3.3.1 Morphological identification of AM fungi
There were 4461 AM fungal spores isolated from all soil samples, and 9
genera and 20 species were identified morphologically. Among them, 7
species belonging to Acaulospora are the most diverse, accounting
for 35% of the total number of species, followed by the genusGlomus with four species, accounting for 20% of the total number
of species.
The relative abundance (RA) and importance values (I) of AM fungal
spores under the N application treatment were analyzed (Table 4). The
soil samples from the CK had the most abundant spore species, with 17 AM
fungal species identified, whileAcaulospora spinosa and Claroideoglomus lamellosum only
appeared in CK and not found in other treatment.
Gradual reduction of spore
species in soil samples with increasing N addition concentration, and 14
species of AM fungi were isolated and identified in the LN treatment.
There were also 14 species in the MN treatment, in whichSclerocystis sinuosa was unique and never found in other
treatments. It was found that HN treatment reached the least AM fungal
species of 10. In summary, the increasing of N addition concentration
gradually reduced the spore species.