Pot Trial Experiment for Endophytic B. safensis ZY16 in C. virgata Sw.

A pot trial assay (with and without B. safensis ZY16 inoculation) was designed, with six replicates for each condition. Each pot contained four plantlets (C. virgata Sw.). The oil-contaminated salinized soil applied in this pot trial assay was prepared by the addition of crude oil and NaCl, with final TPH and salt contents of 10462 mg/kg and 0.51%, respectively. Colonization of the tested endophyte in the plantlets was assessed as described previously (Wu et al., 2018). After 120 days, the plants were harvested, and plant biomasses (dry weights) from two treatments were measured. In addition, petroleum residues were extracted from soils using dichloromethane, and the residual petroleum was measured gravimetrically. Student’s t-test was applied to compare the means of the two treatments at a 0.01 significance level.