Table 1.
Effects of inoculation with PGPR strains and external application of SA on concentration of main shoot essential oil components of M. × piperita plants (mean ± SE). Means followed by the same letter in a given column are not significantly different according to the Tukey test (p < 0.05).
| Treatments | Linalool (µg/g fw) | (−)-Limonene (µg/g fw) | (−)-Menthone (µg/g fw) |
|---|---|---|---|
| Control | 0.15 ± 0.01 a | 0.20 ± 0.02 a | 0.50 ± 0.03 a |
| G | 0.61 ± 0.07 b | 0.76 ± 0.06 b | 1.15± 0.05 bc |
| S | 0.48 ± 0.08 b | 0.73 ± 0.08 b | 1.34 ± 0.15 c |
| W | 0.52 ± 0.05 b | 0.65 ± 0.07 b | 0.99 ± 0.09 b |
| Control for SA | 0.14 ± 0.02 a | 0.19 ± 0.04 a | 0.43 ± 0.09 a |
| 1 mM SA | 0.54 ± 0.07 b | 1.09 ± 0.18 b | 1.30 ± 0.09 b |
| 2 mM SA | 0.40 ± 0.07 ab | 1.01 ± 0.20 b | 1.40 ± 0.09 b |
| 1 mM SA + G | 0.41 ± 0.03 cd | 0.91 ± 0.06 b | 1.34 ± 0.07 b |
| 1 mM SA + S | 0.32 ± 0.03 ab | 0.99 ± 0.18 b | 1.71 ± 0.35 c |
| 1 mM SA + W | 0.40 ± 0.05 ab | 0.66 ± 0.17 ab | 1.45 ± 0.05 b |
| 2 mM SA + G | 0.34 ± 0.09 ab | 1.14 ± 0.03 b | 1.50 ± 0.22 b |
| 2 mM SA + S | 0.41 ± 0.05 ab | 1.18 ± 0.08 b | 1.53 ± 0.06 b |
| 2 mM SA + W | 0.22 ± 0.06 a | 1.06 ± 0.17 b | 1.31 ± 0.05 b |
G—GB03; S—SJ04; W— WCS417; SA—Salicylic Acid.