Chansitheca wudaensis (Gleicheniaceae,fern) from the early Permian Wuda Tuff Flora,Inner Mongolia

A large number of specimens of Chansitheca wudaensis Deng, Sun et Li from the early Permian Wuda Tuff Flora allow an emendation of this species. Characters of the sporangial structure and in situ spores are examined for the first time. Sori are arranged on lateral veins of pinnule lobes, and are 0.61–0.69 mm long and 0.35–0.41 mm wide. Sporangia are sessile and surrounded by an annulus, which is composed of two rows of oblong thick-walled cells. Trilete, smooth in situ spores have diameters of 21.05–26.31 μm. Features of the reproductive organ indicate that this species is similar to Szea Yao et Taylor and some species of Oligocarpia Goeppert and belongs to the Gleicheniaceae. Based on a taphonomical analysis, C. wudaensis was an herbaceous element of the groundcover in the peat-forming coal swamp.     

Interactive effects of selenium and arsenic on their uptake by Pteris vittata L. under hydroponic conditions

The interactive effects of selenium (Se) and arsenic (As) on plant uptake of Se and As have rarely been documented. In this study, the interactive effects of As and Se on their uptake by Chinese brake fern (Pteris vittata), an As-hyperaccumulator and Se-accumulator, were explored in two hydroponic experiments based on a two-factor, five-level central composite design. At Se levels of less than 2.5 mg L^?1, increasing amounts of As stimulated the uptake of Se in Chinese brake fern roots, possibly because of the beneficial effects of Se. In contrast, at Se concentrations greater than 2.5 mg L^?1, As suppressed the uptake of Se in Chinese brake fern roots. Uptake of As by both fronds and roots of Chinese brake fern was suppressed by the addition of Se, indicating the antagonistic effects of Se on As. In addition, at Se concentrations of less than 2.5 mg L^?1, As stimulated the translocation of Se from roots to fronds; meanwhile, the addition of Se resulted in reduced translocation of As from roots to fronds. These findings demonstrate the interactive effects of As and Se on their uptake by Chinese brake fern.     

STUDIES OF PALEOZOIC MARATTIALEANS: THE MORPHOLOGY AND PROBABLE AFFINITIES OF TELANGIUM PYGMAEUM GRAHAM

Telangium pygmaeum Graham is known from Upper Pennsylvanian coal balls from the Calhoun coal mine (Illinois). The species was described as possessing radial synangia consisting of 3-5 sporangia fused laterally for about f13 their length. Synangia were believed to be sessile and borne terminally or laterally on a branching rachis without lamina. Examination of new coal ball material of the same age indicates that the synangia are borne abaxially on the pinnules of a compound frond with the anatomy of a Psaronius leaf (Marattiales). Synangia are sessile and borne in two rows, one on either side of the pinnule midrib, under the unbranched lateral veins. Synangia are radial, 0.6 mm in diam, and consist of a ring of thin-walled sporangia fused to near their apices prior to dehiscence, but separating on dehiscence to release spores along their inner midline. Spores are spherical, trilete, 30-48 μm in diam, with a granulate ornamentation. The new genus Araiangium is proposed for this material based on the organization of the sessile thin-walled synangia. Araiangium is compared with other marattialean genera with sessile synangia (Acaulangium, Acitheca), and with the pedicellate synangia of various species of Scolecopteris. Criteria used in the delimitation of genera in Paleozoic anatomically preserved marattialean fertile foliage are discussed.     

