Characterization of endomycorrhizal fungi and their effect on the health status of olive plants (Olea europea L.) in western Algeria

Abstract

This study concerned the characterization of endomycorrhizal fungi associated to a variety of olive tree which is endemic to Algeria ; the Sigoise variety (Olea europea L.). The study was carried out in western Algeria where the cultivation of this variety is dominant. As methodological approaches, we used techniques that allow to highlight several biological aspects of endomycorrhization. Indeed, the estimation of the natural endomycorrhizal infection in the roots of olive trees was carried out as well as the study of the endomycorrhizal potential of the soil (EMP). Also, an estimation and identification of natural endomycorrhizal fungi of the soil and their effects on the sanitary state (growth) of the olive plants were undertaken in the greenhouse. In results, microscopic examinations of olive tree root fragments revealed a very high mycorrhization rate (more than 80%) with the presence of different structures characteristic of arbuscular endomycorrhizae : arbuscules, vesicles and pellets, independently of the age and season of sampling. Morphological characterization of fungal spores, isolated from rhizospheric soils of olive tree, revealed the presence of three genera belonging to the order of Glomales: Glomus sp., Acaulospora sp. and Gigaspora sp. with a predominance of Glomus. Moreover, the growth parameters of the aerial and underground parts of the olive plants were positively affected after inoculation, which reflects a good sanitary condition of the plants. In conclusion, our work provided additional knowledge on the controlled mycorrhization of olive plants and opened interesting perspectives for the application of this biotechnology to the production of olive plants in greenhouses.