Monoxenic nodulation process of Acacia mangium (Mimosoideae, Phyllodineae) by Bradyrhizobium sp

Acacia mangium Willd., a native tree in Australia and Papua New Guinea, has been introduced to countries in Asia and South America where plantations have been established that cover several hundred thousand ha. The present study investigated the early stages of the nodulation process in A. mangium using an homologous Australian Bradyrhizobium strain. After optimizing the axenic nodulation, histological and cytological studies were conducted using light and electron microscopy. These documented the proliferation of Bradyrhizobium, the lysis of mucilage at the root surface, root hair deformation and initiation, as well as the development and growth of multiple infection threads. A belt of tannin-filled cells was shown to surround the central nodular fixation zone. The nodules were of the indeterminate type and the bacteroids had a rod shape, without size modification and with few polyhydroxybutyrate (PHB) granules. Several bacteroids can share the same symbiosome. A. mangium exhibits both classical and novel features in its nodulation.     

Characteristics of the Infection of Tilletia laevis Kühn (syn. Tilletia foetida (Wallr.) Liro.) in Compatible Wheat

Tilletia laevis Kühn (syn. Tilletia foetida (Wallr.) Liro.) causes wheat common bunt, which is one of the most devastating plant diseases in the world. Common bunt can result in a reduction of 80% or even a total loss of wheat production. In this study, the characteristics of T. laevis infection in compatible wheat plants were defined based on the combination of scanning electron microscopy, transmission electron microscopy and laser scanning confocal microscopy. We found T. laevis could lead to the abnormal growth of wheat tissues and cells, such as leakage of chloroplasts, deformities, disordered arrangements of mesophyll cells and also thickening of the cell wall of mesophyll cells in leaf tissue. What’s more, T. laevis teliospores were found in the roots, stems, flag leaves, and glumes of infected wheat plants instead of just in the ovaries, as previously reported. The abnormal characteristics caused by T. laevis may be used for early detection of this pathogen instead of molecular markers in addition to providing theoretical insights into T. laevis and wheat interactions for breeding of common bunt resistance.     

Plant material features responsible for bamboo's excellent mechanical performance: a comparison of tensile properties of bamboo and spruce at the tissue,fibre and cell wall levels

MethodsThe mechanical properties of single fibres and tissue slices of stems of mature moso bamboo (Phyllostachys pubescens) and spruce (Picea abies) latewood were investigated in microtensile tests. Cell parameters, cellulose microfibril angles and chemical composition were determined using light and electron microscopy, wide-angle X-ray scattering and confocal Raman microscopy.ConclusionsThe superior tensile properties of bamboo fibres and fibre bundles are mainly a result of amplified cell wall formation, leading to a densely packed tissue, rather than being based on specific cell wall properties. The material optimization towards extremely compact fibres with a multi-lamellar cell wall in bamboo might be a result of a plant growth strategy that compensates for the lack of secondary thickening growth at the tissue level, which is not only favourable for the biomechanics of the plant but is also increasingly utilized in terms of engineering products made from bamboo culms.     

Foraminifera and Nematoda community within the area of Ahnfeltia tobuchiensis field in Stark Strait (Peter the Great Bay of the Sea of Japan)

In August of 2006 in Stark Strait (in the Peter the Great Bay) Foraminifera and Nematoda communities were investigated at two stations: in bottom under a red alga Ahnfeltia tobuchiensis bed and on a site located outside of the bed. Bottom sediments at the stations are represented by sands of various silting extent. Foraminifera dominated at both stations, the second place by abundance was occupied by Nematoda. Extremely high population density of meiobenthos, 14278.9 ± 4623.1 thousand sp./m², was observed under the Ahnfeltia bed. The foraminifera percentage was 98.1%, which was probably connected with the mass development of diatom algae on Ahnfeltia. A high degree of domination of one Foraminifera species was recorded—Cribroelphidium frigidum. Nematoda constituted 1.5% with the prevalence of Comesomatidae family representatives. At the station situated outside of Ahnfeltia field mean population density of meiobenthos was an order lower—1731.8 ± 621.3 thousand sp./m². Foraminifera constituted 63.8% of the total meiobenthos density with Eggerella advena as the dominating species. Among Nematoda (12.5%) Paracanthonchus macrodon, Axonolaimus seticaudatus and Monoposthia latiannulata were dominant. Foraminifera and Nematoda community under Ahnfeltia bed, where bottom sediments are more silted, had low indices of species diversity and a high degree of domination.     

