The present study was conducted to evaluate various chemical scarification methods for breaking physical dormancy of Crotalaria senegalensis seeds. The seeds were subjected to the following treatments: (1) soaking in hot distilled water (80°C) for 15 and 30 min, (2) immersion in H2SO4 (98%) for 20, 25 and 30 min, (3) immersion in 0.5 %, 1% and 1.5 % KNO3 and (4) soaking in 50, 100 and 150 µM H2O2. All scarification treatments improved the germination capacity of C. senegalensis seeds, the

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... t final germination rate and germinate rate index, were recorded after soaking in 150 µM H2O2, followed by soaking intact seeds in H2SO4 (98%) for 30 min. and immersion seeds in 1.5 % KNO3. The results showed that using concentrated H2SO4 (98%) for 30 min to break seed physical dormancy of C. senegalensis was the second most effective treatments ( after 150 µM H2O2 treatment) but it is commonly not preferred due to its cost, safety risk and environmental precautions involved. In conclusion, to break both physical and/or physiological dormancy of C. senegalensis seeds, soaking in 150 µM H2O2 and 1.5 % KNO3 represent the most recommended treatments.