Figure 3.
Fluorescence induction kinetics from Mn-deficient leaves of Mn-efficient Vanessa and Mn-inefficient Antonia measured 57 d after planting. The individual phases of the transient are designated O-J-I-P. When Fv/Fm decreased below 0.67 in the Mn-inefficient genotype Antonia, the slope of the transients became negative at two distinct points, 0.2 to 0.4 ms and 75 to 90 ms, and these additional steps were designated as the K and D steps, respectively (notice logarithmic x axis). Inset, A fluorescence transient from a control leaf relative to all of the Mn-deficient (Mn−) measurements shown in the main figure.