MYCORRHIZAL DEPENDENCY OF MICROPROPAGATED ARGAN TREE (ARGANIA-SPINOSA) .2. MINERAL-NUTRITION

The influence of V.A. mycorrhization on mineral nutrition of 2 clones of Argania spinosa was studied with in-vitro micropropagated plantlets grown in confined medium under controlled conditions. Inoculation, wh ich increased dry matter production by a factor of 4.5, also increased P concentration in the plant, especially in the leaves, and the mycor rhizal plants mobilized 15 times more P than control plants. N concent ration was slightly lower in mycorrhizal plants, but total N content w as 3 times higher. Uptake of micro elements was also affected inoculat ion increasing plant Fe, Zn and Cu content. Mineral nutrition in the t est clones seemed affected by root/shoot ratio and other genetically-r elated characteristics, such as Fe translocation efficiency. These res ults help us to understand how its deep mycorrhizal root system might allow Argania spinosa not only to grow in infertile arid areas but als o to improve top-soil fertility by a litter effect.