Comparative LM, SEM and EDAX study of chalk glands on leaf and stem of two species of Plumbago Linn.

Stem and leaves of two species of PlumbagoLinn.viz. P. zeylanica Linn.andP. auriculata Lam. were investigated for the structure and chemical composition of chalk glands. Light Microscopy (LM) and Scanning Electron Microscopy (SEM) revealed the presence of chalk glands on both lower as well as upper surface of leaf and stem of both species. Chalk glands are abundant on lower surface and sparse on upper surface of leaf. Chalk glands are approximately hemispherical glands with oval or almost circular outline. It is composed of 8 cells arranged in two circles – central circle of 4 secretory cells and outer circle of 4 adjoining cells. Each secretory cell has depression which corresponds to pore. Each gland is surrounded by 4 subsidiary cells. No significant difference in the structure of chalk glands in both species was noticed. Chalk glands occupy three different positions with regard to epidermal cells –at the same level of the epidermis, slightly sunken in the epidermis and slightly raised above the epidermis. Common elements found in EDAX analysis of all chalk glands are carbon, oxygen, magnesium, sulphur, potassium and calcium. Differences in the presence of elements silicon, chlorine, aluminium, sodium, phosphorus were observed. The presence of significant amount of calcium in chalk glands and their dried deposits and absence of sodium and chlorine from dried deposits and even in some chalk glands appealed to use the term ‘Chalk gland’ instead of ‘Salt gland’ in Plumbago.

Ultrastructure and energy dispersive spectroscopy-based elemental analysis of the fruit exocarps of Musa sinensis L. (Banana) and Musa paradisiaca L. (Plantain) (Musaceae)

Ultrastructural investigation and analysis of the elemental spectra composition of Musa sinensis L. and Musa paradisiaca L. exocarp (peels) was carried out using the Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray (EDX) respectively. Microstructures such as interlocked, polyhedral epidermal cells, ellipsoid-shaped stomata, guard cells, intercellular space, anticlinal-patterned walls and subsidiary cells were observed, with direct and indirect implications in the deposition of important primary and secondary metabolites, thus connoting some medicinal significance. Furthermore, the energy dispersive x-ray spectra revealed the presence of some important elements such as potassium (K), iron (Fe), carbon (C), oxygen (O), silicon (Si) and gold (Au), with high to relatively high carbon and oxygen peaks consistently observed in Musa sinensis and Musa paradisiaca. In the same vein, the relative similarity observed in the constituents of quite a number of the elemental spectra (carbon, oxygen, silicon, gold) in M. sinensis and M. paradisiaca peels, also reflects species relatedness between M. sinensis and M. paradisiaca.

A simple method for exogenously phytohormone application to the protodermal areas in the base of maize (Zea mays L.) leaf

Background: The maize leaf epidermis is function as protection against water loss and gas exchange, contacting the environment and avoiding the damage, which is an attractive system for studying the process of cell fate and development. In monocots, leaves epidermis grown from basal meristem, which contains protodermal cells. The leaf protoderm zone was covered by the leaf sheath or coleoptile in maize, the classic exogenously phytohormone application method, such as spraying on leaf surface or adding in the culture media can’t apply the phytohormone to the protoderm areas directly, which restricts the research about phytohormone effect epidermal development.Results: Here we described a simple and direct method for exogenously application of phytohormone to maize leaf protoderm. We use the auxin analogs 2,4-D to test the system, and the asymmetrical division events which initial stomata development were decreased and the subsidiary cells were induced in advance after 2,4-D treatment. This result was the same as other similar studies’ results, indicated that the method is suitable for been used for application phytohormone to the maize leaf protodermal areas.Conclusions: The method, applied hormones on the mesocotyls of the maize seedlings, is simple and direct. Only a small amount of externally applied substances is required to complete this experiment through this method. The entire experiment process just last 10 days generally and it is easy to survey the phytohormone's effect on the epidermis development.

