A pressure chamber was used to measure matric potentials of frozen and thawed leaves. Significant matric potentials were demonstrated in sunflower (Helianthus annuus L.), yew (Taxus cuspidata Sieb. and Zucc.), and rhododendron (Rhododendron roseum Rehd.). Matric potentials were particularly negative in rhododendron and were correlated with the amount of cell wall present and with the volume of ...

We prove that a codimension one foliation of an orientable paracompact manifold has at most a countable number of nonorientable leaves. We also give an example of a codimension one foliation of a compact orientable manifold with an infinite number of nonorientable leaves. Introduction. The purpose of this paper is to investigate the occurrence of nonorientable leaves in a codimension one foliat...

Starch mobilization is well understood in cereal endosperms, but both the pathway and the regulation of the process are poorly characterized in other types of plant organs. Arabidopsis leaves offer the opportunity for rapid progress in this area, because of the genomic resources available in this species and the ease with which starch synthesis and degradation can be monitored and manipulated. ...

Background & Aim: Applications of synthetic antioxidant in food have side effects. In present study, the antioxidant potential of Morus alba leaves, as natural antioxidant, was screened with cupric ion reducing assay (CUPRAC assay) and inhibition of lipid peroxidation. The aim of this study was to determine the total antioxidant activity of Morus alba leaves. Martial & Method...

Starch is the most abundant storage carbohydrate produced in plants. The initiation of transitory starch synthesis and degradation in plastids depends mainly on diurnal cycle, post-translational regulation of enzyme activity and starch phosphorylation. For the proper structure of starch granule the activities of all starch synthase isoenzymes, branching enzymes and debranching enzymes are neede...

Leaves exhibit a wide range of form and function: as well as the flattened photosynthetic organs we are most familiar with, modifications of leaf morphology produce the rigid spines of cacti, the cup-shaped insect traps of pitcher plants, colorful flower parts such as petals and some of the tendrils used for attachment by climbing plants. One fundamental choice in leaf architecture is whether t...

The deformation of a leaf is the aggregation of the deformation of all the cells on the leaf. Mesophyll cells and vascular bundle cells have distinctly different degree of rigidity for shrinkage. In order to simulate the deformation of an autumn leaf realistically we need the realistic venation distribution of the leaf. We modify Runions’s technique [Runions et al. 2005] by increasing the growi...

Phytochemical investigation of Tanacetum parthenium L. family Asteraceae cultivated in Egypt resulted in isolation and identification of four flavonoids. One surface flavonoid was isolated from the fresh leaves and three other flavonoids were isolated from the flower heads. Four sesquiterpene lactones were isolated from the leaves. Two sterols were isolated from the roots. A comparative study o...

Lawsone a natural pigment present in the henna leaves has been used as a skin and hair dye since 1400 BC. The concentration of this natural compound in leaves varies from place to place depending upon many of the environmental factors and the highest quantity reported so far is about 1% of the dry mass. Heretofore, it has been reported that natural colored extracts and isolate from Henna leaves...

The present study was designed to explore the flavonoid contents and the radical scavenging activities of 50% ethanol extracts of leaves, stems, rachis and roots of Dryopteris erythrosora. The total flavonoid contents in various parts were determined as: stems > roots > rachis > leaves. All extracts from different parts of D. erythrosora showed strong bioactivities. The DPPH free radical scaven...