Grazing of the invasive alga Codium fragile ssp. tomentosoides by the common periwinkle Littorina littorea: Effects of thallus size, age and condition

We examined the potential of herbivory by the common periwinkle Littorina littorea to limit recruitment and vegetative re-growth of the invasive green alga Codium fragile ssp. tomentosoides in a series of manipulative field experiments in tidepools on a wave-exposed rocky shore in Nova Scotia, Canada. Snails were excluded or included from circular plots (14 to 20 cm diameter) with cages to compare growth and survival of C. fragile against procedural (partial cages) or natural (uncaged) control plots. Our results show that L. littorea may restrict growth and survival of C. fragile by grazing new recruits (< 2 cm thallus length), fronds of adult thalli that are bleached and necrotic, and residual holdfasts (< 2 mm thickness) of detached thalli (artificially severed to mimic wave dislodgement). Once recruits grow beyond a critical size (~ 3 cm), or damaged tissues or holdfasts regenerate, grazing of C. fragile by L. littorea appears to be limited and ineffectual. Our experimental results corroborate correlative evidence from previous studies that herbivory by L. littorea limits the abundance of C. fragile in tidepools on the Atlantic coast of Nova Scotia, particularly pools in the high intertidal zone where these snails are abundant. Lower on the shore, littorinid grazing and physical stressors that render algae more vulnerable to grazers (e.g. UV radiation and freezing) are less intensive, and probably have less of a regulatory effect on populations of C. fragile.     

Patterns of adult abundance in Chthamalus stellatus (Poli) and C. montagui Southward (Crustacea: Cirripedia) emerge during late recruitment

The aim of this study was to investigate when adult distribution patterns are established in the barnacles Chthamalus stellatus and C. montagui. Adult ‘zones’ were identified by analysing field counts of both species at mid and upper shore heights. Monthly collections of cyprids, < 1 month old metamorphs and recruits (all metamorphosed individuals older than approximately 1 month) were made for C. stellatus and C. montagui in natural barnacle beds at six shores in SW Ireland. This was carried out over one year in 1996/1997, using a hierarchical sampling design. Abundance of total recruits (0-3 months old) was compared between adult zones after the main settlement season had ended. In addition, scales of variability in 0-3 month recruitment into adult zones were compared between the species at two scales: shores (1000s of metres) and sites within shores (10s of metres). Older recruits of each species, up to 11 months of age, were also compared between adult zones.The majority of settlement (measured as attached cyprids) occurred between August and October 1996. In October, there was no effect of adult zone on the abundance of total (0-3 month) recruitment up to that point in either species. Despite this homogeneity in recruitment between adult zones, significant spatial variation was found in 0-3 month recruits of both species at both of the scales examined. In C. stellatus the amount of variation associated with the larger scale (shore) was more than twice that of sites or of the residual variation (replicates within sites). 0-3 month recruitment in C. montagui was also most variable at the scale of shores but the residual variability (between replicates within site) was of similar magnitude to that of shores. Variability in 0-3 month C. montagui recruitment was relatively low at the scale of sites.There was a small but consistent input of recruits to adult zones over 9 months of the year, complicating the assessment of when adult patterns were set-up in these species. By June 1997, characteristic patterns of adult dominance had been established at all shores. Settlement had completely ceased by this time and individual barnacles were potentially 11 months old. Neither settlement nor early recruitment are significant in determining adult zonation patterns in these species. Instead, differential mortality patterns in individuals up to the age of 11 months are implicated in determining patterns of distribution of both species.     

