Seeds of Sesamum indicum L. were subjected to He-Ne laser radiation with wavelength (λ) 632.8 nm, power intensity 3 mW.cm-2 for different time periods (0, 1, 3, 10, 30, 60, 180, 600 and 1200 seconds). Artificial sun-light treatments (lamp Model 400 W/ 220 v/ 60 hz. China) and integrated white light treatments (400- 760 nm, 3 mW. cm-2) were employed in parallel experiments for the same time periods to compare the effect of different radiations on seed germination and growth parameters. Seed germination percentage was significantly increased in response to laser radiation pretreatment. Meanwhile, the shoot and root length, leaf area and biomass (fresh and dry weights) were significantly improved. Pretreatment of sesame seeds with He-Ne-laser for 120, 300 and 600 sec. were the most effective dose.
Keywords: He-Ne- laser; sesame; germination percentage; growth parameters.
