Taxonomic revision of the genus <Emphasis Type="Italic">Catalpa</Emphasis> (Bignoniaceae)

A taxonomic revision of Catalpa (Bignoiaceae), a genus of perennial trees frequently used in horticulture as garden and street trees, is provided. Eight natural species and two hybrid species are recognized, four in sect. Catalpa, four in sect. Macrocatalpa, and two hybrid species in sect. Catalpa. Although C. punctata has been used for one of the tropical species, C. macrocarpa is the correct scientific name. Catalpa tibetica is synonymous with C. bignonioides, C. fargesii with C. bungei, and C. obovata with C. macrocarpa. Lectotypes are designated for: Bignonia cassinoides, Bignonia longisiliqua, Bignonia longissima, Catalpa Walter, Catalpa subsect. Corymbosae, Catalpa bignonioides var. kaempferi, Catalpa bungei, Catalpa bungei var. heterophylla, Catalpa bungei var. intermedia, Catalpa domingensis, Catalpa fargesii, Catalpa henryi, Catalpa ×hybrida, Catalpa ovata var. flavescens, Catalpa punctata var. lepidota, Catalpa purpurea, Catalpa syringifolia var. pulverulenta, Catalpa sutchuensis, Catalpa ×teasii, and Cumbulu. Second-step lectotypes are designated for: Catalpa duclouxii, Catalpa ekmaniana, Catalpa oblongata, Catalpa obovata, and Catalpa ovata. Neotypes are designated for: Bignonia triloba, Catalpa aureovittata, Catalpa bignonioides var. variegata, Catalpa ×erubescens, Catalpa ×erubescens f. purpurea, Catalpa ×galleana, Catalpa ×hybrida var. atropurpurea, Catalpa japonica, Catalpa syringifolia var. aurea, Catalpa syringifolia var. koehnei, Catalpa syringifolia var. nana, Catalpa ×teasiana, and Catalpa umbraculifera.     

First observations of temperature tolerances of adult male snow crab (Chionoecetes opilio) from the Barents Sea population and the effects on the fisheries strategy

This study investigates the effects of temperature on the survival, food intake, oxygen consumption and growth during long-term live holding of captive male snow crab (Chionoecetes opilio) (average?=?0.7?kg). The crabs were held at three different temperatures, 3, 6 and 9°C. The trials were done using groups of snow crabs held in nine land-based holding tanks (three replicates per temperature treatment). The results showed that temperature had a significant effect on survival. The survival rate at 3°C (61%) was significantly higher than at 6°C (33%) and at 9°C (28%). Specific oxygen consumption rates of unfed crab at 6°C were significantly higher than at 9°C and 3°C. In summary, the current study shows that the Barents Sea snow crab have a narrow temperature range in which they thrive compared with the Barents Sea red king crab (Paralithodes camtschaticus). Barents Sea snow crab has similar metabolic and physiological attributes to other major snow crab populations. In conditions when ambient temperatures are approximately 6°C, it may prove beneficial for animal welfare and also be financially advantageous to reduce ambient water temperatures in live snow crab holding facilities on boat or on land.     

All roads lead to weediness: Patterns of genomic divergence reveal extensive recurrent weedy rice origins from South Asian Oryza

Weedy rice (Oryza spp.), a weedy relative of cultivated rice (O. sativa), infests and persists in cultivated rice fields worldwide. Many weedy rice populations have evolved similar adaptive traits, considered part of the ‘agricultural weed syndrome’, making this an ideal model to study the genetic basis of parallel evolution. Understanding parallel evolution hinges on accurate knowledge of the genetic background and origins of existing weedy rice groups. Using population structure analyses of South Asian and US weedy rice, we show that weeds in South Asia have highly heterogeneous genetic backgrounds, with ancestry contributions both from cultivated varieties (aus and indica) and wild rice. Moreover, the two main groups of weedy rice in the USA, which are also related to aus and indica cultivars, constitute a separate origin from that of Asian weeds. Weedy rice populations in South Asia largely converge on presence of red pericarps and awns and on ease of shattering. Genomewide divergence scans between weed groups from the USA and South Asia, and their crop relatives are enriched for loci involved in metabolic processes. Some candidate genes related to iconic weedy traits and competitiveness are highly divergent between some weed‐crop pairs, but are not shared among all weed‐crop comparisons. Our results show that weedy rice is an extreme example of recurrent evolution, and suggest that most populations are evolving their weedy traits through different genetic mechanisms.     