Population dynamics of the green-lipped mussel, Perna canaliculus, at various spatial and temporal scales in northern New Zealand

Ecological processes that differentiate and maintain intertidal populations of mussels, Perna canaliculus, were studied within three sites at Ninety Mile Beach, northern New Zealand. At these three sites (Scott Point, The Bluff and Tonatona Beach), the dynamics of larval availability, primary and secondary settlement, recruitment and mortality rates were investigated at various spatial and temporal scales. (1) Mussel concentrations in seawater were variable with respect to study site and time of year, with highest abundances at the northernmost population (Scott Point) and lowest concentrations at the middle population (The Bluff). In seawater at all three sites, small mussels (< 0.25 mm in shell length) were more abundant in August 2000, while larger mussels (> 0.5 mm in shell length) were more abundant in March 2001. (2) Primary and secondary settlement patterns were investigated during short-term (daily) and long-term (monthly) settlement experiments, within quadrats that were cleared of all mussels in both the mussel bed and in adjacent algal band habitats. At all sites, primary settlement (< 0.5 mm in shell length) was high within the algal band habitat in August 1999, 2000 and 2001. Conversely, secondary settlement (> 2.0 mm in shell length) was high within cleared areas in the mussel beds in November-March 1999-2000 and 2000-2001. Abundance of mussels settling on artificial substrates placed in the intertidal did not differ greatly from comparable areas of natural substrates (bare rock or algae within cleared quadrats). (3) Recruitment and mortality rates were recorded during monthly surveys of the adult populations. Within three mussel size classes (< 24, 25-74 and > 75 mm in shell length), peak recruitment coincided with high mortality in August of the 2 years studied. However, the most dramatic turnover of the population was observed at Scott Point in both years, following a spawning event. In adjacent waters at Scott Point, large accumulations of drift algae covered (up to 100% cover) with juvenile mussels may deplete food supplies usually delivered to intertidal adult mussels, causing their demise. Mats of adult mussels were observed “peeling-off” from the rocky shore at this time of the year, making space available to the new recruits. Where nearshore algal accumulations were moderate to low, only moderate to low mussel turnovers were observed (e.g. Tonatona Beach and The Bluff).     

Population biology of the intertidal kelp, Alaria marginata Postels and Ruprecht: A non-fugitive annual

Persistence of annual plant populations requires sufficient seeds and suitable habitat for development and growth each year. Competition with perennials may prevent within site persistence and result in “fugitive” annual populations. Comparisons have been made between the population biology of annual macroalgae and terrestrial plants, but demographic information necessary to make strong comparisons is lacking for most of these algae, and life history differences may make such comparisons questionable. We studied population dynamics of the kelp Alaria marginata to determine if it was an annual and, if so, how populations persisted. This kelp is the dominant macroalga on exposed mid to low rocky intertidal shores along the Big Sur coast of California. Experimental clearings at two sites were used to assess recruitment timing and survivorship. Sporophytes were collected monthly to determine growth and fecundity. Recruitment occurred in late winter to early spring, primarily on geniculate corallines and residual A. marginata holdfasts. Thinning was inversely related to density, and occurred during the February through July growing season as larger thalli rapidly increased in length (up to 1.4 m month^− 1) and formed a thick canopy. Sorus development was positively related to size, began as early as March, peaked in late August-October, and decreased as adults were removed by winter surf. Spore release was generally highest (10⁸-10⁹ spores individual^− 11 h^− 1) between October and January and associated with high water motion. Survivorship of sporophytes beyond one year was < 1%, showing the populations were annual.Field observations and experiments on effects of canopy clearing, season of clearing, and influence of substrate type on recruitment were done to assess how these annual populations persist. Massive spore production at the onset of fall storms, survival of microscopic stages for 3-4 months facilitated by microhabitat refuges, rapid growth, large size and rapid maturation of sporophytes contributed to persistence. Furthermore, the dense stands with thick canopies may suppress potential competitors via shading and abrasion. Rather than being a fugitive, this combination of growth and life history features enables A. marginata and perhaps other large, annual kelps to maintain perennial populations.     

