LAUSR

The effect of textural and physicochemical characteristics of five cedar forest soils on 4- and 8-month-old seedlings of Cedrus atlantica Manetti was studied in a controlled growth chamber. During their growth, cedar seedlings show a change in the root architecture by the levels of Corg, N, P, and by the soil granulometry. The Tioumlilin soil conditions stimulate mainly the cumulative length and the number of secondary roots. However, the cedar forest soil of Tazekka predominates over most soils in its effect on growth by the balance of chemical elements and the high percentage of coarse particles. The analysis of the densities of secondary and tertiary roots and the cumulative length of secondary roots show four different root architectural development strategies of C. atlantica seedlings which may justify the low level of mycorrhization on young seedlings in the natural cedar forest soil. The variations of the root architectural parameters of C. atlantica seedlings are discussed in relation to the characteristics of cedar forest soils.