Spore density and root colonization by arbuscularmycorrhizal fungi in Heavy-Metal-Contaminated Soils

Abstract

High concentrations of heavy metals have been shown to adversely affect the size, diversity, and activity ofmicrobial populations in soil. The aim of this work was to determine how the diversity of arbuscularmycorrhizal(AM) fungi is affected by the addition of sewage-amended sludge containing heavy metals in a long-termexperiment. Six AMF ecotypes werefound in the experimental soils, showing consistent differences with regard to their tolerance to the presenceof heavy metals. AMF ecotypes ranged from very sensitive to the presence of metals to relatively tolerant to highrates of heavy metals in soil. Total AMF spore numbers decreased with increasing amounts of heavy metals inthe soil. Mycorrhiza is a mutualistic relationship between plant roots and fungal hyphae. In order tosurvey of percentage root colonization and mycorrhizal spore density in soil, different locations in and around Delhi. Soil samplingwas carried out in June 2012 from surface to 30 cm depth.There was variation in the mycorrhizal colonization and spore number. Therefore,the present study revealed that the genus Glomuswas more predominant than others and Acuolosporawas least amongst therecovered AMF spores.