Seed storage and germination in Kumara plicatilis,a tree aloe endemic to mountain fynbos in the Boland,south-western Cape,South Africa

Seed storage under appropriate conditions is a relatively inexpensive means of safeguarding plant genetic material for ex situ conservation. Post-storage germination trials are used to determine the viability of stored seeds, and hence the efficacy of the particular storage treatment. Kumara plicatilis (= Aloe plicatilis) is a tree aloe endemic to mountain fynbos in the Boland, south-western Cape. The viability and germination behaviour of K. plicatilis seeds were assessed for seeds stored for four and nine months at − 80 °C, 4 °C, 25 °C and under ambient conditions in a laboratory. Seeds were germinated under controlled conditions and germination rates and percentages determined. Ungerminated seeds were tested for viability using tetrazolium salt. Seed viability was not significantly reduced during storage. Seeds stored at − 80 °C for four and nine months exhibited the fastest germination rate overall (both 5.9 ± 0.3 weeks, mean ± S.E.), and slowest was for seeds stored under ambient conditions for four and nine months (both 7.8 ± 0.4 weeks). All seed lots showed similar percentage germination after four months of storage (78.0–90.4%). The highest percentage germination overall was for seeds stored at − 80 °C for four months (90.4%) and the lowest was for seeds kept at 4 °C and − 80 °C for nine months (39.2 and 39.6%, respectively). Respective percentage viability for ungerminated seeds in these two treatments was 82% and 87%, respectively, indicating the induction of secondary dormancy. Induced dormancy triggered by protracted cold temperatures may be an adaptation that enables seeds to survive prolonged extreme conditions that are unfavourable for germination. Further research on the long-term storage of aloe seeds would be beneficial for developing long-term seed storage and germination testing protocols for ex situ conservation.     

First evidence of cell deformation occurrence during a Dinophysis bloom along the shores of the Gulf of Tunis (SW Mediterranean Sea)

Never before observed or cited in Dinophysis studies, deformations in Dinophysis acuminata and Dinophysis sacculus are reported throughout their cellular division phases (cytokinesis, and sulcal list regeneration) in 5 in situ cell cycle studies in the Punic harbors of Carthage (northern Tunisia). Two types of deformation were observed: invaginations in the ventral and dorsal margin and protuberances at the base of the left sulcal list. No virus or bacteria were detected with Syber green stain. In situ division rates (μ) varied among seasons and stations for the same species. D. acuminata exhibited moderate (0.22 day⁻¹) to high (0.68 day⁻¹) μ rates which were however very low (0.02–0.17 day⁻¹) for D. sacculus in autumn and moderate (0.21–0.35 day⁻¹) in late spring. In 2009 the seasonal distribution of Dinophysis indicates maximum Dinophysis cf. ovum abundance in March and a high number of D. acuminata in early June, while in 2010 maximum abundance of the same species was found in mid-June.Molecular and genetic studies and staining with specific fluorescent strains should be addressed to hopefully explain these Dinophysis cell deformations during their in situ division.     

Isolation,purification and biochemical characterization of dipeptidyl peptidase-III from germinated Vigna radiata seeds

Genome analysis of plants indicated majority of putative protease genes that need characterization at enzymatic and molecular level. Proteases execute important role in seed development but knowledge of dipeptidylpeptidases in seeds is limited. A dipeptidylpeptidase-III that cleaves Arg-Arg from Arg-Arg-4mβNA was purified from germinated Mung bean seeds. Screening of cereals and legumes for DPP-III revealed highest activity in Phaseolus vulgaris and Vigna radiata (variety P.9531) seeds germinated for 48 h. Homogenate (10%) was acid precipitated upto pH 4.2 and then subjected to 0–55% ammonium sulphate precipitation followed by successive chromatographies on cation exchanger, gel filtration and anion exchanger. Enzyme purity was confirmed by native polyacrylamide gel electrophoresis and in situ gel assays. DPP-III is a heterodimer of ～60 kDa with two subunits of 32.8 kDa and 27 kDa on SDS-PAGE. DPP-III worked optimally at pH 8.0 and at 37 °C with pH stability between 7.5 to 9.5. Arg-Arg-4mβNA was preferred substrate and none of endopeptidase and monopeptidase substrates were hydrolysed. Inhibitors studies revealed it as thiol protease with involvement of metals at active site. The enzyme might be involved in plant's development by generating/deactivating bioactive peptides. Further studies on functional characterization and molecular structure are in progress in our laboratory.     