Spatio-temporal variability of coral recruitment on shallow reefs in St. John, US Virgin Islands

In this study, coral recruitment was measured on a kilometer-wide scale over two years on shallow (5-6 m depth) fringing reefs in St. John, US Virgin Islands, with the objective of determining the extent to which variation in recruitment was affected by biophysical coupling involving temperature and flow. Coral recruitment was measured using settlement tiles deployed at 10 sites along 10 km of shore. The tiles were first deployed in August 2006, and thereafter replaced every ≈ 6 months to sample from either August to January, or January to August over 2 years. Seawater temperature was recorded at the 10 sites using logging thermistors, and flow was quantified using drogues. Overall, corals recruited at a rate equivalent to 76 corals m^− 2 6 months^− 1, and were represented mostly by poritids (43% of recruits), agaricids (29%), faviids (17%) and siderastreids (7%). Although the density of recruits differed among sites in a pattern that varied among periods and years, there was a consistent trend for mean density to decline from ≈ 4 corals tile^− 1 at eastern sites, to ≤ 1 coral tile^− 1 at western sites. One aspect of seawater temperature - the daily range - differed among sites and was greater at western compared to eastern sites, and while it was related inversely to recruitment over one of the sampling periods, it was equivocal as a physical process affecting recruitment. Instead, our results are consistent with biophysical coupling involving patch depletion and downstream filtering, whereby patches of coral larvae are delivered to the south shore of St. John and depleted of larvae through settlement as the water progresses westward.     

Temporal scales of variation in settlement and recruitment of the mussel Perna perna (Linnaeus, 1758)

Population dynamics of many intertidal organisms are strongly affected by the abundance and distribution of larvae arriving on the shore. In particular, not only absolute numbers of settlers but also the degree of synchronisation of settlement can have a strong influence on whether density-dependent or density-independent processes shape adult shape populations. Temporal variation in rates of settlement and recruitment of the mussel Perna perna on the south coast of South Africa was investigated using a nested spatial design at different temporal scales. Variability in settlement at spring tides was examined at two temporal scales: lunar (to investigate the effect of state of the moon on settlement) and tidal (to investigate the influence of state of the tide on mussel settlement). Recruitment over neap tides was examined at one temporal scale, fortnight (to investigate the effect of date on mussel recruitment).Strong temporal variation was evident for both settlement and recruitment, but not at all time scales. Distinct peaks of settler/recruit abundance were observed during the lunar and neap tide studies. Recruitment intensity differed over the course of the year, and pulsing of recruitment was generally synchronised among locations. However, the strength of pulsing differed dramatically among locations, giving a significant interaction between fortnight and location. The finest temporal scale, investigated in the tidal study, did not reveal a significant effect of the state of the tide on settlement. The state of the moon (new or full) was not significant as a main factor (p = 0.052), although generally more settlers arrived on the shore during new moon. Phase of the moon appeared to have an effect on settler abundances, but only when and where densities were high.     

Decolorization of indigo carmine by laccase displayed on Bacillus subtilis spores

Blue multicopper oxidases, laccases displayed on the surface of Bacillus spores were used to decolorize a widely used textile dyestuff, indigo carmine. The laccase-encoding gene of Bacillus subtilis, cotA, was cloned and expressed in B. subtilis DB104, and the expressed enzyme was spontaneously localized on Bacillus spores. B. subtilis spores expressing laccase exhibited maximal activity for the oxidation of 2,2′-azino-bis (3-ethylthiazoline-6-sulfonate) (ABTS) at pH 4.0 and 80 °C, and for the decolorization of indigo carmine at pH 8.0 and 60 °C. The displayed enzyme retained 80% of its original activity after pre-treatment with organic solvents such as 50% acetonitrile and n-hexane for 2 h at 37 °C. The apparent K_m of the enzyme displayed on spores was 443 ± 124 μM for ABTS with a V_max of 150 ± 16 U/mg spores. Notably, 1 mg of spores displaying B. subtilis laccase (3.4 × 10² U for ABTS as a substrate) decolorized 44.6 μg indigo carmine in 2 h. The spore reactor (0.5 g of spores corresponding to 1.7 × 10⁵ U in 50 mL) in a consecutive batch recycling mode decolorized 223 mg indigo carmine/L to completion within 42 h at pH 8.0 and 60 °C. These results suggest that laccase displayed on B. subtilis spores can serve as a powerful environmental tool for the treatment of textile dye effluent.     