Bennettitalean Leaves From the Permian of Equatorial Pangea—The Early Radiation of an Iconic Mesozoic Gymnosperm Group

Bennettitaleans are an extinct group of gymnosperms that are among the most iconic plants of Earth’s vegetation during the Mesozoic Era. The sudden appearance and rise to dominance of the Bennettitales during the Triassic remains a mystery. Leaf fossils similar to typical bennettitalean foliage occur in late Paleozoic deposits worldwide, but bennettitalean foliage can be identified with certainty only in case the fossils are sufficiently well-preserved to show epidermal features. So far, the characteristic stomatal architecture of the group has never been systematically documented in these putative Paleozoic remains. Here, we present well-preserved bennettitalean leaves from Permian deposits in two widely separated regions of equatorial Pangea. Two species of cuticle-bearing leaf compressions from the late Permian Umm Irna Formation, Jordan, are here formally described as Pterophyllum pottii Bomfleur et Kerp sp. nov. and Nilssoniopteris jogiana Blomenkemper et Abu Hamad sp. nov. Moreover, bulk maceration of samples from the Umm Irna Formation yielded six additional types of dispersed bennettitalean cuticles that are here informally described. In addition, the Cisuralian (early Permian) uppermost part of the Upper Shihhotse Formation exposed at the Palougou section in Shanxi Province, China, has yielded the oldest unambiguous bennettitalean fossils known to date; they consist of fragments of entire-margined leaves with well-preserved cuticles that we assign to Nilssoniopteris shanxiensis Bäumer, Backer et Wang sp. nov. Unlike the characteristic puzzle-patterned cuticles typical of many Jurassic and Cretaceous bennettites, the cuticles of these Permian bennettitalean remains show non-sinuous anticlinal walls, greater variety in stomatal orientation, and rare occurrence of transversely divided subsidiary cells—features that have until now almost exclusively been documented from the hitherto oldest cuticle-bearing Triassic bennettitalean material. Finally, the taxonomic richness, disjunct distribution, and broad variety in macro- and micromorphological features in these Permian bennettitalean remains lead us to suspect that the origin of the group will date back still further in time, and might in fact coincide with very early occurrences of Bennettitales-like foliage from the Pennsylvanian and Cisuralian, such as Pterophyllum cottaeanum, P. eratum, or P. grandeuryi.

Stomatal rings: structure, functions and origin

Stomatal rings are structural elements of stomata of some flowering plants, being found in various groups of eudicots. The presence of a stomatal ring on a stoma does not depend on stomatal complex types, dimensions of stomata or their density. The guard cells of these stomata lie on the subsidiary cells. The location of the outer ledges on the outer tangential walls of the guard cells and the position of the stomatal rings on the guard cell walls around the outer ledges or on the outer ledges themselves are also among the characteristic features of these stomata. To elucidate the role of the stomatal rings we applied modelling using the finite-element method. The modelling has shown that the outer ledges prevent movements of the outer tangential walls of the guard cells and stimulate movements of the inner tangential walls and the immersion of the opening stomatal pore in the epidermis. Stomatal rings can enhance this effect. They also prevent the movements of the outer ledges and the widening of the stomatal aperture between them during stoma opening. This type of stomata occurs in evergreen plants growing in diverse conditions.

Why one species in New Zealand, Pugetia delicatissima (Kallymeniaceae, Rhodophyta), should become two new genera, Judithia gen. nov. and Wendya gen. nov.

© 2015 British Phycological Society. Blade-forming red algae occur worldwide and, prior to DNA sequencing, had been notoriously difficult to identify and classify, especially when lacking critical reproductive features. This, coupled in New Zealand with many longstanding assumptions that taxa were identical to non-New Zealand species or genera, resulted in many misapplied names. Pugetia delicatissima R.E. Norris, an endemic New Zealand blade-forming species of the family Kallymeniaceae, is actually comprised of one existing and one new species belonging to two distinct genera, as established by our phylogenetic analyses of DNA sequences from the rbcL gene. Analyses of combined rbcL and LSU genes showed that neither is closely related to the generitype of Pugetia, the northern-eastern Pacific, P. fragilissima Kylin. We propose the names Judithia and Wendya for these two newly revealed genera. In addition to diagnostic rbcL and LSU sequences, Judithia is morphologically and anatomically characterized by rounded to oblong blades that do not taper basally at the stipe, loosely aggregated surface cortical cells and cystocarps lacking both a pericarp and an ostiole, all features observed in the holotype of P. delicatissima. Wendya, in contrast, is characterized by blades that taper both apically and basally, compactly arranged surface cortical cells and cystocarps that have both a pericarp and a distinct ostiole. The two genera also are distinguished from one other, as well as from Pugetia by features of pre- and post-fertilization development, including the number of subsidiary cells produced on carpogonial and auxiliary branch systems, whether subsidiary cells in the carpogonial branch system fuse with the supporting cell or not, and the site of origin of gonimoblast cells. Although small in area, New Zealand hosts ten of the 27 currently recognized genera in the Kallymeniaceae and is the southern-hemisphere region of greatest generic diversification in this family.