Real-time observation,early warning and forecasting phytoplankton blooms by integrating in situ automated online sondes and hybrid evolutionary algorithms

Phytoplankton bloom is one of the most serious threats to water resource, and remains a global challenge in environmental management. Real-time monitoring and forecasting the dynamics of phytoplankton and early warning the risks are critical steps in an effective environmental management. Automated online sondes have been widely used for in situ real-time monitoring of water quality due to their high reliability and low cost. However, the knowledge of using real-time data from those sondes to forecast phytoplankton blooms has been seldom addressed. Here we present an integrated system for real-time observation, early warning and forecasting of phytoplankton blooms by integrating automated online sondes and the ecological model. Specifically, based on the high-frequency data from automated online sondes in Xiangxi Bay of Three Gorges Reservoir, we successfully developed 1–4 days ahead forecasting models for chlorophyll a (chl a) concentration with hybrid evolutionary algorithms (HEAs). With the predicted concentration of chl a, we achieved a high precision in 1–7 days ahead early warning of good (chl a < 25 μg/L) and eutrophic (chl a 8–25 μg/L) conditions; however only achieved an acceptable precision in 1–2 days ahead early warning of hypertrophic condition (chl a ≥ 25 μg/L). Our study shows that the optimized HEAs achieved an acceptable performance in real-time short-term forecasting and early warning of phytoplankton blooms with the data from the automated in situ sondes. This system provides an efficient way in real-time monitoring and early warning of phytoplankton blooms, and may have a wide application in eutrophication monitoring and management.     

Davallia (Polypodiales: Davalliaceae) macrofossils from Early Miocene Otago (New Zealand) with in situ spores

Fossil fern fronds referable to the extant fern genus Davallia (Polypodiales: Davalliaceae) bearing sporangia with in situ spores are described from the Early Miocene Foulden Maar diatomite deposit, Otago, New Zealand. The fronds are the first published Southern Hemisphere macrofossil record for the family and provide valuable palaeoclimate data supporting warm conditions in Early Miocene New Zealand. The matching of Davallia fronds to the form spore taxon Polypodiisporites radiatus shows that the genus has had a long, apparently continuous history throughout late Cenozoic New Zealand.     

First results from conservation studies of chlorophyllous spores of the Royal fern (Osmunda regalis, Osmundaceae)

Pteridophytes spore banks are a promising ex situ conservation tool used to increase the chances of survival of ferns, in fact that large quantities of germplasm with high genetic variation can be conserved in a small space with low economic and technical costs. However, methods to maintain the viability of chlorophyllous spores during storage are less understood.The aim of this study was to investigate the influence of long term storage on the viability of Royal Fern spores, which were stored under different conditions derived from various combinations of temperature and degrees of hydration. Survival and germination tests were performed after 1 and 28 months of storage. Our results showed the highest survival percentages for spores stored under Normal humidity at subzero temperatures (T = ? ?20 °C). These spores received no pre-treatment, dehydration, or cryoprotectants, which resulted in fast germination and gametophyte development which seemed to be stimulated by low temperatures.     

Spatial and temporal variation in density and thallus morphology of Turbinaria ornata in Thailand

Turbinara ornata (Turner) J. Agardh, is a common brown alga, which occurs on tropical shores worldwide. We studied the effects of wave action and seasonal variation on T. ornata populations at Koh Pling, Sirinart Marine National Park, Thailand. Density, length of thallus, length of blade, number of blades, number of reproductive organs, and dry weights were investigated. The algae were collected bimonthly during August 2003–May 2004, at three different areas of wave exposure: sheltered, semi-exposed, and exposed. There were variations in all factors at sites and seasons (P < 0.05). We found that T. ornata populations were denser on the semi-exposed shore and their biological characteristics reached their peaks during October 2003. The highest density of T. ornata was 27 ± 10 fronds/m² (mean ± S.E.). While the average frond length, for example, was 24 ± 1.5 cm, 4 times greater than the minimum; and the number of blades on the thallus were 329 ± 47 blades, 15 times greater than the minimum. Surprisingly, the population disappeared at the beginning of May 2004, and returned in July 2004. In this work, we attempt to explain the differences in various characteristics of T. ornata in relation to the degree of wave exposure, nutrient concentration and other physical factors. We also discuss how our results may provide some insight into the current rapid expansion of T. ornata populations.     

