Contribution à l’étude du potentiel mycorhizogène des sols salins de la région du Douaima (Ain Temouchent)

Abstract

The main objective of this study is to evaluate the mycorrhizogenic potential of saline soils in the Douaima wetland, in the commune of Hammam Bouhajar, Aïn Témouchent province. To achieve this, several physico-chemical and biological indicators were studied : soil texture, pH, electrical conductivity, redox potential, total dissolved solids (TDS), NaCl content, organic matter content, and calcium carbonate dosage. The selected biological indicators are root mycorrhizal colonization, spore density, and mycorrhizal infective potential (MIP). Particular attention was given to the impact of the pioneer halophyte species Salicornia fruticosa on the mycorrhizal dynamics of the rhizospheric soils. The results revealed a relatively low spore density across all soils (238 spores/g in soil 1 and 199 spores/g in soil 2, compared to 182 spores/g in bare soil), probably due to salinity constraints. The mycorrhizal infective potential (MIP) was moderate in the rhizospheric soils (42.13 for soil 1 and 32.40 for soil 2) and very low in bare soil (66.89). On the physico-chemical level, the soils have a silty- clayey texture (soil 1 and bare soil) to silty-sandy (soil 2), a moderate organic matter content (2.04% in soil 1, 4.22% in soil 2, and 2.57% in bare soil), an alkaline pH (7.95 in soil 1, 8.12 in soil 2, and 8.11 in bare soil), and moderate to average electrical conductivity. The obtained results show that, despite the constraints imposed by salinity, the rhizospheric soils associated with Salicornia fruticosa maintain a functional mycorrhizal potential. These observations suggest that this halophyte could contribute to the maintenance of arbuscular mycorrhizal fungi communities in saline environments. Thus, AMF could constitute an interesting lever for restoration and rehabilitation programs of saline soils in coastal wetlands.