Soil samples containing AMF communities under S. canadensis (SC-A-AMF) and K. striata (KS-A-AMF) from the end of experiment 1 were used as inocula.
For K. striata, however, shoot biomass (Fig. 3A) and shoot 15N (Fig. 3B) decreased (P<0.05) under the SC-A-AMF treatment but increased (P<0.05) under the KS-A-AMF treatment relative to the I-AMF treatment.
The biomass ratio of K. striata to S. canadensis was reduced by SC-A-AMF treatment (P<0.05), but was enhanced by the KS-A-AMF treatment (P<0.05) (Fig. 4A).
Aggressivity index was enhanced by the KS-A-AMF treatment (P>0.05), but was reduced by the SC-A-AMF treatment (P<0.05) (Fig. 4B) relative to the I-AMF treatment.
We designed non-AMF control treatments (I-N-AMF, SC-N-AMF and KS-N-AMF) corresponding to AMF treatments (I-AMF, SC-A-AMF and KS-A-AMF) during the whole study.
Compared to the I-AMF treatment, the SC-A-AMF treatment enhanced (P<0.05) but the K. striata-altered AM fungal community (KS-A-AMF) treatment did not change (P>0.05) the shoot biomass (Fig. 3A) and shoot 15N (Fig. 3B) of S. canadensis.
For treatment SC-A-AMF and its corresponding control (SC-N-AMF), and for treatment KS-A-AMF and its corresponding control (KS-N-AMF), 100 g of soil containing AMF inocula from the end of experiment 1 was incorporated into the soil of each HOST compartment.
The AMF communities and their corresponding non-AMF controls were: the initial non-AMF control (I-N-AMF) and the initial AMF community (I-AMF); the S. canadensis-altered non-AMF control soil (SC-N-AMF) and the S. canadensis-altered AM fungal community (SC-A-AMF); and the K. striata-altered non-AMF soil control (KS-N-AM) and the K. striata-altered AM fungal community (KS-A-AMF).
The S. canadensis-altered AM fungal community (SC-A-AMF) treatment reduced the relative abundance of DNA of G. mosseae but increased that of G. geosporum in roots of K. striata compared to the initial AMF community (I-AMF) treatment with both monoculture and mixed plantings (Fig. 2).
Culture types (monoculture and mixture) did not affect the relative DNA abundance of G. mosseae in roots of native K. striata grown in treatments of I-AMF (F1,6 = 0.58, P = 0.391) and SC-A-AMF (F1,6 = 2.12, P = 0.196) (Fig. 2A).
For G. geosporum, culture types did not change the relative abundance of DNA in roots of K. striata under treatment of I-AMF (_F1,6 = 1.92, P = 0.238), but mixture reduced the relative abundance of DNA in roots of K. striata under the treatment of SC-A-AMF compared to monoculture (F1,6 = 250.89, P = 0.000) (Fig. 2B).
