Chloroplast ultrastructure in two Crassulacean species and an F1 hybrid with differing biomass δ13C values
Abstract. The chloroplasts of two species of the Crassulaceae and their F1 hybrid were compared by electron microscopy. The two species had contrasting leaf tissue δ13C values of −25°/∞ (Sedum greggii) and −13°/∞ (Cremnophila linguifolia), and the F1 hybrid had a value of − 18°/∞. S. greggii had a mean of 8.9 thylakoids per granum in contrast to C. linguifolia which had a mean of only 3.8 thylakoids per granum. The F1 hybrid had a mean of 6.4 thylakoids per granum. Crystaloids were observed in S. greggii and the hybrid but not in C. linguifolia