Reproduction systems of representatives of the genus Rosa L. under conditions of continental climate

The features of reproductive biology of rose plants from the sections Caninae Crep., Indocae Thory, Cinnamomae DC., Synstylae DC. were studied by cytological methods and with the help of scanning electron microscopy for many years. The results obtained are reported.     

New organic-walled Foraminifera (Protista) from the ocean's deepest point, the Challenger Deep (western Pacific Ocean)

We describe four new species and a new genus of very small (< 500 µm) Foraminifera from the Challenger Deep, the deepest point in the world's oceans (10 896 m water depth). All have transparent, mainly organic test walls that incorporate some minute agglutinated mineral particles of various shapes and compositions. Nodellum aculeata sp. nov. has an elongate proloculus with a pointed proximal end followed by a long, tubular section. The genus Resigella is represented by two species: in R. laevis sp. nov. , the test comprises 3–4 elongate, oval to cylindrical chambers while R. bilocularis sp. nov. has an oval proloculus followed by a second, larger globular chamber. The fourth species, Conicotheca nigrans gen. et sp. nov. , is characterized by a tiny, elongate, conical test filled with dark stercomata. Except in C. nigrans, the test wall has a brownish tinge; energy-dispersive spectroscopy (EDS) suggests the presence of organically bound Fe in all species including C. nigrans. Scanning electron microscopy (SEM) combined with EDS reveals distinctive wall structures. In N. aculeata, the proloculus is strewn with tiny (< 0.7 µm), elongate grains. In this species and in R. laevis, the test surface (except for the proloculus) is covered with a carpet of minute (∼0.1 µm) finger-like projections, rather similar to the organic cement of agglutinated Foraminifera. In R. bilocularis, the larger second chamber often has a partial veneer of fine mineral grains of varying composition, as well as organic areas consisting of meshed strands. SEM images of these three species reveal flat, plate-like features that we interpret as clay particles. In C. nigrans, the wall is relatively featureless except where the surface is raised into hummocky mounds and scale-like features, again probably clay particles. We suggest that these species represent a distinctive group of ‘agglutinated’ Foraminifera in which the test is predominately organic. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153 , 399–423.     

The effects of reformulating buffer species and their concentrations on subtilisin-catalyzed optical resolution of racemic 1-phenylethylamine in 3-methyl-3-pentanol

For the optical resolution of racemic 1-phenylethylamine in 3-methyl-3-pentanol, subtilisin was reformulated by lyophilization with buffer salts. The amide synthesis activity of subtilisin in organic solvent was compared with the hydrolysis activity in aqueous buffer when different buffer species and their concentrations were used in lyophilization. The enzyme activity in organic solvent showed a different pattern from that of the hydrolysis depending upon the species and the concentrations of buffers. Morphology of the reformulated subtilisin was examined by scanning electron microscopy (SEM). The porosity of reformulated subtilisin particles increased up to the optimal buffer concentrations for the amide synthesis in organic solvent. Glassy looks and decrease in porosity developed at high (i.e. above the optimal) buffer concentrations appear to affect the decrease in the synthetic activity in organic media.     

Benthic foraminiferal assemblages in the severely polluted coastal environment of Drapetsona-Keratsini,Saronikos Gulf (Greece)

Surface sediments were collected from the coastal zone of Drapetsona–Keratsini (Saronikos Gulf, Greece) in December 2012 for determining the local benthic foraminiferal community, identifying their spatial distribution patterns, and evaluating the response of foraminiferal species to geochemical composition through the hierarchical cluster analysis, principal component analysis and Spearman's rho correlation. Foraminifera can be classified into three distinct assemblages associated with the granulometry, elemental geochemistry, particulate organic carbon content and degree of sediment contamination. A relatively low-diversity assemblage, dominated by stress-tolerant taxa with Ammonia tepida Bolivina spathulata and Bulimina elongata being the prevailing species, is characteristic of the silty seabed of the main part of Drapetsona coastal zone and the Keratsini Port central basin, where organic carbon content, aliphatic and polycyclic aromatic hydrocarbons concentrations and trace metal loads are greatly elevated. On the sandy bottom of the investigated area, relatively high frequencies of miliolids prevail. An epiphytic rotaliid-dominated assemblage is recorded in the slightly-polluted sedimentary bottom of the inner and western part of the Keratsini Port.     

