a taxonomic overview of the genus anticharis (scrophulariaceae) especially in namibia and angola is presented. three new species are described, viz. a. namibensis b. nord., a. kaokoensis b. nord. and a. angolensis b. nord. a key to the anticharis species of namibia and angola is presented. some aspects of phytogeography, molecular phylogeny and photosynthetic pathways (c3-c4) are briefly discus...

Glycine decarboxylase (GDC) plays an important role in the photorespiratory metabolism of plants. GDC is composed of four subunits (P, H, L, and T) with the P-subunit (GLDP) serving as the actual decarboxylating unit. In C3 plants, GDC can be found in all photosynthetic cells, whereas in leaves of C3-C4 intermediate and C4 species its occurrence is restricted to bundle-sheath cells. The specifi...

PREMISE OF THE STUDY Portulacaceae is a family with a remarkable diversity in photosynthetic pathways. This lineage not only has species with different C4 biochemistry (NADP-ME and NAD-ME types) and C3-C4 intermediacy, but also displays different leaf anatomical configurations. Here we addressed the evolutionary history of leaf anatomy and photosynthetic pathways in Portulacaceae. METHODS Pho...

The scarcity of C4 plants in cool climates is usually attributed to their lower photosynthetic efficiency than C3 species at low temperatures. However, a lower freezing resistance may also decrease the competitive advantage of C4 plants by reducing canopy duration, especially in continental steppe grasslands, where a short, hot growing season is bracketed by frost events. This paper reports an ...

Four species of the genus Flaveria, namely F. anomala, F. liaris, F. pubescens, and F. ramosissima, were identified as intermediate C3-C4 plants based on leaf anatomy, photosynthetic CO2 compensation point, 02 inhibition of photosynthesis, and activities of C4 enzymes. F. anomala and F. rawosissina exhibit a distinct Kranz-like leaf anatomy, similar to that of the C4 species F. trinervia while ...

Grasses with the C3 photosynthetic pathway are commonly considered to be more nutritious host plants than C4 grasses, but the nutritional quality of C3 grasses is also more greatly impacted by elevated atmospheric CO2 than is that of C4 grasses; C3 grasses produce greater amounts of nonstructural carbohydrates and have greater declines in their nitrogen content than do C4 grasses under elevated...