The larval reticulum in Phyllodoce (Polychaeta,Phyllodocida)

Summary Phyllodoce trochophores have a system of large, multipolar, nerve-like cells similar to the larval reticulum of the much-studied larva of Lopadorhynchus. The Phyllodoce reticulum is described here by means of light and electron microscopy and Golgi-Cox preparations. The cells appear to be secretory, and contain numerous large vesicles approximately 1 m in diameter. Their nuclei are large and distinctive, with a dense, granular nucleoplasm containing unusual hollow tubules, 40 nm in diameter, arranged in tangled masses and parallel arrays. The cells are nerve-like in that they possess surface processes that ramify irregularly throughout the larval tissues and thinner, basal processes that run along the larval nerves. They differentiate in close association with nerve cells of conventional type, the principal centres being in the apical region, on either side of the apical organ, and in the oral region, on either side of the mouth. The latter are centres of nerve differentiation in species with a metatroch. Phyllodoce larvae lack a metatroch, but the band itself could have been lost secondarily during evolution without loss of the neural elements associated with it. The precise function of the reticular system is not known. Basal processes connect it to the larval nerves, suggesting its cells receive neural input and, presumably, release their secretion from surface processes. There is no obvious evidence of secretory release during the larval phase, but the system disappears entirely at metamorphosis, suggesting a role in this process, possibly related to the histolysis of larval tissues.     

Clarification of the genetic component of hybrids between Phyllodoce caerulea and Phyllodoce aleutica (Ericaceae) in Hokkaido,northern Japan

Natural hybridization provides great opportunities to understand the interaction of genetics and ecology in determining species boundaries. We examined the genetic relationships of Phyllodoce taxa and revealed that most hybrids were fertile F₁s and an extremely small number of backcross and no F₂ plants were established in natural conditions. Because this trend was irrespective of regions, we conclude that negative endogenous selection may act after the germination of F₁ seeds and prevent the establishment of later‐generation hybrids. Based on these results, we discuss the ecological and evolutionary significance of natural hybridization in Phyllodoce taxa.     

A hybrid zone dominated by fertile F1s of two alpine shrub species, Phyllodoce caerulea and Phyllodoce aleutica, along a snowmelt gradient

In alpine ecosystems, the steep environmental gradients produced by the difference in snowmelt timing create a dynamic selective regime for alpine plants. As these gradients directly alter flowering phenology, they can affect pollen-mediated gene flow among populations of single and related species. In northern Japan, we found a hybrid zone dominated by fertile F(1)s of two alpine shrub species, Phyllodoce caerulea and P. aleutica, along a snowmelt gradient. Seed germination confirmed the fertility of F(1) hybrid, making the rarity and absence of backcross and F(2) plants puzzling. The long-term clonal perpetuation of F(1) hybrids (at least a few thousand years ago) contributes the maintenance of this unique hybrid zone. The distribution patterns of chloroplast DNA haplotypes suggest that F(1) formation might be caused by directional pollen flow between parental species along the snowmelt gradient. Based on these results, we discuss the ecological and evolutionary significance of this unique hybrid zone.     

A New Species of Phyllodoce (Ericaceae) from China

In the present paper, one new species of the genus Phyllodoce (Ericace-ae) is described from China. It is Phyllodoce deflexa Ching ex H. P. Yang.     

Novel, posterior sensory organ in the trochophore larva of Phyllodoce maculata (Polychaeta)

A new posterior sensory organ (PSO), located at the dorsal midline of the hyposphere, is described by immunocytochemical detection of acetylated alpha tubulin and serotonin (5-HT) in a laser-scanning microscope, as well as three-dimensional reconstructions after optical serial sectioning in the trochophore larva of the polychaete Phyllodoce maculata (Phyllodocidae). The unpaired PSO consists of five bipolar sensory cells, two of them being 5-HT immunopositive, which send axons to the cerebral ganglion and prototroch nerve. The dendrites of these cells project to the surface and bear one cilium each. A single neuronal fibre from the apical sensory organ innervates the PSO.     