Marine snow formation by the toxin-producing diatom,Pseudo-nitzschia australis

The formation of marine snow (MS) by the toxic diatom Pseudo-nitschia australis was simulated using a roller table experiment. Concentrations of particulate and dissolved domoic acid (pDA and dDA) differed significantly among exponential phase and MS formation under simulated near surface conditions (16 °C/12:12-dark:light cycle) and also differed compared to subsequent particle decomposition at 4 °C in the dark, mimicking conditions in deeper waters. Particulate DA was first detected at the onset of exponential growth, reached maximum levels associated with MS aggregates (1.21 ± 0.24 ng mL⁻¹) and declined at an average loss rate of ∼1.2% pDA day⁻¹ during particle decomposition. Dissolved DA concentrations increased throughout the experiment and reached a maximum of ∼20 ng mL⁻¹ at final sampling on day 88. The succession by P. australis from active growth to aggregation resulted in increasing MS toxicity and based on DA loading of particles and known in situ sinking speeds, a significant amount of toxin could have easily reached the deeper ocean or seafloor. MS formation was further associated with significant dDA accumulation at a ratio of pDA: dDA: cumulative dDA of approximately 1:10:100. Overall, this study confirms that MS functions as a major vector for toxin flux to depth, that Pseudo-nitzschia-derived aggregates should be considered ‘toxic snow’ for MS-associated organisms, and that effects of MS toxicity on interactions with aggregate-associated microbes and zooplankton consumers warrant further consideration.     

Proliferation of the toxic dinoflagellate Ostreopsis cf. ovata in relation to depth,biotic substrate and environmental factors in the North West Mediterranean Sea

In recent decades, the North West Mediterranean Sea has been seriously affected by the development of the toxic benthic dinoflagellate Ostreopsis cf. ovata, which is associated with harmful effects on human health and the environment. The present work aims to provide a large overview of the multiple environmental factors assumed to regulate or influence the growth of Ostreopsis. An intensive sampling campaign over a full annual cycle was performed along the French and Italian coasts (in six sites from Cassis to Genoa), to determine patterns of temporal and spatial distributions of both O. cf. ovata epiphytic and planktonic cells. Results highlighted substantial seasonal variations in the abundance of Ostreopsis. These variations correlated to seawater temperature, with an optimum growth temperature ranging from 23 °C to 27.5 °C. Phosphate concentration, rather than nitrogen or silicate, was also positively associated with Ostreopsis. Decreases in oxygen and increases in chlorophyll a concentrations were recorded during the summer blooming period. The maximal Ostreopsis epiphytic abundance was generally higher on Dictyota spp. than on the other two sampled macroalgae (up to 8.54 × 10⁶ cells g⁻¹ FW), even though statistical analysis did not support a clear substrate preference. Epiphytic abundances were significantly higher at a very shallow depth (0.5 m), than at 1 and/or 3 m depths. High anthropogenic pressure (related to population density) seems to have promoted the occurrence of blooms in urbanized areas, which could partly explain the strong demarcation in Ostreopsis development between Western and Eastern sampling sites. The ecological niche of Ostreopsis cf. ovata needs precise definition, which will require further in situ and in vitro experimental studies, to determine the relative importance of distinct environmental parameters.     

