UNLABELLED Pelargonium L. genra (Fam. Geraniaceae) includes over 250 species, most of it native to southern Africa. Nowadays, four perennial species are cultivated in Romania as ornamental plants. Our aim was to establish the main characteristics and differences that occur between Pelargonium zonale, P. hispidum, P. grandiflorum, P. peltatum and P. radens. All in all, the quantitative differenc...

(Leaf anatomy of Araucaria angustifolia (Bertol.) Kuntze (Araucariaceae)). Immature and mature leaves of juvenile and adult plants of Araucaria angustifolia (Araucariaceae) were observed with the objective of updating the morphoanatomical data of the leaves of this species, which were restricted to basic descriptions in previous studies. The observations, made in optical allowed to establish an...

Guzmania lingulata (L.) Mez. ‘Cherry’ plants were grown in coconut husk chips. All plants were given 8 mM nitrogen (N), 2 mM phosphorus (P), 4 mM calcium (Ca), and 1 mM magnesium (Mg) at each irrigation with potassium (K) concentration at 0, 2, 4, or 6 mM. After 9 months, K concentration did not alter the number of new leaves, and shoot and root dry weights. Increasing K concentration did not a...

In the mesophyll of Teucrium polium L. leaves, isolated or grouped idioblastic secretory cells occur in contact with the distal (adaxial) vessel elements of the vascular bundles. They appear to originate from one or more bundle sheath cells and their intracellular space is entirely occupied by the secretory material. The latter has a glycoproteinaceous constitution (mucilage), as histochemical ...

One of the most tantalizing unresolved questions in plant hydraulics is: where does water evaporate within the leaf? While several studies have explored experimental routes to answer this question (e.g. Sheriff & Meidner 1974; Farquhar & Raschke 1978), none have been able to provide a clear answer. In this issue of Plant, Cell & Environment, Tom Buckley has presented a new mathematical model in...

This paper proposes a new interpretation for primary thickening in monocotyledons. The anatomy of the vegetative organs of the following species was examined: Cephalostemon riedelianus (Rapataceae), Cyperus papyrus (Cyperaceae), Lagenocarpus rigidus, L. junciformis (Cyperaceae), Echinodorus paniculatus (Alismataceae) and Zingiber officinale (Zingiberaceae). The endodermis with meristematic acti...

Strong positive correlations between the maximum rate of canopy photosynthesis, canopy-averaged foliar nitrogen concentration, and canopy albedo have been shown in previous studies. While leaf-level relationships between photosynthetic capacity and foliar nitrogen are well documented, it is not clear whether leaf-level relationships between solarweighted reflectance and nitrogen underlie the ca...