| المستخلص: |
Acacia saligna is grown widely along the Mediterranean coast of Libya where it is used both for erosion prevention and as forage for a range of species. The main problem encountered using Acacia species as forage for range programmes is the poor seed germination and seedling establishment. Experiments were carried to investigate the effect of dormancy breaking treatments and sowing depth on germination and seedling establishment of A. saligna, comparing large (8x3 mm), medium (5 x 2.5 mm) and small (3x2 mm) seeds. For dormancy breaking, Seeds were treated by pouring 200 ml of boiling water onto 400 seeds and leaving them to cool. Boiling water was applied one, two, three or four times at 30 min intervals. Final germination was determined in a Petri dish germination test and establishment assessed after sowing at 30 mm depth in sandy soil in pots in a greenhouse. In a second greenhouse experiment, dormancy of seeds of each of the size classes was broken by three applications of boiling water at 30 min intervals. Thereafter, imbibed seeds of each size class were sown at 10, 20, 30 or 40 mm depth. Seedling establishment was assessed after 7 weeks as well as the shoot and root lengths and dry weights of surviving seedlings. Treatment of A. saligna seeds of all sizes with boiling water three times gave the greatest seed germination. Large seeds germination earlier and achieved greater germination than smaller seeds, and greater seedling establishment from 30 mm depth sowing with all boiling water treatments. No or very few seeds emerged and survived from 40 mm depth. Sowing A. saligna seeds at 30 mm depth generally gave the greatest seedling growth from large and medium seeds whereas 20 mm was more suitable for small seeds. These results may be useful as a guide for carrying out some nursery operation, regarding Acacia species and cold enable avoiding the most complex hazard one. \
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