Population structure and genetic diversity of Dysosma versipellis (Berberidaceae), a rare endemic from China

Dysosma versipellis (Berberidaceae) is an endangered and endemic species in China. To provide scientific foundation for formulating conservation strategies, we sampled six extant populations of this species and assessed the levels and patterns of genetic diversity using ISSR markers (11 primers). Of 144 bands detected 57.64% were polymorphic, but on average only 20.72% were polymorphic within populations. Our results revealed a low level of intraspecific genetic diversity (at population level: H_pop = 0.082, H_B = 0.177, SI = 0.1194; at species level: H_pop = 0.207, H_B = 0.378, SI = 0.3069). A high level of genetic differentiations among populations was detected based on Nei's genetic diversity analysis (60%), AMOVA analysis (65%), and Bayesian analysis (53%). The low levels of heterozygosity and high genetic differentiation observed in D. versipellis may be the consequence of low rate of natural recruitment, clonal growth, gene drift, and habitat fragmentation. Based on this, we suggest that in situ conservation be an important and practical measure for maintaining the genetic diversity of this species. Ex situ conservation should sample from different populations across the distribution range of the species to conserve high genetic diversity.     

Middle Jurassic Ginkgo leaves from the Daohugou area,Inner Mongolia,China and their implication for palaeo-CO2 reconstruction

Well-preserved Ginkgo leaves with cuticle were collected from the Middle Jurassic Jiulongshan Formation in the Daohugou area, Inner Mongolia, China, which form the common elements in the Daohugou flora. Three new species of Ginkgo are recognized and their leaf morphology and cuticular structure are described for the first time. Two different pCO₂ proxy models were applied to reconstruct palaeo-atmospheric CO₂ concentration by using these new Ginkgo material. NLE (nearest living equivalent) suggests a semi-quantitative pCO₂ estimate as 839 ± 99 ppmv with Carboniferous standardization and 419 ± 49 ppmv with Recent standardization. While Barclay’s revised SI-pCO₂ regression suggests the estimates as 405 ± 71 ppmv. The results show that the pCO₂ estimate is higher than today’s atmospheric CO₂ concentration but lower than most of the other results on the Jurassic Period. Combined with the floristic composition, the climate at 165 Ma in the Daohugou area is inferred to be warm temperate.     

Soundness of in situ lipid biomarker analysis: Early effect of heavy metals on leaf fatty acid composition of Lactuca serriola

In previous studies we proposed the plant leaf fatty acid composition, and more precisely the ratio C18:3/(C18:0 + C18:1 + C18:2) as a tool to diagnose soil contamination ex situ. These studies led us to normalize this parameter as a biomarker of soil quality using Lactuca sativa growing under controlled conditions as the plant model species. The evaluation of the toxic effects of pollutants is more difficult to grasp in a real and more complex environment. Hence we developed a study to test the hypothesis that plant leaf fatty acid composition could be used also as a reliable tool to diagnose soil contamination in situ. We tested whether Lactuca serriola (prickly lettuce) could be used as a plant model species for such studies, primarily because it is widely distributed in various European countries and recorded at different habitats, and regarded as an ancestor of the cultivated lettuce L. sativa that was used for ex situ experiments. The results show that the lipid biomarker values were significantly lower in leaves of L. serriola grown on a metallurgic landfill soil than in leaves of plants harvested on surrounding countryside areas. To determine whether the value of the lipid biomarker in L. serriola leaves could be correlated to the soil metal content, we also measured the metal content of the soil corresponding to the rhyzospheric areas from where the prickly lettuce leaves were harvested. The results of the Principal Component Analysis (PCA) show that the lipid biomarker is negatively correlated with both Ni and Cr content. Moreover, these results show that the lipid biomarker values measured in situ were repeatable from year to year, confirm that this biomarker measured in situ would provide an early indication of a plant's exposure to metal, and could be therefore used to facilitate or strengthen the diagnosis of soil contamination.     

Arsenic reduced scale-insect infestation on arsenic hyperaccumulator Pteris vittata L.

