Biotechnologie et biomatériaux

Abstrait

Effect of Moroccan phosphate sludge-compost associated with arbuscular mycorrhizas and phosphate solubilizing bacteria on growth and development of tomato

Sanae El Maaloum, Zainab El Alaoui-Talibi, Abdelkarim Fılalı-Maltouf, Allal Douıra, Saad Ibnsouda-Koraıchı, Soumia Amır andCherkaoui El Modafar

The exploitation of phosphate mines generates an important quantity of phosphate sludge that remains accumulated and not valorized. The
phosphate containing in sludge is present in complexed form that have low solubility, therefore, a very low agronomic efficiency. Hence, it is
important to develop ecological and economic techniques to deal with phosphorus solubility and availability problem. Faced with this problem,
composting with organic matter and rhizosphere microorganisms offers an interesting alternative and more sustainable for agriculture. The objective in this work is to study the interaction of Arbuscular mycorrhizal fungi (AMF), phosphate-solubilizing bacteria (PSB) and phospho-compost (PC) constituted by organic residues and phosphate sludge on the chemical and biological properties of the rhizospheric soil of the treatments studied and on the growth and yield of tomato plants using the poor soil in available phosphorus. The strains of PSB and the species of AMF used in this study are isolated from the plant rhizosphere that grow in phosphate sludge deposits of 2000 and 1998 in Khouribga phosphate mines (Morocco). Combination of soil and phospho-compost, inoculated with PSB, AMF, or with PSB +AMF and the control were used. The results showed that the combination of phospho-compost, PSB and AMF led to very high yields of dry and fresh matter on days 20, 40 and 60 compared to other treatments. The mycorrhizal colonization of roots and available phosphorus concentration in the rhizosphere were increased with time. Alkaline phosphatase activity was higher in PC+ AMF and PC+ PSB+ AMF compared with the control. The combination of phospho-compost, PSB and AMF results in a synergetic or positive action on tomato growth.