Effect of spermidine on in vitro gynogenesis of six onion accessions from Khorasan province

In order to investigate the effect of two spermidine concentrations (0.5 and 1 µ M) on in vitro gynogenesis of six onion accessions from Khorasan province this research was carried out. Results showed that the highest and lowest percentage of gynogenesis rate was belonged to M2 and M5 media, respectively. The highest (1.41) and lowest (0.33) percentage of gynogenic embryo were belonged to Roshnavand-e- Birjand and Sefid-e- Naishabur accessions, respectively. The highest percentage of plant regeneration was belonged to Roshnavand-e- Birjand accession in M2 medium culture. Ashkhane-e- Bojnourd and Dargaz accessions had the highest and lowest percentage of plant survival rate (81.25 and 49.8, respectively). Therefore, spermidine in two concentrations of 0.5 and 1 µ M, without other plant growth regulators, had no positive effect on onion gynogenesis and should not be used instead of 2,4-D and BA. Combination of spermidine with other plant hormones could induce gynogenesis in onion.