Proteome analysis of peroxisomes from dark-treated senescent Arabidopsis leaves

Peroxisomes compartmentalize a dynamic suite of biochemical reactions and play a central role in plant metabolism, such as the degradation of hydrogen peroxide,metabolism of fatty acids, photorespiration, and the biosynthesis of plant hormones. Plant peroxisomes have been traditionally classified into three major subtypes, and in-depth mass spectrometry(MS)-based proteomics has been performed to explore the proteome of the two major subtypes present in green leaves and etiolated seedlings. Here, we carried out a comprehensive proteome analysis of peroxisomes from Arabidopsis leaves given a 48-h dark treatment.Our goal was to determine the proteome of the third major subtype of plant peroxisomes from senescent leaves, and further catalog the plant peroxisomal proteome. We identifieda total of 111 peroxisomal proteins and verified the peroxisomal localization for six new proteins with potential roles in fatty acid metabolism and stress response by in vivo targeting analysis. Metabolic pathways compartmentalized in the three major subtypes of peroxisomes were also compared, which revealed a higher number of proteins involved in the detoxification of reactive oxygen species in peroxisomes from senescent leaves. Our study takes an important step towards mapping the ful function of plant peroxisomes.     

Methylenedioxy- and methoxyflavones from Melicope coodeana syn. Euodia simplex

Three new natural products, 3,8-dimethoxy-5,7-dihydroxy-3′,4′-methylenedioxyflavone, 3,6,8-trimethoxy-5,7-dihydroxy-3′,4′-methylenedioxyflavone and 3,6,8,3′,4′-pentamethoxy-5,7-dihydroxyflavone were isolated from Melicope coodeana syn. Euodia simplex (Rutaceae) along with 3,6,3′-trimethoxy-5,7,4′-trihydroxyflavone and 3,3′-dimethoxy-5,7,4′-trihydroxyflavone. The structural assignments are based on ¹H and ¹³C NMR data, including discussion of the chemical shifts of C-2 in 3,5-dihydroxy- and 3-methoxy-5-hydroxyflavones. The presence of highly methoxylated and methylenedioxyflavones is characteristic of the genus Melicope, and the present findings support the recent transfer of Euodia simplex to Melicope.     

Prolonged hypobaric hypoxemia attenuates vasopressin secretion and renal response to osmostimulation in men.

Effects of hypobaric hypoxemia on endocrine and renal parameters of body fluid homeostasis were investigated in eight normal men during a sojourn of 8 days at an altitude of 4,559 m. Endocrine and renal responses to an osmotic stimulus (5% hypertonic saline, 3.6 ml/kg over 1 h) were investigated at sea level and on day 6 at altitude. Several days of hypobaric hypoxemia reduced body weight (-2.1 +/- 0.4 kg), increased plasma osmolality (+5.3 +/- 1.4 mosmol/kgH(2)O), elevated blood pressure (+12 +/- 1 mmHg), reduced creatinine clearance (122 +/- 6 to 96 +/- 10 ml/min), inhibited the renin system (19.5 +/- 2.0 to 10.9 +/- 0.9 mU/l) and plasma vasopressin (1.14 +/- 0.16 to 0.38 +/- 0.06 pg/ml), and doubled circulating levels of norepinephrine (103 +/- 16 to 191 +/- 35 pg/ml) and endothelin-1 (3.0 +/- 0.2 to 6.3 +/- 0.6 pg/ml), whereas urodilatin excretion rate decreased from day 2 (all changes P < 0.05 compared with sea level). Plasma arginine vasopressin response and the antidiuretic response to hypertonic saline loading were unchanged, but the natriuretic response was attenuated. In conclusion, chronic hypobaric hypoxemia 1) elevates the set point of plasma osmolality-to-plasma vasopressin relationship, possibly because of concurrent hypertension, thereby causing hypovolemia and hyperosmolality, and 2) blunts the natriuretic response to hypertonic volume expansion, possibly because of elevated circulating levels of norepinephrine and endothelin, reduced urodilatin synthesis, or attenuated inhibition of the renin system.     

Impacts of wet grassland management and winter severity on wader breeding numbers in eastern Denmark

