TABLE 1.
Gene expression analysis of defense‐related genes in grapevine leaf disks treated with volatile organic compounds and inoculated with Plasmopara viticola
| Gene name | Abbreviation | Treatmenta | |||||
|---|---|---|---|---|---|---|---|
| Control | 2‐pentylfuran | 6‐pentyl‐2H‐pyran‐2‐one | |||||
| Mock | P. viticola | Mock | P. viticola | Mock | P. viticola | ||
| Pathogenesis‐related protein 2 | PR2 | 1.1 ± 0.4a | 6.7 ± 0.9b | 0.9 ± 0.0a | 10.6 ± 1.0c | 5.2 ± 0.4b | 14.4 ± 0.8d |
| Osmotin 1 | OSM1 | 1.0 ± 0.2a | 49.3 ± 9.8b | 7.7 ± 1.4a | 93.1 ± 39.2c | 73.5 ± 13.7b | 199.0 ± 2.3d |
| Osmotin 2 | OSM2 | 1.0 ± 0.2a | 5.9 ± 0.9b | 0.8 ± 0.1a | 7.7 ± 2.4b | 13.2 ± 1.0c | 40.6 ± 3.1d |
| Chitinase 3 | CHIT3 | 1.0 ± 0.1a | 3.1 ± 0.4b | 1.0 ± 0.2a | 5.2 ± 0.6c | 9.2 ± 1.4d | 12.5 ± 0.6e |
| HR‐related gene | HSR | 1.4 ± 0.7a | 400.4 ± 134.7c | 1.4 ± 0.3a | 340.4 ± 96.4c | 55.0 ± 7.7b | 1185.5 ± 84.4d |
Grapevine leaf disks (Vitis vinifera) were treated with water (Control) or with 10 mg L−1 in air volume of 2‐pentylfuran or 6‐pentyl‐2H‐pyran‐2‐one, on a filter paper disk without contact with leaf tissues. Disks were inoculated with Plasmopara viticola or water (Mock) and the respective pure VOC was applied again to the filter paper disk. Leaf disks were collected 6 days post‐inoculation and the relative expression levels (fold change) were calculated respect to mock‐inoculated control leaf disks using actin as constitutive gene for normalization (Perazzolli et al., 2012) and comparable results were obtained with VATP16 gene. Mean and standard error values of three replicates (dishes with five leaf disks each) are presented for each treatment. For each gene, different letters indicate significant differences according to Fisher's test (P ≤ 0.05). Expression profiles were validated by an independent repetition of the experiment.