Phylogeography and refugia of the Japanese endemic alpine plant, Phyllodoce nipponica Makino (Ericaceae)

Aim  This study aims to elucidate the phylogeography of the Japanese endemic alpine plant, Phyllodoce nipponica Makino (Ericaceae) and to infer the location of refugia of alpine plants in Japan during climatic oscillations.
Location  Alpine zone in the Japanese archipelago.
Methods  We determined the chloroplast (cp) DNA haplotypes of 155 individuals (22 populations) based on sequence data from the trnL-F and trnT-L intergenic spacers and the trnL intron, whose phylogenetic relationships were analysed using the program tcs . To examine the genetic structure, analysis of molecular variance ( amova ) was carried out and the population differentiation was shown by the parameters G _ST and N _ST.
Results  The haplotype composition and the results of amova showed that populations in the Japanese Central Mountain Region (JCMR) and in the westernmost region were highly divergent (18.8%). The diversity within populations was very high in the JCMR ( h _S = 0.421); less variation was found within populations located in other regions at lower elevations.
Main conclusions  Phyllodoce nipponica survived climatic changes during the Quaternary in the JCMR and the westernmost region. Most of the distribution range was colonized during only one range expansion. The source location from which the range expansion occurred was unclear.     

Variations in bumble bee preference and pollen limitation among neighboring populations: comparisons between Phyllodoce caerulea and Phyllodoce aleutica (Ericaceae) along snowmelt gradients

Two alpine-snowbed shrubs, Phyllodoce caerulea and P. aleutica (Ericaceae), co-occur in locales in northern Japan with early to late snowmelt, but they have different mating systems. Phyllodoce caerulea is an obligate outcrosser in any population, whereas the selfing ability of P. aleutica is highly variable among neighboring populations along snowmelt gradients: it shows high self-compatibility in early to middle snowmelt populations but low self-compatibility in late snowmelt populations. We investigated the relationships between pollinator availability and mating systems of these species along three snowmelt gradients. Relative abundance of flowers and nectar standing crop of P. caerulea decreased from early to late snowmelt plots. Bumble bees preferred P. caerulea to P. aleutica in early and middle snowmelt plots, while their preference shifted to P. aleutica in late snowmelt plots. Pollen limitation was severe in P. aleutica in early to middle snowmelt plots but it was severe in P. caerulea in late snowmelt plots. Seed-set success under natural conditions of P. aleutica was higher than that of P. caerulea in all plots. Thus, we infer that the selfing ability of P. aleutica under pollinator limitation acts as a reproductive assurance. We conclude that the interaction through pollination between the sympatric species is strong enough to cause a phenotypic change in mating system even within a local area.     

Some species of the genus Phyllodoce (Polychaeta) from Southern California

Five species of the genus Phyllodoce from Southern California are reviewed. A new subgenus (Aponaitides) is proposed and a new species, Phyllodoce cuspidata , is described. A key to the Southern California species is included.     

松毛翠的组织培养和快速繁殖

1植物名称 松毛翠（Phyllodo cecaerulea L．Bab．）。 2材料类别 新萌发嫩茎尖。 3培养条件 基本培养基为MS。（1）嫩茎尖愈伤组织诱导培养基：1／3MS＋2-Ip5．0mg·L^-1（单位下同）＋NAA0．5＋3％蔗糖;（2）愈伤组织再分化培养基：1／3MS＋2-Ip4．5＋IAA0．4＋3％蔗糖;（3）芽的继代增殖培养基：1／3MS＋2-Ip3．5＋IAA0．25＋3％蔗糖;     

Eight microsatellite markers for sympatric alpine shrubs,Phyllodoce aleutica and P. caerulea (Ericaceae)

Phyllodoce aleutica and Phyllodoce caerulea are sympatric alpine‐snowbed plants in northern Japan. They compete for pollinators (bumblebees) each other and the competitive situation varies depending on snow conditions. We isolated and characterized eight microsatellite loci in these species. Additionally, one of 13 primers developed for Rhododendron metternichii was available in these species. The expected heterozygosity of these nine markers ranged from 0.06 to 0.93 in P. aleutica and from 0.09 to 0.96 in P. caerulea. These markers may be useful to reveal the mating system evolution, patterns of pollen flow and the process of natural hybridization in these Phyllodoce species.     