Recruitment of the infaunal bivalve Soletellina alba (Lamarck, 1818) (Bivalvia: Psammobiidae) in response to different sediment types and water depths within the intermittently open Hopkins River estuary

Studies examining recruitment processes for soft-sediment macroinvertebrate fauna in intermittent estuaries are rare and most studies of active habitat selection have been tested in the laboratory rather than the field. The present field study examined whether recruitment of the infaunal bivalve Soletellina alba was influenced by water depth and sediment particle size in the intermittent Hopkins River estuary, southern Australia. The number of recruits in sediment trays differed between water depths, but active habitat selection was not evident across treatments of varying sediment particle size. The use of sediments with varying particle sizes also provided an opportunity to identify potential discontinuities in body-size distributions of recruits associated with varying habitat architecture. The length (mm) of recruits was converted to the same scale used to express sediment particle size (i.e. phi units: ? = − log₂ of sediment particle size). The size of recruits differed across water depths, but did not differ across treatments with fine (? = 3) versus coarse (? = 1) sediment, and no relationships were apparent between bivalve size and sediments consisting of varying particle size. These patterns of recruitment do not correspond with the distribution of adult S. alba within the Hopkins River estuary. Previous sampling has shown that abundances of juvenile and adult S. alba are variable across time, site and water depth, but are often greater at the deeper water depth (1.05 m below the Australian Height Datum). However, recruitment during the present study was greatest at the shallower water depth (0.05 m below AHD), and the apparent absence of active habitat selection suggests that the distribution of adults is unlikely to be attributable to differences in recruitment associated with sediments of varying particle size.     

Kneallhazia carolinensae sp. nov., a microsporidian pathogen of the thief ant, Solenopsis carolinensis

A new species of microsporidia is described from adults of the thief ant, Solenopsis carolinensis, collected in Florida, USA. Morphological and genetic characterization of this new species showed that it is most closely related to the genus Kneallhazia and is therefore formally designated, Kneallhazia carolinensae sp. nov. Masses of ovoid, binucleate spores were localized to fat body of adult workers and measured 6.2 ± 0.1 × 3.1 ± 0.1 μm (fresh) and 6.0 ± 0.1 × 3.4 ± 0.1 μm (fixed). These spores were in direct contact with the cell cytoplasm and contained an isofilar polar filament with 12-15 coils. Blastn analysis revealed that the K. carolinensae 16S rDNA sequence exhibited 91% identity with the 16S rDNA gene of K. solenopsae. The morphological and sequence data support the conclusion that K. carolinensae is a novel microsporidian species distinct from K. solenopsae.     

Effect of desiccation level and storage temperature on green spore viability of Osmunda japonica

In order to effectively preserve green spores, which have relatively higher water content and lose viability more quickly than non-green spores, we studied the effect of desiccation level and storage temperature on Osmunda japonica spores. The water content of fresh spores was 11.20%. After 12 h desiccation by silica gel, the water content decreased to 6% but spore viability did not change significantly. As the desiccation continued, the decrease in water content slowed, but spore viability dropped. For almost all storage periods, the effects of storage temperature, desiccation level, and temperature × desiccation level were significantly different. After seven days of storage, spores at any desiccation level stored at 4 °C obtained high germination rates. After more than seven days storage, liquid nitrogen (LN) storage obtained the best results. Storage at −18 °C led to the lowest germination rates. Spores stored at room temperature and −18 °C all died within three months. For storage at 4 °C and in LN, spores desiccated 12 and 36 h obtained better results. Spores without desiccation had the highest germination rates after being stored at room temperature, but suffered the greatest loss after storage at −18 °C. These results suggest that LN storage is the best method of long-term storage of O. japonica spores. The critical water content of O. japonica spores is about 6% and reduction of the water content to this level improves outcome after LN storage greatly. The reason for various responses of O. japonica spores to desiccation and storage temperatures are discussed.     

