Negin Moein, Rayhaneh Amooaghaie,
Volume 12, Issue 2 (3-2026)
Abstract
Objective: This research aimed to investigate the effect of treatments such as seed scarification and nitrogenous compounds on seed dormancy breaking, germination indices, and seedling growth of Astragalus adscendens Boiss. & Hausskn.
Method: In the first experiment of this study, the effect of soaking seeds in 95°C boiling water for 5, 10, and 20 minutes, as well as scarification with a razor, on seed germination was investigated based on a completely randomized design. In the second experiment, the effect of scarification with a 50% solution of various chemical compounds (water, hydrochloric acid, sulfuric acid, acetic acid, and hydrogen peroxide) for different durations (2, 5, and 10 minutes) on seed dormancy breaking was evaluated. In the third experiment, the interactive effect of seed scarification with a razor or sulfuric acid and various nitrogenous compounds on seed dormancy breaking and seedling growth of A. adscendens was investigated.
Results: The results of the first and second experiments showed that intact control seeds had only about 20% germination, but 10 minutes of treatment with boiling water and razor scarification increased germination to 60.57% and 70%, respectively. The best values for mean daily germination, peak value, and germination value were obtained with 5 minutes of sulfuric acid treatment, followed by 5 minutes in hydrochloric acid. The results of the third experiment showed that treatment with thiourea, potassium nitrate, and sodium nitroprusside had no significant effect on the germination of intact A. adscendens seeds, but significantly increased the percentage and rate of germination of seeds scarified with a razor or sulfuric acid, as well as the root and shoot length of seedlings. The greatest effect on germination percentage was achieved with the application of sodium nitroprusside (as a nitric oxide-producing compound) on seeds scarified with a razor (90%) or sulfuric acid (79%). Also, potassium nitrate caused the greatest increase in the root length of seedlings from seeds scarified with a razor or sulfuric acid, and the highest shoot length was obtained with the application of sodium nitroprusside.
Conclusion: The obtained results indicate that A. adscendens seeds have both physical and physiological dormancy, and scarification with a razor followed by treatment with sodium nitroprusside is suitable for breaking this dual dormancy.
Highlights
- Sulfuric acid or razor scarification breaks physical dormancy more effectively than boiling water in A. adscendens.
- For the first time, scarification + nitrogenous compounds overcame combined dormancy in A. adscendens.
- Razor scarification followed by sodium nitroprusside was the most effective treatment.
