Effet de l'arbre producteur sur la croissance et la qualité de plants de chêne liège (Quercus suber L.) en pépinière

The objective of this work was to assess the effects of the parental tree of cork oak, which is often associated with acorn size on seedling growth and quality during the nursery stage. The test was conducted in the experimental nursery of the regional station of forest research of Jijel following a completely randomized block resign with three replications. Seeds of the four selected trees were individually sown on WM container type of 400 cm³ filled with Acacia cyanophylla Lindl compost. The following parameters were measured: emergence percentage and speed, height and collar diameter growth, stem and root biomass and root quality.  The results obtained showed that seedling emergence and growth were influenced by the parental tree. The seedlings from large acorns (>6g) were significantly higher than those from small acorns. Seedlings from large acorns (>6g) were significantly higher than those from small acorns. The dry biomass of the stem and root parts were also influenced by the parental tree, the recorded values of the dry biomass were superior in the trees producing large acorns (>6g), with an average of 7.22 g/seedling against 5.91 g/seedling  in plants from small acorn seedling (<5g).  Examination of the quality of the root system showed a low deformation rate of about 11.66%, of which 6.66% represents detrimental deformations (Collar stick) and 5% of non detrimental deformations (Taproot division).