TY - JOUR AU - Kheloufi, Abdenour AU - Mansouri, Lahouaria AU - Aziz, Nada AU - Sahnoune, Meriem AU - Boukemiche, Sarra AU - Ababsa, Boutheina PY - 2018/07/10 Y2 - 2024/03/28 TI - Breaking seed coat dormancy of six tree species JF - REFORESTA JA - REFOR VL - 0 IS - 5 SE - Articles DO - 10.21750/REFOR.5.02.48 UR - https://journal.reforestationchallenges.org/index.php/REFOR/article/view/78 SP - 4-14 AB - <p>Breaking physical dormancy in some forest seeds is a challenge for scientists and forest managers to obtain an homogeneous germination for larger seed samples. The role played by the seed coat in seed dormancy of six trees with great interest in agroforestry (<em>Robinia pseudoacacia</em>, <em>Leucaena leucocephala</em>, <em>Erythrostemon gilliesii</em>, <em>Styphnolobium japonicum</em>, <em>Acacia dealbata </em>and <em>Brachychiton populneus</em>) was tested by the effects of the pretreatment and its duration on the performance of seed germination, by considering the final germination percentage (FGP) and the mean germination time (MGT). These parameters are estimated at various times of incubation (5, 10 and 15 days) in Petri dishes and stored in darkness at (25 ± 2°C). The pretreatment consists of an immersion of seeds in concentrated sulphuric acid during 30, 60 and 90 minutes.</p><p>Sowing without pretreatment (control) revealed no germination induction for <em>B. populneus</em> and <em>A. dealbata</em>, except for <em>R. pseudoacacia</em>, <em>L. leucocephala</em> and <em>S. japonica</em> where the germination does not exceed 12% for all the experience duration. Generally, pretreatments were very useful to improve seed germination. The time of immersion into sulphuric acid significantly affected (<em>P</em> &lt; 0.0001) the FGP and the MGT in all studied species. A duration of 30 minutes of soaking was adequate to give a very high rate of germination for <em>L. leucocephala</em>, <em>E. gilliesii</em>, <em>S. japonica</em> and <em>A. dealbata</em> with respective FGP of 100%, 95%, 100% and 100%. However, an extended duration of pretreatment of 60 minutes was necessary for a maximal germination for <em>R. pseudoacacia</em> and <em>B. populneus</em> with FGP of 85% and 100%, respectively. A prolonged duration of 90 minutes of presowing was very fatal for <em>L</em>.<em> leucocephala</em>, <em>A. dealbata</em> and <em>B. populneus</em>. An excellent germinative strength is characterized by a higher FGP and a reduced MGT.</p> ER -