Flowering phenology influences seed production and outcrossing rate in populations of an alpine snowbed shrub, Phyllodoce aleutica: effects of pollinators and self-incompatibility

Background and Aims

Because of differences in snowmelt time, the reproductive phenologies of alpine plants are highly variable among local populations, and there is large variation in seed set across populations. Temporal variation in pollinator availability during the season may be a major factor affecting not only seed production but also outcrossing rate of alpine plants.

Methods

Among local populations of Phyllodoce aleutica that experience different snowmelt regimes, flowering phenology, pollinator availability, seed-set rate, and outcrossing rate were compared with reference to the mating system (self-compatibility or heterospecific compatibility with a co-occurring congeneric species).

Key Results

Flowering occurred sequentially among populations reflecting snowmelt time from mid-July to late August. The visit frequency of bumble-bees increased substantially in late July when workers appeared. Both seed set and outcrossing rate increased as flowering season progressed. Although flowers were self-compatible and heterospecific compatible, the mixed-pollination experiment revealed that fertilization with conspecific, outcrossing pollen took priority over selfing and hybridization, indicating a cryptic self-incompatibility. In early snowmelt populations, seed production was pollen-limited and autogamous selfing was common. However, genetic analyses revealed that selfed progenies did not contribute to the maintenance of populations due to late-acting inbreeding depression.

Conclusions

Large variations in seed-set and outcrossing rates among populations were caused by the timing of pollinator availability during the season and the cryptic self-incompatibility of this species. Despite the intensive pollen limitation in part of the early season, reproductive assurance by autogamous selfing was not evident. Under fluctuating conditions of pollinator availability and flowering structures, P. aleutica maintained the genetic composition by conspecific outcrossing.Key words: Alpine snowbed, autogamy, bumble-bee, cryptic self-incompatibility, flowering phenology, mixed pollination, outcrossing rate, Phyllodoce aleutica, pollination success, seasonality, self-pollination     

Importance of demographic history for phylogeographic inference on the arctic–alpine plant Phyllodoce caerulea in East Asia

Arctic–alpine plants have enormous ranges in the Northern Hemisphere. Phylogeographic studies have provided insights into their glacial survival as well as their postglacial colonization history. However, our understanding of the population dynamics of disjunct alpine populations in temperate regions remains limited. During Pleistocene cold periods, alpine populations of arctic–alpine species in East Asia were either connected to an ice-free Beringia refugium or they persisted with prolonged isolation after their establishment. To estimate which of these scenarios is more likely, we elucidated the genetic structure of Phyllodoce caerulea (Ericaceae) in Beringia and northern Japan, East Asia. Sequence variation in multiple nuclear loci revealed that P. caerulea can be distinguished into northern and southern groups. A demographic analysis demonstrated that the north–south divergence did not predate the last glacial period and detected introgression from Phyllodoce aleutica, relative widely distributed in East Asia, exclusively into the southern group. Therefore, although there has been genetic divergence between northern Japan and Beringia in P. caerulea, the divergence is unlikely to have resulted from their prolonged geographic separation throughout several cycles of glacial and interglacial periods. Instead, our study suggests that the introgression contributed to the genetic divergence of P. caerulea and that the range of P. caerulea was plausibly connected between northern Japan and Beringia during the last glacial period. Overall, our study not only provides a biogeographic insight into alpine populations of arctic–alpine plants in East Asia but also emphasizes the importance of careful interpretation of genetic structure for inferring phylogeographic history.     

