title: Spatiotemporal variation of arbuscular mycorrhizal fungal colonization in olive (Olea europaea L.) roots across a broad mesic-xeric climatic gradient in North Africa.
abstract: This study aims to determine the spatiotemporal dynamics of root colonization and spore density of arbuscular mycorrhizal fungi (AMF) in the rhizosphere of olive trees (Olea europaea) with different plantation ages and under different climatic areas in Algeria. Soil and root samples were seasonally collected from three olive plantations of different ages. Other samples were carried out in productive olive orchards cultivated under a climatic gradient (desertic, semi-arid, subhumid, and humid). The olive varieties analysed in this study were Blanquette, Rougette, Chemlel and the wild-olive. Spore density, mycorrhization intensity (M%), spore diversity and the most probable number (MPN) were determined. Both the intensity of mycorrhizal colonization and spore density increased with the increase of seasonal precipitation and decreased with the increase of air temperature regardless of the climatic region or olive variety. The variety Rougette had the highest mycorrhizal levels in all plantation ages and climates. Spore community was composed of the genera Rhizophagus, Funneliformis, Glomus, Septoglomus, Gigaspora, Scutellospora and Entrophospora. The genus Glomus, with four species, predominated in all climate regions. Spores of Gigaspora sp. and Scutellospora sp. were the most abundant in desertic plantations. Statistical models indicated a positive relationship between spore density and M% during spring and winter in young seedlings and old plantations. A significant positive relationship was found between MPN and spore density under different climates. For a mycotrophic species, the rhizosphere of olive trees proved to be poor in mycorrhiza in terms of mycorrhizal colonization and numbers of the infective AMF propagules.
authors.affiliation: Laboratoire de Biologie Végétale et Environnement, Department of Biology, Faculty of Sciences, University of Badji Mokhtar, Annaba 23000, Algeria.
authors.forename: Amel
authors.initials: A
authors.lastname: Meddad-Hamza
authors.affiliation: Laboratoire de Biologie Végétale et Environnement, Department of Biology, Faculty of Sciences, University of Badji Mokhtar, Annaba 23000, Algeria.
authors.forename: Nabila
authors.initials: N
authors.lastname: Hamza
authors.affiliation: Department of Natural and Life Sciences, Faculty of Exact Sciences and Natural and Life Sciences, University of Tebessa, Tebessa 12000, Algeria.
authors.forename: Souad
authors.initials: S
authors.lastname: Neffar
authors.affiliation: Laboratoire de Biologie Végétale et Environnement, Department of Biology, Faculty of Sciences, University of Badji Mokhtar, Annaba 23000, Algeria.
authors.forename: Arifa
authors.initials: A
authors.lastname: Beddiar
authors.affiliation: INOCULUMplus Technopôle Agro-Environnement RD31, Bretenière 21110, France.
authors.forename: Silvio
authors.initials: S
authors.lastname: Gianinazzi
authors.affiliation: Department of Natural and Life Sciences, Faculty of Exact Sciences and Natural and Life Sciences, University of Tebessa, Tebessa 12000, Algeria. Electronic address: chenchouni@gmail.com.
authors.forename: Haroun
authors.initials: H
authors.lastname: Chenchouni
mesh_terms: D000352:Africa, Northern; D000462:Algeria; D044822:Biodiversity; D004784:Environmental Monitoring; D055137:Glomeromycota; D038821:Mycorrhizae / Q000145:classification* / Q000254:growth & development; D031658:Olea; D018517:Plant Roots / Q000382:microbiology; D058441:Rhizosphere; D012621:Seasons; D012987:Soil; D012988:Soil Microbiology; D013172:Spores, Fungal
chemical_list: D012987:Soil
keywords: Arbuscular mycorrhizal fungi diversity; North-African climates; Olive varieties; Plantation age; Seasonal dynamics