Why one species in New Zealand, Pugetia delicatissima (Kallymeniaceae, Rhodophyta), should become two new genera, Judithia gen. nov. and Wendya gen. nov.

© 2015 British Phycological Society. Blade-forming red algae occur worldwide and, prior to DNA sequencing, had been notoriously difficult to identify and classify, especially when lacking critical reproductive features. This, coupled in New Zealand with many longstanding assumptions that taxa were identical to non-New Zealand species or genera, resulted in many misapplied names. Pugetia delicatissima R.E. Norris, an endemic New Zealand blade-forming species of the family Kallymeniaceae, is actually comprised of one existing and one new species belonging to two distinct genera, as established by our phylogenetic analyses of DNA sequences from the rbcL gene. Analyses of combined rbcL and LSU genes showed that neither is closely related to the generitype of Pugetia, the northern-eastern Pacific, P. fragilissima Kylin. We propose the names Judithia and Wendya for these two newly revealed genera. In addition to diagnostic rbcL and LSU sequences, Judithia is morphologically and anatomically characterized by rounded to oblong blades that do not taper basally at the stipe, loosely aggregated surface cortical cells and cystocarps lacking both a pericarp and an ostiole, all features observed in the holotype of P. delicatissima. Wendya, in contrast, is characterized by blades that taper both apically and basally, compactly arranged surface cortical cells and cystocarps that have both a pericarp and a distinct ostiole. The two genera also are distinguished from one other, as well as from Pugetia by features of pre- and post-fertilization development, including the number of subsidiary cells produced on carpogonial and auxiliary branch systems, whether subsidiary cells in the carpogonial branch system fuse with the supporting cell or not, and the site of origin of gonimoblast cells. Although small in area, New Zealand hosts ten of the 27 currently recognized genera in the Kallymeniaceae and is the southern-hemisphere region of greatest generic diversification in this family.

A Review on Macroscopy, Microscopy and Pharmacological Activity of Cayratiatrifolia Linn.

Cayratiatrifolia (Linn.)Domin is a perennial climber, family Vitaceae, found in India, Asia and Australia. The plant is found in hilly regions as well as the hotter part of India from Jammu and Rajasthan to Assam. It is commonly known as fox grape in English, Amalbel, Ramchana in Hindi and Amlavetash in Sanskrit. The plant has trifoliated leaves with (2-3cm) long petioles and ovate to oblong-ovate leaflets. Flowers are small greenish white and brown in colour. Fruits are fleshy, juicy, spherical, about 1 cm in diameter of dark purple or black colour.The stem composed of cork cells on the outer side and composed of small size sclerenchymatous cells. The cortex is wide and has parenchymatous cells. Numbers of sclereids are widely distributed in the cortex region. Cortex also shows the presence of calcium oxalate crystals.The leaf surface shows the stomata covered with guard cells followed by epidermis layer (Figure2A). Epidermal cells are rectangular, thin and straight walled cells. Stomata are anisocytic or unequal celled stomata, three subsidiary cells, one is smaller than other two. Leaf surface analysis also shows the presence of veins, vein islet and vein termination (Figure2B). Transverse section of leaf shows the epidermis layer followed by cuticle layer and vascular bundles (xylem and phloem).The leaf powder is pale green in color, with a characteristic odour and bitter taste.This plant also contains kaempferol, myricetin, quercetin, triterpenes and epifriedelanol. Whole plant of Cayratiatrifolia has been reported to contain yellow waxy oil, steroids/terpenoids, flavonoids, tannins. Plant shows the antioxidant, antidiabetic, antibacterial, antiviral and anticancer activity.