Abstract

Two experiments were conducted during 2016 in the laboratory of the Faculty of Education – Aden, Aden University to study the effect of four different concentrations of the licorice extract, viz., 0, 5, 10 and 15%, on the germination and growth of seedlings of Onion cv. Bafatiem. The first experiment the seeds were soaked for 24 hours in various concentrations of aqueous extract of licorice were planted in plastic dishes and distilled water was added. The second experiment was planted 20 Onion seeds were planted in plastic dishes then treated by aqueous extract of licorice. Two experiments were conducted in complete randomized design with three replicates. Results showed that the seeds soaked in concentration of 5% of licorice extract were improved in germination percentage reached 83.3% comparing with all other treatments, the germination percentage was significantly with control and 10%. The control was increased in fastness germination which reached 3.89 day/seed, caused a significant increase in velocity of seeds germination comparing with all the concentrations of the licorice root extract. The seeds which soaked in a concentration of 5% was homogeny, and reached 23.33 seed/day, this value was a significant comparing with concentrations of 10%, 15% and control. Soaked seeds or direct added to the dishes of licorice extract in the concentrations decreased radical length comparing with control, while soaked seeds at 5% increased plumule length which reached 4.8 cm long, with significant differences comparing with 10% and control. The direct added of licorice extract to the dishes caused inhibition in germination percentage in all concentrations. The control caused a significant increase in germination comparing with all concentrations. Concentration of 15% caused increase in velocity of seeds germination reached 4.28 day/seed. The low concentrations caused increase in homogeny of seeds germination, the control was more homogeny, reached 21.93 seed/day. Length of plumule influence at direct added of licorice extract and caused a significant decrease at all concentrations comparing with the control which gave 6.81 cm long.