Figure 4. Cell viability and superoxide radical accumulation in the finger millet transgenic plants expressing mtlD gene under methyl viologen coupled with high light-induced oxidative stress.

Excised leaf segments from T₁ generation finger millet transgenic plants were exposed to oxidative stress as described in material and methods section. At the end of stress, a sub set of leaf segments were incubated in TTC solution and cell viability was calorimetrically estimated by measuring the extent of reduction of TTC into formazan (A). Another sub set of leaf segments were used for superoxide radical estimation during stress. XTT solution was added to the incubation medium and XTT reduction during stress was measured by calorimetric method (B). Each bar represents the mean of standard error values (n = 10). Experiments were repeated twice. Result from one experiment is presented here and results for another independent experiment were similar. Asterisks indicate values are statistically significant (student's t test; p<0.05) versus corresponding wild-type.