Synthesis, thermal stability and photoluminescence of new cadmium sulfide/organic composite hollow sphere nanostructures

Novel cadmium sulfide/organic composite hollow spheres composed of sword-like nanorods were synthesized via a simple reaction between cadmium salts and thioglycolic acid (TGA) at room temperature. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SEAD) and Fourier transform infrared (FT-IR) spectra. Thermal stability of the organic composite was investigated. CdS/organic composite would decompose into pure wurtzite CdS through hydrothermal treatment. Effect of the cadmium source on the formation of the CdS/organic composite was investigated. Photoluminescence (PL) was used to study the optical properties of CdS/organic composite and pure CdS.     

Preferential selection of titanium-bearing minerals in agglutinated Foraminifera: Ilmenite (FeTiO3) in Textularia hauerii d’Orbigny from the Bazaruto Archipelago, Mozambique

The biserial agglutinated foraminifer Textularia hauerii d’Orbigny frequently occurs at shallow depths in reefal habitats off Bazaruto Island, Mozambique. X-ray diffraction, scanning electron- and light microscopy analyses show the enhanced concentration of the titanium-bearing mineral ilmenite (FeTiO₃) in the agglutinated tests of this species. The mineral constitutes an insignificant component in the surrounding sediment (< 1%), but accounts for more than 26% of the foraminiferal test content. The accumulation of ilmenite in T. hauerii and its absence in co-occurring agglutinated Foraminifera suggest the preferential selection for ilmenite. The tendency for ilmenite particles to be arranged along sutures and on the apertural face (1) provides further evidence that certain Foraminifera can specifically select grains, and (2) implies that there exists a selective mechanism to control the timing and placement during test and chamber construction. The preferential uptake represents the first record of ilmenite selection in Foraminifera. Potential driving forces controlling the selective agglutination of Ti minerals, the preferential adsorption to Ti surfaces, and interactions between cellular compounds of the foraminiferal reticulopods and the mineral surfaces are explored.     

Latest Miocene-Pliocene Larger Foraminifera and depositional environments of the carbonate bank of La Désirade Island, Guadeloupe (French Antilles)

In this paper we present first results of the study of planktonic Foraminifera, large benthic Foraminifera and carbonate facies of La Désirade, aiming at a definition of the age and depositional environments of the Neogene carbonates of this island. The study of planktonic Foraminifera from the Detrital Offshore Limestones (DOL) of the Ancienne Carrière allows to constrain the biochronology of this formation to the lower Zone N19 and indicates a latest Miocene to early Pliocene (5.48-4.52 Ma) age. Large benthic Foraminifera were studied both as isolated and often naturally split specimens from the DOL, and in thin sections of limestones from the DOL and the Limestone Table (LT). The assemblages of Foraminifera include Nummulitidae, Amphisteginidae, Asterigerinidae, Peneroplidae, Soritidae, Rotalidae (Globigerinidae: Globigerinoides, Sphaeroidenellopsis, Orbulina) and incrusting Foraminifera (Homotrema and Sporadotrema). The genera Amphistegina, Archaias and Operculina are discussed. Concerning the Nummulitidae we include both “Paraspiroclypeus” chawneri and “Nummulites” cojimarensis, as well as a newly described species, Operculina desiradensis new species, in the genus Operculina, because the differences between these 3 species are rather on the specific than the generic level, while their morphology, studied by SEM, is compatible with the definition of the genus Operculina (D’Orbigny emend. Hottinger). The three species can be easily distinguished on the basis of their differences in spiral growth: while O. desiradensis has an overall logarithmic spiral growth, O. cojimarensis and especially O. chawneri show a tighter and more geometric spiral growth. O. cojimarensis and O. chawneri were originally described from Cuba in outcrops originally dated as Oligocene and later redated as early Pliocene. Therefore, O. chawneri was considered until now as restricted to the early Pliocene. However, in the absence of a detailed morphometric and biostratigraphic study of the Caribbean Neogene nummulitids, it is difficult to evaluate the biochronologic range of these species. The history of the carbonates begins with the initial tectonic uplift and erosion of the Jurassic igneous basement of La Désirade, that must have occurred at latest in late Miocene times, when sea-level oscillated around a long-term stable mean. The rhythmic deposition of the Désirade Limestone Table (LT) can be explained by synsedimentary subsidence in a context of rapidly oscillating sea-level due to precession-driven (19-21 kyr) glacio-eustatic sea-level changes during the latest Miocene-Pliocene. Except for a thin reef cap present at the eastern edge of the LT, no other in-place reefal constructions have been observed in the LT. The DOL of western Désirade are interpreted as below wave base gravity deposits that accumulated beneath a steep fore-reef slope. They document the mobilisation of carbonate material (including Larger Foraminifera) from an adjacent carbonate platform by storms and their gravitational emplacement as debris and grain flows. The provenance of both the reefal carbonate debris and the tuffaceous components redeposited in the carbonates of La Désirade must be to the west, i.e. the carbonate platforms of Marie Galante and Grande Terre.     

