Silver nitrate is essential for successful regeneration of Egyptian sunflower (Helianthus annus L.) cv. Giza 102

Sunflower (Helianthus annus L.) is an important source of vegetable oil. Egypt relies almost entirely on importation of vegetable oils due to limitation of land and competition with other warm-season more profitable crops. In the present study, cotyledons dissected from 24 hr germinating seeds were tested on 16 different media. The highest shoot-buds formation was on medium fortified with 0.5 mg/l naphthalene acetic acid and 1.0 mg/l benzyl adenine, yet no further development was observed. Healthy shoots only developed after adding 5.0 mg/l silver nitrate to the regeneration medium; while shoot elongation was achieved on a medium fortified with 0.05 mg/l indol acetic acid and 5.0 mg/l silver nitrate. Root formation was possible when using a low-salt medium with indol acetic acid and charcoal. The current work is a step in the production of genetically enhanced dehydration-stress tolerance varieties suitable to new reclaimed area in Egypt.