EFFECT OF SEEDS TREATMENT WITH Trichoderma harzianum ON ARGAN PLANTS GROWTH

The attempts of argan tree (Agrania spinosa (L.) Skeels) reforestation programs, as a multi-use agro-forestry species deal with the mastering the production of superior quality seedlings in nurseries. Trichoderma spp. are well known as soil inhabitant and endophytic plant symbionts that are widely used as seed treatments to enhance plant growth. In the same perspective, the present study aims to highlight the effect of treatments of argan seeds with spores of a Trichoderma harzianum isolate on seed germination and argan seedlings growth. Thus, after 8 months of cultivation in a greenhouse, the root system and aerial parts of the plants derived from the treated seeds presented a significant increase in their fresh weights to reach a respective average value of 5.33 g and 2.43 g, against 1.5 g and 1.03 g in control plants. Also, the average height and number of branches per plant were 26 cm and 0.33 respectively. While, the control plants exhibited an average height of 9.33 cm and did not develop branches. Colonization of roots by T. harzianum was 100%. These results make it possible to envisage the improvement of the technical reforestation route based on argan, with a view to increasing the success rate of ecological regeneration and restoration operations.