Table 1. Summary of the effects of high temperature (30 vs. 25°C) or elevated CO2 levels [↑; 970 vs 401 parts per million (ppm)] on viral titers in Nicotiana benthamiana plants infected with Potato virus Y (PVY), Cucumber mosaic virus (CMV), or a Potato virus X (PVX) vector, either unaltered or expressing the CMV 2b protein or the PVY P1-HCPro bicistron.
Viral titers in leaf disks or relative to total protein in leaf disks are indicated as a proportion of the values reached at 25°C or at standard (st; 401 ppm) CO2 levels (arbitrary values of 1), as well as are the symptoms caused to the plants.
| Effect of high temperature (30°C vs. 25°C) | |||
| Virus | viral titer (25°C value = 1) | Symptoms | |
| leaf disk | total protein | ||
| PVY | 0,46 | 0,41 | attenuated |
| CMV | 0,88 | 0,96 | similar |
| PVX | 0,56 | 0,63 | symptomless |
| PVX-P1-6x-HCPro | 0,20 | 0,23 | symptomless |
| PVX-6x-2b-HA | 0,29 | 0,31 | symptomless |
| Effect of ↑ CO2 (970 ppm vs. 401 ppm) | |||
| Virus | viral titer (401 ppm value = 1) | Symptoms | |
| leaf disk | total protein | ||
| PVY | 0,94 | 1,51 | similar |
| CMV | 2,35 | 4,57 | similar |
| PVX | 0,76 | 1,65 | similar |
| PVX-P1-6x-HCPro | 0,87 | 1,64 | similar |
| PVX-6x-2b-HA | 0,72 | 1,48 | similar |