Sample-to-SNP kit: A reliable,easy and fast tool for the detection of HFE p.H63D and p.C282Y variations associated to hereditary hemochromatosis

Classical hereditary hemochromatosis involves the HFE-gene and diagnostic analysis of the DNA variants HFE p.C282Y (c.845G > A; rs1800562) and HFE p.H63D (c.187C > G; rs1799945). The affected protein alters the iron homeostasis resulting in iron overload in various tissues. The aim of this study was to validate the TaqMan-based Sample-to-SNP protocol for the analysis of the HFE-p.C282Y and p.H63D variants with regard to accuracy, usefulness and reproducibility compared to an existing SNP protocol. The Sample-to-SNP protocol uses an approach where the DNA template is made accessible from a cell lysate followed by TaqMan analysis. Besides the HFE-SNPs other eight SNPs were used as well. These SNPs were: Coagulation factor II-gene F2 c.20210G > A, Coagulation factor V-gene F5 p.R506Q (c.1517G > A; rs121917732), Mitochondria SNP: mt7028 G > A, Mitochondria SNP: mt12308 A > G, Proprotein convertase subtilisin/kexin type 9-gene PCSK9 p.R46L (c.137G > T), Plutathione S-transferase pi 1-gene GSTP1 p.I105V (c313A > G; rs1695), LXR g.-171 A > G, ZNF202 g.-118 G > T. In conclusion the Sample-to-SNP kit proved to be an accurate, reliable, robust, easy to use and rapid TaqMan-based SNP detection protocol, which could be quickly implemented in a routine diagnostic or research facility.     

Spatio-temporal heterogeneity in coral recruitment around Moorea, French Polynesia: Implications for population maintenance

The spatio-temporal variability of scleractinian coral recruitment was investigated from December 2000 to December 2003 around Moorea Island (French Polynesia). Nine stations, each with 20 terracotta tiles, were placed on the outer reef slope, at 3 sites (Vaipahu, Tiahura, Haapiti), and at 3 depths (6, 12 and 18 m). The relative contribution of the different families of recruits (Pocilloporidae: 60.4%, Poritidae: 18.8%, Acroporidae: 11.2%) and the very low recruitment rates (maximum: 35 recruits per tile, higher mean densities of 10.8 recruits per tile, average 40.77 recruits m^− 2 year^− 1) recorded at Moorea are similar to recruitment patterns recorded on sub-tropical reefs. Over the duration of the study period, we detected a marked seasonal variability in recruitment rates, with the peak recruitment for all families recorded in December-March periods, corresponding to periods of warmest SSTs. However, recruits of Acroporidae were also relatively abundant in the September-December period in some years, which coincides with the known spawning periods of some Acropora species. Total recruitment rate decreased after the first year of the survey, and was probably the result of the bleaching event that occurred in early 2002, which may have reduced fecundity of some coral populations. A lower proportion of recruits were found on the upper surface of the tiles (14.5%), compared to the lower surfaces (57.1%) and sides (28.4%), which is likely the result of intense grazing by herbivorous fish and urchins. We detected a patchy distribution at the station scale, and a significant variation in recruitment patterns among depths and sites. Pocilloporidae recruited more abundantly at 6 and 18 m, whereas Poritidae were generally more abundant at 12 m depth. In contrast, Acroporidae showed no clear depth pattern during the study period. Recruitment was lowest at the most exposed site (Haapiti), especially for Acroporidae, and probably reflects lower settlement rates and/or higher early post-settlement mortality caused by frequent high swells and their associated strong currents. These distinctive characteristics in recruitment patterns of the 3 dominant families of recruits underline the important role of life history strategies in understanding the spatial patterns, dynamics and maintenance processes of coral populations. The relatively low coral recruitment rates recorded from this study indicate that recovery from severe or frequent perturbations will be slow.     

