5. Conclusions
In summary, Chl fluorescence imaging proved to be a useful technique to investigate the plant photosynthetic performance under progressive Fe stress and recovery after Fe resupply. Furthermore, it was shown that the effects of different degrees of Fe stress on strawberry leaves generate spatio-temporal heterogeneity in fluorescence response, pointing out the inadequacy of using single time or single point leaf analyses to monitor Fe deficiency. The results from this study also suggest that II measured in the interveinal tissue could be a better indicator for an early and fast detection of Fe deficiency than Fv/Fm, and could be applied for fertilization management