Foraminifera in the diet of coral reef fish from the lagoon of New Caledonia: Predation, digestion, dispersion

Marine benthic Foraminifera are abundant and thus represent a potential food source for fish. Previous studies of Foraminifera in fish diets have examined only small samples, with significant input reported only for a single surface-feeding species of fish. The present study is the first based on a significant sample (247 fish belonging to 83 species, 291 species of Foraminifera identified from more than 20,000 specimens examined). It provides new information on the contribution of Foraminifera to fish diets, and on the impact of fish predation on Foraminifera. The planktonic Tretomphalus phases, selectively ingested by Pomacentrus amboinensis, were the only significant nutritional input from Foraminifera. Herbivorous fish accidentally ingested living epiphytic Foraminifera, which were still living after digestion, and were defecated, with a significant effect on their dispersion. Carnivorous fish ingested a small number of tests, which were generally altered by the acidic phase of digestion and had no impact on foraminiferal assemblages. Sediment feeders ingested large quantities of empty tests that were released elsewhere, suggesting a possible bias in paleontological interpretations by mixing the thanatocoenoses. Observations on gut contents showed that the fish sometimes fed on a wide range of food, changing with food availability and individual preferences of fish.     

In vitro evaluation of the biomedical properties of chitosan and quaternized chitosan for dental applications

The aim of this study was to evaluate the potential dental applications of chitosan (CS) and N-[1-hydroxy-3-(trimethylammonium)propyl]chitosan chloride (HTCC). HTCC was prepared by reacting CS with glycidyltrimethylammonium chloride (GTMAC). CS and HTCC were characterized by infrared (FITR) and ¹H NMR spectroscopy. The antibacterial activity of CS and HTCC against oral pathogens, their proliferation activity and effects on the ultrastructure of human periodontal ligament cells (HPDLCs) were investigated. The results indicated that four oral strains were susceptible to CS and HTCC with minimum inhibitory concentrations (MICs) ranging from 0.25 to 2.5 mg/mL. The in vitro 3-(4,5-dimethyl-2-thizolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay determined that CS at 2000, 1000, 100, and 50 μg/mL could stimulate the proliferation of HPDLCs. Instead, HTCC inhibited the proliferation at the same concentrations but accelerated the proliferation of HPDLCs at relatively low concentrations (10, 3, 1.5, 1, and 0.3 μg/mL). Transmission electron microscopy (TEM) observations revealed that the ultra-architecture of HPDLC was seriously destroyed by HTCC treatment at 1000 μg/mL. Taken together, these results contribute information necessary to enhance our understanding of CS and HTCC in the dental field.     

