2.6.1 Isolation and identification of AM fungal spores
The wet sieving method was used
to obtain spores. The spores were placed under a stereomicroscope for
count and observation. Then transferred spores to polyvinyl
alcohol-lactic acid-glycerol (PVLG) with a pipette, and morphological
characteristics were examined microscopically. It included spore color,
shape, size, sporiferous saccule, spore wall thickness and type,
subtending hyphae width and shape. The spores were identified according
to the photos and feature and feature descriptions from VA
mycorrhizal fungi identification manual (Schenck & Perez, 1990), INVAM
(https://invam.ku.edu/), International AM fungal classification system
(http://www.amf-phylogeny.com/).
AM fungal spore density, species richness, relative abundance (RA),
frequency, importance value (I), and species alpha diversity index were
calculated per 10 g of air-dried soil sample. The degree of AM fungal
dominance was assigned into four categories according to their important
values (I), I > 50% means dominant species, 30%
< I ≤ 50% means subdominant species, 10% < I ≤
30% means accompanying species and I ≤ 10% means rare species.