Spore density and root colonization by arbuscular mycorrhizal fungi in some species in the northwest of Iran

Mycorrhiza is a mutualistic relationship between plant roots and fungal hyphae. In order to survey of percentage root colonization and mycorrhizal spore density in soil, a region named Kharajoo was selected in vicinity of Maragheh in the northwest of Iran. Soil sampling was carried out in June 2011 from surface to 30 cm depth. Roots and rhizospheric soil of 13 species belonging to 10 families were taken according to their abundance and dominance. Astragalus parrowianus Boiss. and Alopecurus arundinaceus Poir. showed the highest percentage root colonization and the highest number of spores were observed in A. parrowianus, A. arundinaceus and Crepis sancta (L.) Babcock rhizospheres. There was significant relationship between soil physical and chemical factors and number of spores, as well as between these factors and percentage root colonization. Furthermore, there was negative correlation between number of spores with phosphorus content and electric conductivity of soil samples and positive correlation between number of spores and root colonization. All analyses were carried out by SPSS software.