Attempts to reverse the population declines of many wader species in Denmark and other parts of Europe during the last 20–30 years have resulted in the application of several management implements. In this study we evaluate the effect of two management implements (grazing by cattle and winter flooding) on the number of breeding pairs of lapwing, redshank, avocet, ringed plover, and oystercatcher in the Klydesø reserve, eastern Denmark, from 1990 to 2001. We also include a proxy of winter climate, the index of the North Atlantic Oscillation (NAO), in our models in order to quantify the relative importance of the applied management and winter severity. Lapwing and avocet breeding numbers increased significantly concurrent with the application of cattle grazing, most likely due to an increased number of nesting sites and/or improved predator detection. Conversely, oystercatcher breeding numbers declined as the fraction of the reserve grazed by cattle increased, which may be attributed to changes in food availability on the grazed areas, but also due to increased predation risk. Ringed plover and redshanks in particular responded positively to the introduction of winter flooding, possibly due to increased availability of suitable foraging sites. Ringed plover may also experience increased nest site availability after winter flooding. Oystercatcher and ringed plover were both affected by winter severity, but with opposite trends, and oystercatcher breeding numbers increased after mild winters, while ringed plover decreased. Remaining species were not influenced by winter severity. The possible reason for this is discussed by comparing the lapwing breeding numbers in Klydesø reserve to Tipperne reserve in western Denmark. Though winter severity may seem of no importance for some of the species in the Klydesø reserve, it may still be important in areas where the management effort is constant.Die Versuche, die Populationsabnahme vieler Watvogelarten in Dänemark und anderen Teilen Europas in den letzten 20–30 Jahren umzukehren, resultierten in der Anwendung verschiedener Management-Methoden. In dieser Studie bewerten wir die Auswirkung von zwei Management-Methoden (Viehbeweidung und Winterüberflutung) auf die Anzahl der Brutpaare von Kiebitz, Rotschenkel, Säbelschnäbler, Sandregenpfeifer und Austernfischer im Klydesø Schutzgebiet, östliches Dänemark, von 1990 bis 2001. Wir nahmen ausserdem eine Stellvertretervariable für das Winterklima in unsere Modelle auf, den Index der Nordatlantischen Oszillation (NAO), um die relative Wichtigkeit des angewendeten Managements und der Winterhärte zu quantifizieren. Die Brutvogelzahlen von Kiebitz und Säbelschnäbler nahmen signifikant mit dem Einsatz der Viehbeweidung zu, am wahrscheinlichsten aufgrund einer erhöhten Anzahl von Brutplätzen und/oder aufgrund einer verbesserten Räuberwahrnehmung. Die Brutvogelzahl der Austernfischer nahm dazu gegenläufig mit der Zunahme des von Vieh beweideteten Anteils des Schutzgebietes ab, was auf die Veränderung der Nahrungsverfügbarkeit in den beweideten Flächen zurückzuführen sein mag, aber auch auf ein erhöhtes Prädationsrisiko. Besonders die Sandregenpfeifer und Rotschenkel reagierten positiv auf die Einführung der Winterüberflutung, möglicherweise aufgrund der erhöhten Verfügbarkeit von Nahrungshabitaten. Sandregenpfeifer könnten ebenfalls eine erhöhte Brutplatz-Verfügbarkeit nach der Winterüberflutung erfahren.Die Austernfischer und Sandregenpfeifer waren von der Winterhärte beeinflusst, jedoch mit gegenläufigen Trends. Die Brutvogelzahlen der Austernfischer nahmen nach milden Wintern zu, während die der Sandregenpfeifer abnahmen. Die bleibenden Arten wurden nicht von der Winterhärte beeinflusst. Der mögliche Grund dafür wird erörtert, indem wir die Brutvogelzahlen der Kiebitze zwischen dem Klydesø Schutzgebiet und dem Tipperne Schutzgebiet im westlichen Dänemark vergleichen. Obwohl die Winterhärte für einige der Arten im Klydesø Schutzgebiet keine Wichtigkeit zu haben schien, kann sie immer noch in Gebieten wichtig sein, in denen das Management gleichbleibend ist.     

Hyporheic community composition in a gravel-bed stream: influence of vertical hydrological exchange, sediment structure and physicochemistry

Summary 1. We studied the relative contributions of the magnitude and direction of vertical hydrological exchange, subsurface sediment composition and interstitial physicochemistry in determining the distribution of hyporheic invertebrates in the Kye Burn, a fourth order gravel‐bed stream in New Zealand. 2. In winter 2000 and summer 2001, we measured vertical hydrological gradient (VHG), dissolved oxygen, water temperature and water chemistry using mini‐piezometers, each installed in a different upwelling or downwelling zone. Next to every piezometer, a freeze core sample was taken to quantify the sediment, particulate organic matter and invertebrates. 3. Dissolved oxygen concentration at 25 cm was high on both occasions (>9 mg L^?1) but was higher in winter than summer. Interstitial water temperature was higher in down than upwellings and was substantially higher in summer than winter. Other features of the subsurface sediments and interstitial nitrate–nitrite concentrations were similar on both occasions and in up and downwellings. Interstitial ammonium and soluble reactive phosphorous concentrations were higher in winter than summer and ammonium was higher in up than downwelling areas. 4. The proportion of fine sediment (63 μm–1 mm), sediment heterogeneity and VHG accounted for the greatest proportion of variance in invertebrate distributions in both summer and winter. 5. The hyporheos was numerically dominated by early instar leptophlebiid mayfly nymphs and asellotan isopods. Water mites were a taxonomically diverse group with 13 genera. Taxonomic diversity (Shannon–Weaver), but not taxon richness, was higher in upwelling areas, reflecting lower numerical dominance by a few taxa in these locations. 6. Sediment composition (particularly the amount of fine sediments) and vertical hydrological exchange determined the composition and distribution of the hyporheos. Patchiness in these factors is important in planning sampling regimes or field manipulations in the hyporheic zone.