Direct somatic embryogenesis from immature embryos of sunflower hybrids

In the present study, the effect of plant growth regulators on direct somatic embryogenesis and plant regeneration of two Iranian sunflower hybrids (Azargol and Farrokh) were examined. After the flowering, immature embryos ten day after pollination were used as explants. Immature embryos were surface sterilized and subsequently transferred to embryogenesis medium containing MS medium elements and B5 vitamins, 120 g/l sucrose and different combinations of plant growth regulators (BA in two levels,1 and 2 mg/l in combination with NAA or 2,4-D in three levels 0.1, 0.25 and 1 mg/l and 2,4-D in two levels, 0.33 and 1 mg/l. Analysis of variance showed significant differences between hybrids, hormones and hybrids×hormones interaction. The somatic embryos were first observed 10 days after culture on medium containing 120 g/l sucrose and a callus intermediate was not formed. Somatic embryos of two sunflower hybrids directly obtained on a medium supplemented with 2 mg/l BA and 0.25 mg/l NAA with more number and speed.