3.4 AM fungi and soil properties
Fungicide (benomyl) addition
significantly reduced mycorrhizal
root colonisation across all plots from 2019 to 2020 (Fig. 4).
Furthermore, P input alone significantly reduced mycorrhizal root
colonisation in comparison with the control over two years (Fig. 5).
Besides, we found that fungicide (benomyl) addition had minimal
influence on soil available P and inorganic N in either 2019 or 2020 in
our study (Fig. S2; all p > 0.05). In 2020, N input
alone enhanced soil inorganic N by 121.17% compared
with
control plots (Fig. S3a and b; F 1, 28 = 93.44,p < 0.01). Moreover, P input alone enhanced soil
available P in the soil by over 10 times (2019) and 14 times (2020)
relative to control plots (Fig. S3c and d; F 1, 28= 81.26, p < 0.01, F 1, 40 =
191.68, p < 0.01, respectively). Mycorrhizal
suppression and P input alone greatly decreased AM fungal neutral lipid
fatty acid concentrations in 2019 and 2020 (Fig. S4a and b, Table S4)
but did not change those of other microbial groups (Table S4, allp > 0.05).