A multilocus sequencing approach reveals the cryptic phylogeographical history of Phyllodoce nipponica Makino (Ericaceae)

Discordant phylogeographical patterns among species with similar distributions may not only denote specific biogeographical histories of different species, but also could represent stochastic variance of genealogies in applied genetic markers. A multilocus investigation representing different genomes can be used to address the latter concern, allowing robust inference to biogeographical history. In the present study, we conducted a multilocus phylogeographical analysis to re‐examine the genetic structuring of Phyllodoce nipponica, in which chloroplast (cp)DNA markers exhibited a discordant pattern compared to those of other alpine plants. The geographical structure of sequence variation at five nuclear loci was not consistent with that of cpDNA and showed differentiation between the northern and southern parts of the range of this species. Its demographic history inferred from the isolation‐with‐migration model suggests that the north–south divergence originated from Pleistocene vicariance. In addition, the demographic parameters showed a lack of chloroplast‐specific gene flow, suggesting that stochastic variance in genealogy resulted in the discordant geographical structure. Thus, P. nipponica probably experienced Pleistocene vicariance between its southern and northern range parts in concordance with other alpine plants in the Japanese archipelago. The findings of the present study demonstrates the importance of using a multilocus approach for inferring population dynamics, as well as for reconciling discordant phylogeographical patterns among species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 214–226.     

Sphinctocystis phyllodoces gen. n., sp. n. (Eugregarinida: Lecudinidae)--a new gregarine from Phyllodoce citrina (Polychaeta: Phyllodocidae)

A new species of aseptate gregarine, Sphinctocystis phyllodoces gen. n., sp. n., from the gut of a polychaete Phyllodoce citrina Malmgren, 1865 from White Sea is described. The electron and light microscopic data on trophozoits are presented. Taxonomy of the described species is discussed. Certain ultrastructural characters are included in generic and specific diagnoses. Order Eugregarinida Leger, 1900; suborder Aseptata Chakravarty, 1960; family Lecudinidae Kamm, 1922. GENUS: Sphinctocystis gen. n. TYPE SPECIES: Sphinctocystis phyllodoces sp. n. DIAGNOSIS: Characters of the family. Free trophozoits elongated, often with several annular constrictions. Anterior end asymmetric, without hooks, not separated from the body, with small apical papilla encircled by smooth area. Epicyte "classical", without additional axial formations at the tops of folds; epicytic folds high, monomorphic in cross sections, finger-shaped, with parallel sidewalls. In the gut of polychaetes. DIFFERENTIAL DIAGNOSIS: The new genus differs from Lecudina by having asymmetric anterior end, developed smooth area around the apical papilla, and monomorphic epicytic folds looking finger-shaped in cross sections. It also differs from Lankesteria by the absence of additional axial formations at the tops of the epicytic folds. It differs from both named genera by presence of annular constrictions on the trophozoit body. Sphinctocystis phyllodoces sp. n. DIAGNOSIS: Characters of the genus. Free trophozoits elongated, large, up to 617 x x 77 um. The average height of epicytic folds 976 nm, thickness 194 nm; there are 6-8 apical filaments and rippled dense structures per fold. Nucleus spherical (ellipsoid after fixation), 24-52 microm along longest axis, localised in anterior third of the body, carries several karyosomes of various size; 25-30 nm thick fibrils (possible fragments of nucleolonema) may be present in karyolymph. Other stages unknown. TYPE SERIES: Microscope preparation with 7 trophozoits, Karacci's haematoxylin stained, is kept in the Zoological museum of the Moscow State University (collection number: Z-1). TYPE HOST: Phyllodoce citrina Malmgren, 1865 (Polychaeta: Phyllodocidae). LOCALISATION: Mid-gut. TYPE LOCALITY: White Sea Biological Station of the Moscow State University, Yeremeyevsky Rapid, Velikaya Salma Strait, Kandalaksha Bay, White Sea.     

