Fig. 5
Comparison of different operation protocols for determination of ΦPSII in HT performance. Protocols differ in operating times (stay in FluorCam chamber) as well as in adaptation times (stay in adaptation tunnel). a System for small plants. b System for large plants. c Influence of adaptation and operating time variation on the values of ΦPSII measured at a PAR of 350 µmol m−2 s−1 in different maize accessions (48 DAS). Measurements were carried out successively at one day in periods of 38 or 75 min, respectively (total time 4 h). The data are the mean ± SD of 4–5 replicate measurements. Letters indicate statistically significant differences at the p < 0.05 level according to ANOVA and post-hoc Bonferroni test