Effects of wave exposure on population and reproductive phenology of an algal turf, Gelidium pusillum (Gelidales,Rhodophyta), Songkhla,Thailand

The effect of wave exposure on the population and reproductive phenology of the common red alga, Gelidium pusillum (Stackhouse) Le Jolis, was investigated between July 2003 and June 2004, at Suan Song Tha Le, Songkla Province, Thailand. Lengths of thalli, percentage cover, percentage of reproductive fronds and the number of reproductive structures were examined monthly in relation to different degrees of wave exposure (sheltered vs. exposed), temperature, rainfall, day length and tidal cycles. Frond length and percentage cover of G. pusillum were different among sites and seasons. Shorter fronds were found on the exposed shore which had a greater percentage cover. Fronds bleached and died off during the summer months (April and May), which resulted in shorter fronds and reduced percentage cover in June. The thalli reproduced throughout the year, with a predominance of tetrasporophytes. The highest percentage of tetrasporic fronds was 33% in February 2004 and 13% of cystocarpic fronds in April 2004, but male gametophytic fronds were never observed. Rainfall showed a strongly negative influence on reproduction since no reproductive fronds were observed during the rainy season (R² = 0.49, P = 0.01). The dominance of G. pusillum at this study site and throughout elsewhere in turf habitats might be a function of persistent vegetative growth, densely clumped, and the ability to reproduce almost throughout the entire year.     

Genetic detection and quantification of Nosema apis and N. ceranae in the honey bee

The incidence of nosemosis has increased in recent years due to an emerging infestation of Nosema ceranae in managed honey bee populations in much of the world. A real-time PCR assay was developed to facilitate detection and quantification of both Nosema apis and N. ceranae in both single bee and pooled samples. The assay is a multiplexed reaction in which both species are detected and quantified in a single reaction. The assay is highly sensitive and can detect single copies of the target sequence. Real-time PCR results were calibrated to spore counts generated by standard microscopy procedures. The assay was used to assess bees from commercial apiaries sampled in November 2008 and March 2009. Bees from each colony were pooled. A large amount of variation among colonies was evident, signifying the need to examine large numbers of colonies. Due to sampling constraints, a subset of colonies (from five apiaries) was sampled in both seasons. In November, N. apis levels were 1212 ± 148 spores/bee and N. ceranae levels were 51,073 ± 31,155 spores/bee. In March, no N. apis was detected, N. ceranae levels were 11,824 ± 6304 spores/bee. Changes in N. ceranae levels were evident among apiaries, some increasing and other decreasing. This demonstrates the need for thorough sampling of apiaries and the need for a rapid test for both detection and quantification of both Nosema spp. This assay provides the opportunity for detailed study of disease resistance, infection kinetics, and improvement of disease management practices for honey bees.     

Morphology and taxonomy of the microsporidium Liebermannia covasacrae n. sp. from the grasshopper Covasacris pallidinota (Orthoptera, Acrididae)

During a survey for grasshopper pathogens in Argentina in 2005-2006, individual Covasacris pallidinota from halophylous grasslands in Laprida, Buenos Aires province were found to be infected with a microsporidium. Infection was restricted to the salivary gland epithelial cells. The microsporidium produced ovocylindrical spores averaging 2.6 ± 0.28 × 1.4 ± 0.12 μm (range 2.2-3.4 × 1.1-1.7 μm), which resembled in size and shape the spores of Liebermannia patagonica and L. dichroplusae, two recently described species that also parasitize Argentine grasshoppers. The life cycle of the microsporidium included the formation of polynucleate, diplokaryotic, moniliform, merogonial plasmodia wrapped in flattened cisterns of the host endoplasmic reticulum (ER). Plasmodia divided to produce diplokaryotic cells. The latter underwent elongation, dissociation of diplokarya counterparts, vacuolization, dismantling of the host ER envelope, and deposition of electron-dense material outside the plasma membrane. The resultant binucleate sporogonial plasmodia divided into two uninucleate sporoblasts, which eventually transformed into spores. Uninucleate spores contained a lamellar polaroplast, embraced by an elongated polar sac, anchoring disc, 3-5 polar filament coils, and a cluster of anastomizing tubules (sporoblast trans-Golgi, posterosome) at the posterior end. Sequence similarity of the SSU rDNA of the newly discovered microsporidium (Genbank accession no. EU709818) to L. patagonica and L. dichroplusae was 99% and 97%, respectively, suggesting that the three species belong to one genus. All three species fell into one clade in SSU rDNA-based phylogenetic trees produced by neighbor joining, maximum parsimony, and maximum likelihood analyses with 100% statistical support. We assign the name Liebermannia covasacrae to this microsporidium. It can be easily differentiated from both congeners by host species, tissue tropism, type of sporogony, and several features of morphology. Comparison of the three Liebermannia spp. demonstrates that the nuclear phase (dikaryotic versus monokaryotic spores) and type of sporogony (polysporous versus disporous) may vary in closely related species.     

