Fig. 2. The effect of sequential application of high temperature treatments (HTTs) (4 d at 35°C) on maize endosperm nuclei number (2A) and mitotic index (2B). Nuclei number was determined by flow cytometry (FCM). Different letters indicate a significant difference of means, n = 6, LSD = 0.05. Mitotic index was determined as the number of nuclei in prophase, metaphase, anaphase, and telophase, divided by the total number of nuclei viewed. Different letters indicate a significant difference of means, n = 6 endosperms, and 300 nuclei per endosperm were counted, LSD = 0.05.