Studies on anatomical characters indicating C3 and C4 photosynthetic metabolism in the genus Boerhavia L. (Nyctaginaceae)

Studies on anatomical characters indicating C3 and C4 photosynthetic metabolism in the genus Boerhavia L. (Nyctaginaceae)

The C3 and C4 photosynthetic pathways in dicotyledons were investigated with the four species of Boerhavia occurring in Nigeria using light microscopy. The study is not yet well reported on dicotyledons as done for monocotyledons. The features cross-examined were stomata index, stomata size, inter-stomatal distance, stomatal density, interveinal distance, intercellular air spaces, leaf thickness, mesophyll thickness, Kranz tissue, one cell distant count criterion, maximum lateral cell count criterion, vein density and vein distance. Based on these features, these species (B. erecta, B. coccinea and B. repens) were grouped into C4 while B. diffusa was grouped as a C3 plant. In particular, interveinal distance less than 166μm and maximum lateral count ranging 2 to 6 will help in grouping C4 dicotyledons species while those that were greater than these values are useful in grouping C3 and plants.