Typesetter to place Figure 4 here
Chl a fluorescence induction transient: For these
measurements, OJIP curves were recorded up to 2 s, after excitation with
650 nm light of high intensity (3500 µmol photons m-2s-1), as provided by an array of 3 LEDs.Figure 4a shows Chl a fluorescence transients of
dark-adapted leaves of Arabidopsis thaliana , plotted on a
logarithmic time scale from 20 μs to 2 s; here, all the curves were
normalized at Fo. Fluorescence transients of both VC and transgenic
plants show typical OJIP curves. The transgenic CAx3 and CAx5 have a
similar fluorescence rise from O to J, but a faster rise from J to I and
I to P as compared to those in the VC.
To study further differences between the transgenics and the controls,
the IP rise was normalized, both at the I level (30 ms) as well as at
the P level (290 ms) (see Fig. 4b ). The normalized I-P curves
clearly reveal that the transgenic plants had faster IP rise than the
VC. Further, when the OJIP curves were normalized at I only, we
observe a faster IP rise in the transgenics than in the vector controls
(Fig. 4c ).