Ecological status of the Mediterranean Juniperus phoenicea L. Relicts in the desert mountains of North Sinai,Egypt

Juniperus phoenicea L. is listed as threatened tree by IUCN Red List. In Egypt, J. phoenicea L. is the only conifer tree that is restricted to the three mountains of northern Sinai: Gabal El-Halal, Gabal El-Maghara and Gabal Yelleq. As a Mediterranean relict it has been included in a national list as target for conservation and management. To provide baseline information for the development of a conservation strategy, the present study aims at comparing the isolated populations of J. phoenicea and their associated plant composition and diversity at the three mountains. The application of TWINSPAN and DCA analysis techniques has resulted in identifying of four vegetation types associated with juniper, and each could be related to a specific geomorphologic habitat on a topographic gradient. Chiliadenus montanus and Zygophyllum dumosum characterized the slopes of smooth-faced rock outcrops in Wadi Abu Seyal (at 350–470 m altitude of Gabal El-Halal), Deverra tortuosa, Ephedra aphylla and Gymnocarpos decander inhabited together with the target species the soil pockets of north-facing slope in Neqeb Abu Hamam (at 600–700 m altitude of Gabal El-Halal), Stachys aegyptiaca and Moricandia nitens characterized the juniper occurrences in the runnels of Wadi Arar (at 450–560 m altitude of Gabal El-Maghara), and Artemisia herba-alba, Atriplex halimus and Reaumuria hirtella represent the stands on slope runnels (at 900–960 m) of Gabal Yelleq. The two vegetation types recognized at Gabal El-Halal had, on average, the highest species diversity, juniper density and cover. Juniper shows generally poor conditions of vitality at higher elevation (600–960 m) with a higher proportions of old and recent dead trees, and with the predominance of male individuals, as compared with the populations of Gabal El-Maghara and Gabal Yelleq. In contrast, the juniper populations at lower elevation (350–470 m) of Gabal El-Halal proved to be in best condition with mostly living foliage and reproductive branches. The differences in rock types and elevation among the three mountains reflect serious limitation on recruitment of J. phoenicea due to moisture availability. The results of this study showed that J. phoenicea is an endangered species and its conservation in northern Sinai mountains is a priority. For a successful conservation of this community it is highly recommended to preserve in particular the suitable habitats at Gabal El-Halal, but also the other stands merit conservation measures.     

Identification of bovine NPC1 gene cSNPs and their effects on body size traits of Qinchuan cattle

NPC1 gene is an important gene closely related to the Niemann–Pick type C (NPC). Mutations in the NPC1 gene tend to cause Niemann–Pick type C, a lysosomal storage disorder. Previous studies have shown that NPC1 protein plays an important role in subcellular lipid transport, homeostasis, platelet function and formation, which are basic metabolic activities in the process of development. In this study, to explore the association between the NPC1 gene variation and body size traits in Qinchuan cattle, we detected four novel coding single nucleotide polymorphisms (cSNPs) in the bovine NPC1 gene, including one missense mutation (SNP1) and three synonymous mutations (SNP2, SNP3 and SNP4). Population genetic analyses of 518 individuals and association correlations between cSNPs and bovine body size traits were conducted in this research. A missense mutation at SNP1 locus was found to be significantly related to the heart girth, hip width and body weight (P < 0.01 or P < 0.05, 3.5-year-old). Two synonymous mutations at SNP2 and SNP3 loci also showed significant effects on hip width (P < 0.05, 3.5-year-old). One synonymous mutation at SNP4 locus showed significant effect on body weight (P < 0.05, 2.0-year-old). Combined haplotypes H₂H₆ and H₆H₆ showed significant effects on body size traits such as heart girth, hip width, and body weight (3.5-year-old, P < 0.01 or P < 0.05). This study provides evidence that the NPC1 gene might be involved in the regulation of bovine growth and body development, and may be considered as a candidate gene for marker assisted selection (MAS) in beef cattle breeding industry.     