Ecological succession among iron-oxidizing bacteria

Despite over 125 years of study, the factors that dictate species dominance in neutrophilic iron-oxidizing bacterial (FeOB) communities remain unknown. In a freshwater wetland, we documented a clear ecological succession coupled with niche separation between the helical stalk-forming Gallionellales (for example, Gallionella ferruginea) and tubular sheath-forming Leptothrix ochracea. Changes in the iron-seep community were documented using microscopy and cultivation-independent methods. Quantification of Fe-oxyhydroxide morphotypes by light microscopy was coupled with species-specific fluorescent in situ hybridization (FISH) probes using a protocol that minimized background fluorescence caused by the Fe-oxyhydroxides. Together with scanning electron microscopy, these techniques all indicated that Gallionellales dominated during early spring, with L. ochracea becoming more abundant for the remainder of the year. Analysis of tagged pyrosequencing reads of the small subunit ribosomal RNA gene (SSU rRNA) collected during seasonal progression supported a clear Gallionellales to L. ochracea transition, and community structure grouped according to observed dominant FeOB forms. Axis of redundancy analysis of physicochemical parameters collected from iron mats during the season, plotted with FeOB abundance, corroborated several field and microscopy-based observations and uncovered several unanticipated relationships. On the basis of these relationships, we conclude that the ecological niche of the stalk-forming Gallionellales is in waters with low organic carbon and steep redoxclines, and the sheath-forming L. ochracea is abundant in waters that contain high concentrations of complex organic carbon, high Fe and Mn content and gentle redoxclines. Finally, these findings identify a largely unexplored relationship between FeOB and organic carbon.     

Alkane-grown Beauveria bassiana produce mycelial pellets displaying peroxisome proliferation,oxidative stress,and cell surface alterations

The entomopathogenic fungus Beauveria bassiana is able to grow on insect cuticle hydrocarbons, inducing alkane assimilation pathways and concomitantly increasing virulence against insect hosts. In this study, we describe some physiological and molecular processes implicated in growth, nutritional stress response, and cellular alterations found in alkane-grown fungi. The fungal cytology was investigated using light and transmission electron microscopy while the surface topography was examined using atomic force microscopy. Additionally, the expression pattern of several genes associated with oxidative stress, peroxisome biogenesis, and hydrophobicity were analysed by qPCR. We found a novel type of growth in alkane-cultured B. bassiana similar to mycelial pellets described in other alkane-free fungi, which were able to produce viable conidia and to be pathogenic against larvae of the beetles Tenebrio molitor and Tribolium castaneum. Mycelial pellets were formed by hyphae cumulates with high peroxidase activity, exhibiting peroxisome proliferation and an apparent surface thickening. Alkane-grown conidia appeared to be more hydrophobic and cell surfaces displayed different topography than glucose-grown cells. We also found a significant induction in several genes encoding for peroxins, catalases, superoxide dismutases, and hydrophobins. These results show that both morphological and metabolic changes are triggered in mycelial pellets derived from alkane-grown B. bassiana.     

Spermatozoa and spermiogenesis of the wolf spider Schizocosa malitiosa (Lycosidae, Araneae) and its functional and phylogenetic implications

The wolf spider Schizocosa malitiosa is a well-known model system for studies on sexual selection in spiders. Despite this, little is known about the morphology of the reproductive system and spermatozoa in this species. In the present study, we investigate the male genital system and sperm cells of S. malitiosa using electron microscopy and provide a computer-based 3D reconstruction of the spermatozoa for the first time for arthropods. In general, the male genital system consists of two long, tube-like testes that lead into convoluted deferent ducts. The ejaculatory duct is enlarged and contains a large quantity of sperm and secretion. As revealed by transmission electron microscopy, only one type of secretion droplet is present in the seminal fluid. The spermatozoa of S. malitiosa resemble an organization known for members of the RTA clade, i.e., with an arrow-shaped acrosomal vacuole partly sunk into the nucleus and a chambered centriolar adjunct (a newly introduced character). This organization provides further support for these characters as potential synapomorphies for the RTA clade. By the end of the spermiogenesis, the nucleus and axoneme coils within the cell and a multi-layered secretion sheath are formed representing cleistospermia. The function of the thick secretion sheath is still unknown, but might be correlated either with the residency time in the female (insemination until oviposition) since female S. malitiosa do not lay eggs before the fourth month after copulation or with the receptivity-inhibiting substances suggested for this species.     

On the toxic effects of tetraethyl lead and its derivatives on the chrysophyte poterioochromonas malhamensis. IV. influence of lead antidotes and related agents

