The submergence-tolerant species Rumex palustris (Sm.) responds to complete submergence by an increase in petiole angle with the horizontal. This hyponastic growth, in combination with stimulated elongation of the petiole, can bring the leaf tips above the water surface, thus restoring gas exchange and enabling survival. Using a computerized digital camera set-up the kinetics of this hyponastic...

A long-standing controversy exists regarding the laryngoscopic features associated with unilateral denervation of the external superior laryngeal nerve (ESLN). Recently, we modeled acute unilateral cricothyroid muscle paralysis by blocking the ipsilateral ESLN with lidocaine hydrochloride, and identified epiglottic petiole deviation to the side of paralysis during high-pitched voice production ...

The Trachycarpus fortunei palm is a good example of a palm with a large leaf blade supported by a correspondingly large petiole. The way in which the material and functional properties of the petiole interact is analysed using engineering and botanical methods with a view to understanding how the petiole functions from a structural standpoint. Initially, the histological aspects of the petiole ...

Essentially chlorophyll-free mitochondria from photosynthetic (leaf) and non-photosynthetic tissue (petiole) were isolated from spinach (Spinacia oleracea). Leaf mitochondria were found to contain more phosphatidylcholine than phosphatidylethanolamine compared with petiole mitochondria. Galactolipids were found in small and equal amounts (5 mol of galactolipids/100 mol of galactolipids and phos...

BACKGROUND AND AIMS Complete submergence is an important stress factor for many terrestrial plants, and a limited number of species have evolved mechanisms to deal with these conditions. Rumex palustris is one such species and manages to outgrow the water, and thus restore contact with the atmosphere, through upward leaf growth (hyponasty) followed by strongly enhanced petiole elongation. These...

The paper deals with pharmacognosy of Centella asiatica (L.) Urban, including its morphological, anatomical, chemical constituents and powder analysis. Stomata are mostly anisotricytic, isotricytic and few tetracytic. Sphaero-crystals of calcium oxalate are observed in palisade, spongy and ground parenchyma of leaf lamina, petiole and rhizome and absent in roots. Uniseriate flagellate conical h...

The impact of water deficit on stomatal conductance (g(s)), petiole hydraulic conductance (K(petiole)), and vulnerability to cavitation (PLC, percentage loss of hydraulic conductivity) in leaf petioles has been observed on field-grown vines (Vitis vinifera L. cv. Chasselas). Petioles were highly vulnerable to cavitation, with a 50% loss of hydraulic conductivity at a stem xylem water potential ...

Diel variation in specific hydraulic conductivity ( k s ) was recorded in petioles of two savanna tree species, Schefflera macrocarpa and Caryocar brasiliense , from central Brazil. These two species have compound leaves with long petioles (10–30 cm). In both species, petiole k s decreased sharply with increasing transpiration rates and declining leaf water potentials ( y L ) during the morning...

We present the leaf anatomy of seven amphibious species of Aeschynomene L. (Papilionoideae, Leguminosae), interpreting their structures and ecological functions, and also, providing information on which their taxonomy can be based, especially of morphologically similar species. We evaluated Aeschynomene americana, A. ciliata, A. evenia, A. denticulata, A. fluminensis, A. rudis and A. sensitiva....

In formicine ants, the hair fields associated with the neck and the petiole (alitrunk-petiole and petiole-gaster joints) have long been established to function in graviception. Here, we examine a possible role of these hair receptors in three-dimensional (3-D) path integration of the (formicine) desert ant, Cataglyphis fortis. Cataglyphis judge the ground distance when travelling over hills, al...