Effects of acacia (Acacia auriculaeformis A. Cunn)-associated fungi on mustard (Brassica juncea (L.) Coss. var. foliosa Bailey) growth in Cd- and Ni-contaminated soils.

To evaluate the effect of Acacia auriculaeformis-associated fungi on the growth of mustard [Brassica juncea (L.) Coss. var. foliosa Bailey] in Cd- and Ni-contaminated soils and design novel plant-fungi associations for bioremediation purpose. Endophytic Trichoderma H8 and rhizosphere Aspergillus G16 were applied for rhizoremediation of Cd-, Ni-, and Cd-Ni combination-contaminated soils through association with B. juncea (L.) Coss. var. foliosa. Compared with the noninoculated control plants, inoculation with Trichoderma H8 produced 109%, 41% and 167% more fresh weight (FW) plant yields in the Cd-, Ni-, and Cd-Ni-contaminated soils, respectively (P < 0.05). Similarly, plants inoculated with Aspergillus G16 produced 109%, 47% and 44% more FW plant yields in these contaminated soils, respectively. Plants co-inoculated with these two strains produced 118%, 100% and 178% more FW plant yields, respectively. The inoculations also increased the translocation factors and metal bioconcentration factors. The efficiency of phytoextraction for B. juncea (L.) Coss. var. foliosa was enhanced after inoculating with Acacia-associated fungi. The use of plant-fungi association may be a promising strategy to remediate metal-contaminated soils.