Identification of Arbuscular Mycorrhizal Fungi Coexist with Plant Species in Different Habitats of Iranian Oak (Quercus brantii Lindl.) in Ilam

Arbuscular mycorrhizal fungi constitute an important component of soil microflora and coexist with 80% of plant species. The present study was conducted with the aim of Morphology identifying arbuscular mycorrhizal fungi in three habitats (Shanachir, Ilam and Malekshahi) with different climatic conditions and in two aspect slopes, north and south, in the Oak forests of Ilam province.

In order to take soil samples, in each habitat   and both north and south aspect slopes 20 mixed soil samples were taken. A total of 60 samples was taken from all three habitats based on a completely random sampling plan from a depth of 0-20 cm in the spring season. Spore extraction of mycorrhizal fungi was done using the method of sieving and centrifugation with sucrose, and the identification of fungi was done based on the measurement of morphological characteristics and using the identification key and reliable internet sites. The abundance percentage of fungal species was also calculated using the percentage of spores belonging to a fungal species. Venn diagram was used to determine the similarity percentage of fungal species in different habitats and aspect slopes in each habitat.

The results of this study showed that a total of 39 species of arbuscular mycorrhizal fungi belonging to 11 genera were identified in three studied areas and two aspect slopes. 36 fungal species belonging to 11 genera were identified in Ilam habitat, 37 mycorrhizal fungal species belonging to 11 genera Malekshahi and 34 fungal species belonging to 10 genera were identified in Shanachir. The highest percentage of the relative frequency of the fungus genus also belonged to the two genera Acaulospora and Glomus.In all habitats and aspect slopes, the two species Glomus nanolumen and Acaulospora lacunosa had the highest percentage of fungal species abundance. The results of species similarity in different habitats showed that 30 species of mycorrhizal fungi, equivalent to 76.92% of the species, were common among the habitats, and there was one endemic species (Glomus macrocarpum) in Malekshahi city. The results showed that there was a significant difference in the spore density in the study areas (p=0.000), which was higher in Malekshahi and Shenchir than in Ilam. The average spore density was higher in all habitats in the southern aspect slope than in the northern aspect slope. The average density of spores in different areas varied from 111.20 in Ilam to 140.25 in Malekshahi and among different aspect slopes from 105.60 in the north of Ilam to 150.90 in the south of Malekshahi.

The result of the present study showed that mycorrhizal fungi in different areas and aspect slopes were different in terms of the number of fungal species, distribution and number of spores and the highest spore density was observed in the southern aspect slope and in Malekshahi region.