A CLCNKA polymorphism (rs10927887; p.Arg83Gly) previously linked to heart failure is associated with the estimated glomerular filtration rate in the RENASTUR cohort

A total of 569 individuals aged 55–85 and Caucasian were genotyped for SNP rs10927887 in the K_a renal chloride channel gene (CLCNKA). The following variables were significantly associated with an estimated glomerular filtration rate of (eGFR) < 60 ml/min./1.73 m²: age, type 2 diabetes, total cholesterol, LDL-cholesterol, and the CLCNKA GG genotype (p = 0.03; OR = 1.65, 95% CI = 1.04–2.62). This novel finding could partly explain the reported greater risk of heart failure linked to the CLCNKA SNP, but requires confirmation on other populations.     

Temperature limits to early development of the New Zealand sea urchin Evechinus chloroticus (Valenciennes, 1846)

Seawater temperature is an important environmental factor for the early life stages of marine invertebrates. In this study we evaluated and described the effects of temperature during early development of E. chloroticus, identifying the optimum temperature range and upper thermal limit for successful development. The temperature range evaluated was between 15–24 °C which included the normal seawater temperatures during the spawning season in northern New Zealand, as well as the highest temperature projected by the IPCC for this region due to global warming (1–3 °C by the year 2100). Gametes from several females and males were used in the experiment. Fertilization was carried out at different temperatures and development was monitored at different time points after fertilization in each temperature. The development rate of E. chloroticus increased with an increase in seawater temperature. However, at temperatures higher than 21.5 °C the amount of abnormal development reached ∼30%. The optimum temperature for early development was between 15–21 °C, whereas the upper thermal limit was ∼24 °C. Therefore, early development of E. chloroticus is negatively affected by an increase in seawater temperature of ∼3–4 °C above current seawater temperature levels in northern New Zealand. The thermal sensitivity of early life stages of E. chloroticus could affect survival rates during early development of this species in a global warming scenario, which could impair recruitment in populations which are exposed to higher temperatures, leading to possible distributional shifts of this species.     

Genetic diversity and biogeography of the traditional Chinese medicine, Gardenia jasminoides, based on AFLP markers

Gardenia jasminoides Ellis is used in traditional Chinese medicine (TCM) in China. Levels of genetic variation and patterns of population structure within and among eight wild or cultivated populations of G. jasminoides Ellis in China were investigated using amplified fragment length polymorphism (AFLP) markers. Of the 11 primers screened, four produced highly reproducible AFLP bands. Using these primers, 244 discernible DNA fragments were generated with 165 bands (67.6%), were polymorphic, indicating considerable genetic variation at the species level. In contrast, there were relatively low levels of polymorphism at the population level with the percentage of polymorphic bands (PPB) ranging from 36.89% to 59.43%. Genetic diversity within populations ranged from 0.2086 to 0.3108, averaging 0.2392 at the species level. A high level of genetic differentiation among populations was detected based on Nei's genetic diversity analysis (76.59%), Shannon's index analysis (64.8%) and AMOVA analysis (72.75%). No significant statistical differences (analysis of molecular variance [AMOVA], p = 0.0639) in AFLP variation were found between regions. However, the variance among populations and within populations differed significantly (p < 0.001). An indirect estimate of historical levels of gene flow (N_m = 1.7448) was consistent with the high mean genetic identity (mean I = 0.9263) found among populations. There is an association between geographic and genetic distances between populations. Presently gene change exists between populations.