Crystal structure, detonation performance, and thermal stability of a new polynitro cage compound: 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptacyclo [5.5.1.13, 11. 15, 9] pentadecane

A new polynitro cage compound 2, 4, 6, 8, 10, 12, 13, 14, 15-nonanitro-2, 4, 6, 8, 10, 12, 13, 14, 15-nonaazaheptcyclo [5.5.1.1(3,11).1(5,9)] pentadecane (NNNAHP) was designed in the present work. Its molecular structure was optimized at the B3LYP/6-31 G(d,p) level of density functional theory (DFT) and crystal structure was predicted using the Compass and Dreiding force fields and refined by DFT GGA-RPBE method. The obtained crystal structure of NNNAHP belongs to the P-1 space group and the lattice parameters are a = 9.99 ?, b = 10.78 ?, c = 9.99 ?, α = 90.01°, β = 120.01°, γ = 90.00°, and Z = 2, respectively. Based on the optimized crystal structure, the band gap, density of state, thermodynamic properties, infrared spectrum, strain energy, detonation characteristics, and thermal stability were predicted. Calculation results show that NNNAHP has detonation properties close to those of CL-20 and is a high energy density compound with moderate stability.     

Relations of the Al,B, Ba,Br, Ca,Cl, Cu,Fe, K,Li, Mg,Mn, Na,P, S,Si, Sr,and Zn mass fractions to morphometric parameters in pediatric and nonhyperplastic young adult prostate glands

The variation with age of the 18 trace element mass fractions and some histological characteristics of intact prostate glands of 50 subjects aged 0–30 years was investigated by instrumental neutron activation analysis, inductively coupled plasma atomic emission spectrometry, and a quantitative morphometric analysis. Mean values ± standard error of the mean (M ± SΕΜ) for the mass fractions (in milligrams per kilogram wet tissue) of these trace elements in pre-puberty were: Al 28.5 ± 9.0, B 0.40 ± 0.11, Ba 1.48 ± 0.44, Br 10.5 ± 1.5, Ca 241 ± 30, Cl 3,203 ± 278, Cu 3.51 ± 0.89, Fe 33.7 ± 4.1, K 2,364 ± 145, Li 0.020 ± 0.004, Mg 153 ± 23, Mn 0.46 ± 0.06, Na 2,286 ± 130, P 1,391 ± 100, S 1,698 ± 132, Si 62 ± 11, Sr 0.38 ± 0.08, and Zn 27.6 ± 2.3. During puberty and postpuberty, when there is a significant increase in circulating androgens, the mean values were: Al 7.2 ± 1.4, B 0.21 ± 0.05, Ba 0.25 ± 0.06, Br 5.8 ± 1.0, Ca 433 ± 81, Cl 2,314 ± 201, Cu 1.77 ± 0.13, Fe 20.9 ± 1.6, K 2,585 ± 118, Li 0.0088 ± 0.0014, Mg 232 ± 27, Mn 0.34 ± 0.04, Na 1,875 ± 107, P 1,403 ± 98, S 1,673 ± 73, Si 22.2 ± 3.1, Sr 0.22 ± 0.03, and Zn 93.3 ± 8.9. Mean values (M ± SΕΜ) of percent volumes (%) of the stroma, epithelium and lumen in the prostate before puberty were 73.4 ± 2.6, 20.4 ± 1.7, and 4.45 ± 0.94, respectively, versus 46.5 ± 2.5, 38.5 ± 1.9, and 14.9 ± 1.2 during puberty and postpuberty. This work’s results confirm that the Zn mass fraction in prostate tissue is an androgen-dependent parameter. For the first time it has been demonstrated that the glandular lumen is a main pool of Ca, Mg, and Zn accumulation and that the stroma is a main pool of Al, B, Ba, Br, Cl, Cu, Fe, Mn, Na, and Si accumulation in the normal human prostate, for the age range 0–30 years. It was concluded that the Ca, Mg, and Zn binds tightly within the prostatic fluid, because the volume of glandular lumen reflects the volume of prostatic fluid.