Physiological, anatomical and biochemical characterisation of photosynthetic types in genus Cleome (Cleomaceae)

摘要: C4 photosynthesis has evolved many times in 18 different families of land plants with great variation leaf anatomy, ranging from various forms Kranz anatomy to occurring within a single type photosynthetic cell. There been little research on typing the family Cleomaceae, which only one species identified, Cleome gynandra L. is recent interest selecting and developing Cleomaceae as model system, since it most closely related Arabidopsis, C3 system (Brown et al. 2005). From screening more than 230 samples species, based measure carbon isotope composition (δ13C) leaves, we have identified two additional C. angustifolia Forssk. (Africa) oxalidea F.Muell. (Australia). Several other δ13C values around –17‰ –19‰, suggesting they are C4-like or intermediate species. Eight were selected for physiological, anatomical biochemical analyses. These included gynandra, NAD–malic enzyme (NAD–ME) paradoxa R.Br., C3–C4 6 others characterised features low CO2 compensation point (Γ), values, Kranz-type bundle sheath (BS) ultrastructure, presence pathway enzymes, selective immunolocalisation Rubisco phosphoenolpyruvate carboxylase. was its Γ (27.5 μmol mol–1), ultrastructural localisation glycine decarboxylase photorespiratory mitochondria BS cells. The six Γ, non-Kranz levels enzymes (very absent) typical plants. results indicate that this an interesting studying genetic basis evolution