RESULTS
Interactive effects of elevated CO2 and heat stress on
photochemical efficiency, membrane damage and water
potential in leaves of Ailsa and not seedlings
To understand the interactive effects of elevated CO2 and heat
stress in wild-type (Ailsa) and ABA-deficient mutant (not)
tomato plants, some stress indicator parameters, Fv/Fm, EL, MDA and leaf water potential, were studied. Irrespective of
CO2 enrichment, Fv/Fm was remarkably decreased after heat
stress and recovery period in both genotypes (Fig. 1A, B). The
decline in Fv/Fm in response to heat stress was more drastic in
not (55%) than Ailsa (26%) compared with their respective
controls. However, the enrichment of CO2 significantly
increased Fv/Fm over its heat or recovery alone treatment in
both genotypes. Importantly, the effect was more obvious in
not seedlings, where elevated CO2 increased Fv/Fm by 49.5%
and 116.9% at the heat and recovery time points, respectively,
compared with ambient CO2. Again, recovery treatment
increased the Fv/Fm value in the heat-stressed Ailsa seedling
with or without CO2 enrichment. However, recovery treatment
alone decreased (15.5%) and recovery treatment with elevated
CO2 increased (22.6%) the Fv/Fm value in heat-stressed not
seedlings