The unicellular alga Poterioochromonas malhamensis was exposed to 12.5 μM of inorganic or triethyl lead and simultaneously treated with lead antidotes and related agents at concentrations of 12.5, 31.25 and 62.5 μM. With increasing concentrations some of the antidotes alone slightly to severely inhibited algal growth (BAL¹, CaNa₂EDTA, EDTA, Na₂EDTA), whereas others (DPA, EGTA, DIZO) were non-toxic at the concentrations tested. EGTA and CaNa₂EDTA, at all concentrations tested, completely suppressed the growth inhibition caused by inorganic lead; Na₂EDTA and EDTA were protective at the lower or medium concentrations, but DIZO. DPA and BAL considerably enhanced lead toxicity with increasing concentrations. None of the tested agents was able to reduce the toxic effects of triethyl lead. All antidotes markedly increased inhibition of algal growth caused by triethyl lead and some were even lethal to the poisoned algae either at the highest (Na₂EDTA, EDTA, DPA) or at all concentrations used (DIZO, BAL). P. malhamensis proved to be a highly sensitive and valuable tests system and the results obtained exhibited striking parallels to medical and clinical experience in therapy of human poisoning with inorganic and organic lead compounds.     

Isolation of an extremely acidophilic and highly efficient strain Acidithiobacillus sp. for chalcopyrite bioleaching

An extremely acidophilic sulfur-oxidizing bacterium was isolated from an industrial-scale bioheap of the Zijinshan copper mine and was named ZJJN. A tuft of flagella and a layer of thick capsule outside the cell envelope were clearly observed under transmission electron microscopy (TEM), which might be closely related to the extremely acid-proof capacity of ZJJN cells in the bioleaching system; 16S ribosomal RNA (rRNA) phylogeny showed that the isolated strain was highly homologous to the genera of Acidithiobacillus. The optimum temperature of ZJJN was determined at 30?°C and pH at 1.0. It was capable of growth at even pH 0. Strain ZJJN can utilize reduced sulfur as an energy source but not with organics or ferrous ion. Strain ZJJN was sensitive to all antibiotics with different concentrations; when it showed a certain resistance to different concentrations of Cu²⁺. In the mixed strains of ZJJN and A. ferrooxidans system (initial pH 1.0), the copper-leaching efficiency was up to 60.1?%, which was far higher than other systems. Scanning electron microscopy (SEM) analysis showed that less jarosite precipitation was produced in the most efficient system. The extremely acidophilic strain ZJJN would be of great potential in the application of chalcopyrite bioleaching.     

Effects of Cigarette Smoke Extracts on the Growth and Senescence of Skin Fibroblasts In Vitro

Epidemiological studies have shown that cigarette smoke (CS), a very common environmental factor, plays an important role in skin aging. Although some in vivo studies have suggested that CS affects skin aging, the detailed effects of CS on skin cells in vitro remain largely unknown. In this study, we investigated the effects of cigarette smoke extract (CSE) on the growth, proliferation, and senescene of skin fibroblasts and the possible mechanism underlying these effects. Primary cultured human fibroblasts were exposed to a range of concentrations of CSE. Cell viability and cell proliferation after CSE exposure were analyzed with the methyl thiazolyl tetrazolium (MTT) assay and bromodeoxyuridine incorporation assay, respectively. Growth curves of fibroblasts exposed to different concentrations of CSE were developed and prolonged CSE-exposed cells were observed. Morphological and ultrastructural changes in fibroblasts were assessed by inverted light microscopy and transmission electron microscopy (TEM). Dying cells were stained with senescence-associated β-galactosidase (SA β-gal). Intracellular reactive oxygen species (ROS) levels, superoxide dismutase (SOD) activity, and glutathione peroxidase (GSH-Px) activity were determined by a colorimetric method. We found that proliferative capacity and growth were inhibited by CSE exposure in a dose- and time-dependent manner. Fibroblasts exposed to even low concentrations of CSE for a long period of time (5 passages) showed significantly increased SA β-gal activity and typical features of aging cells. Meanwhile, CSE inhibited superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and augmented ROS levels. Our observations suggest that CSE exposure impairs fibroblast growth and proliferation and leads to features similar to those seen in senescent cells. Oxidative stress injury and inhibition of antioxidant defense activity may be involved in CSE-induced fibroblast senescence.     

Brain glycogen during non-diapausing and diapausing development of Pieris brassicae larvae and pupae

Summary

Histological and cytological localization of glycogen was studied in the brain of Pieris brassicae larvae and pupae by histochemistry and electron microscopy. The major glycogen deposits were observed in glial cells located between the cortex and the neuropile and also in perineurial cells. The concentrations of brain glycogen were measured in the larvae and the pupae during non-diapausing and diapausing development. In addition, we demonstrated that starvation reduces the density of the brain glycogen deposits as well as the concentrations of glycogen.