and cultured on MS medium supplemented with 2.5mg / L 6-benzylaminopurine (BA), 0.5mg/L naphthalene acetic acid ( NAA ) and 0.5mg/L2, 4-dichlorophenoxyacetic acid (2, 4-D).

Amino acids were added to the callus induction media.

The experiment was conducted in Completely Randomized Design (C.R.D) with 5 replications.

The data were analyzed by GenStat software program.

The results showed that (SA) has negative effect on seeds germination and the highest percentage was 65% from phosphate buffer treatment (control).

However, the percentage of callus induction was the highest at 2mM (SA) by 93.21% and it was significantly different from the other treatments.

The results also indicated that L- tryptophan with L-methionine gave 100% callus induction compared with L-methionine alone which gave the lowest value 58.33%.

Moreover, highly significant differences in callus fresh and dry weights were obtained from phosphate buffer treatment on medium supplemented with L-tryptophan which gave 607.0 mg and 91.75 mg respectively compared with L-tryptophan and L-methionine combination which gave the lowest values of 66.0 mg and 10.0 mg respectively.

In conclusion, phosphate buffer and (SA) affected seed germination whereas 2mM SA stimulated callus induction from cotyledon leaves.

Moreover, L-tryptophan and L-methionine have positive effects on callus induction and proliferation.