Arsenic hyperaccumulation by Pteris vittata L. (Chinese brake fern) may serve as a defense mechanism against herbivore attack. This study examined the effects of arsenic exposure (0, 5, 15 and 30 mg kg^?1) on scale insect (Saissetia neglecta) infestation of P. vittata. Scale insects were counted as a percentage fallen from the plant to the total number of insects after 1 week of As-treatment. The arsenic concentrations in the fronds ranged from 5.40 to 812 mg kg^?1. Greater arsenic concentrations resulted in higher percentage of fallen-scale insects (17.2–55.0%). Lower arsenic concentrations (≤5 mg kg^?1) showed significantly lower effect on the population compared to 15–30 mg kg^?1 (p < 0.05). Arsenic content in the fallen-scale insects was as high as 194 mg kg^?1, which indicated that arsenic has been ingested by the scale insects via plant sap. This study is consistent with the hypothesis that arsenic may help P. vittata defend against herbivore's attack.     

Effect of long-term exposure of mice to 900 MHz GSM radiation on experimental cutaneous candidiasis

Mobile phones communicate with base stations using 900 MHz microwaves. The current study was aimed to survey the effects of long-term 900 MHz microwave exposure of mice on experimentally induced cutaneous candidiasis. Forty inbred, male, BALB/c mice were randomly divided into four groups. Cutaneous lesions with Candida albicans were experimentally induced on the lateral-back skin of the 20 mice. One group of the diseased mice were exposed (6 h per day and 7 d per week) to 900 MHz microwave radiation, while the other groups were not exposed. Two unexposed control groups were also included. The skin lesions were regularly monitored and the live candida cell density was enumerated using the colony-forming unit (CFU) assay. The process was repeated after a one week resting interval. One week later, all mice were challenged through intra tail veins using LD₉₀ dose of C. albicans. Mortality of the mice was recorded and the candida load of the kidney homogenates from died animals was counted. 900 MHz microwave exposed mice had 1.5 day and 3.7 day delays on wound healing in stages two. Live Candida inoculated Wave exposed (LCW) mice also showed higher yeast loads in skin lesions at days 5, 7 and 9 post inoculation. Survival analysis of live candida challenged mice showed the radiation exposed group is prone to death induced by systemic infection and candida enumeration from the kidney homogenates showed radiation exposed animals have had significantly higher yeast load in the tissue. In collection, long-term 900 MHz radiation exposure of mice led to longevity of skin wounds and susceptibility of the animals to systemic challenge and higher incidences of microorganisms in internal tissues.     

Effect of chito-oligosaccharide on the oral absorptions of phenolic acids of Flos Lonicerae extract

Phenolic acids, the main active ingredients in Flos Lonicerae extract possess strong antibacterial, antioxidant and antiviral effects, and their contents was higher largely than that of other ingredients such as flavones, but the absolute bioavailability orally was significantly low, which is significant low influencing clinical efficacies of its oral preparations. In the present study, in vitro Caco-2 cell, in situ single-pass intestinal perfusion and in vivo pharmacokinetics study were performed to investigate the effects of COS on the intestinal absorption of phenolic acids. The pharmacological effects such as antiviral activity improvement by COS were verified by MDCK cell damage inhibition rate after influenza virus propagation. The observations from in vitro Caco-2 cell showed that the absorption of phenolic acids in Flos Lonicerae extract could be improved by COS. Meanwhile, COS at the same low, medium and high concentrations caused a significant, concentration-dependent increase in the P_app-value for phenolic acids compared to the control group (p < 0.05), and was all safe for the Caco-2 cells. The observations from single-pass intestinal perfusion in situ model showed that the intestinal absorption of phenolic acids can be enhanced by COS. Meanwhile, the absorption enhancing effect of phenolic acids might be saturable in different intestine sites. In pharmacokinetics study, COS at dosage of 25 mg/kg improved the bioavailability of phenolic acids in Flos Lonicerae extract to the greatest extent, and was safe for gastrointestine from morphological observation. Besides, treatment with Flos Lonicerae extract with COS at dosage of 25 mg/kg prevented MDCK cell damage upon influenza virus propagation better than that of control. All findings above suggested that COS at dosage of 25 mg/kg might be safe and effective absorption enhancer for improving the bioavailability of phenolic acids and the antiviral activity in vitro in Flos Lonicerae extract.