bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of successive cambia, cambial activity, and their relationship to physiological traits inIpomoea arborescens(Convolvulaceae) seedlings
Authors: Terrazas Teresa , Aguilar‐Rodríguez Silvia , Ojanguren Clara Tinoco 
Published: April 2011

•Premise of the study: The seedling stage is one of the most critical phases in the life history of plants; during this stage, plants must develop efficient conductive and storage systems before the end of the favorable season. Little is known about the origin of successive cambia in seedlings of tree species ofIpomoeaor about how many cambia are produced in one growth season. We studied the anatomy ofIpomoea arborescensseedlings to define when cambium is differentiated, to determine how many cambia differentiate in one year of growth, and to relate the development of successive cambia to physiological aspects of growth.•Methods: Seedlings from 5 to 425 d of age were harvested, and their morphology as well as CO2and water exchange, were evaluated at 5 and 60 d after germination. Six stages of development were established to study origin of cambia.•Key results: Cambium was differentiated 5 d after germination, at a time when seedlings had photosynthetic cotyledons with high specific area, assimilation rate, and stomatal conductance. Differentiation of the first successive cambium occurred in parenchyma cells below the endodermis or starch sheath. Development of reverse cambium and intraxylary phloem cambium demonstrated that ontogenetic shifts may occur in different stem regions. In the 10‐mo‐old plants, all cambia reactivated, and earlywood wide vessels were differentiated.•Conclusions: The origin of successive cambia, the occurrence of more than one type of cambium, and parenchyma proliferation are features shared byI. arborescenswith its climbing ancestors as a strategy for survival in the harsh environment of tropical deciduous forests.
Isolation of SSR markers for two African tropical tree species, Erythrophleum suaveolens and E. ivorense (Caesalpinioideae)
Authors: Duminil Jérôme , Koffi Guillaume K. , Debout Gabriel , Sebastiani Federico , Vendramin Giovanni G. , Heuertz Myriam , González‐Martínez Santiago C. , Hardy Olivier J. 
Published: April 2011

• Premise of the study: To characterize the level of genetic diversity and gene flow, as well as to identify unambiguously two African tropical tree species, Erythrophleum ivorense and E. suaveolens, we have developed a set of nuclear SSR (Simple Sequence Repeats) markers.• Methods and Results: Nine SSRs that display polymorphism in both species were identified. The nine newly developed SSR markers can be amplified in only two multiplexed reactions. Levels of polymorphism were assessed in two populations per species, yielding two to fifteen alleles per locus in E. ivorense and three to sixteen alleles per locus in E. suaveolens.• Conclusions: The SSR markers developed here are promising to study the spatial distribution of genetic diversity and the genetic delimitation of two Erythrophleum species from central Africa.
Using the 454 pyrosequencing‐based technique in the development of nuclear microsatellite loci in the alpine plant Arabis alpina (Brassicaceae)
Authors: Buehler Dominique , Graf René , Holderegger Rolf , Gugerli Felix 
Published: April 2011

• Premise of the study: Polymorphic microsatellite markers were developed for the inbred alpine perennial plant Arabis alpina to infer life‐history parameters and measure patterns of contemporary gene flow within populations.• Methods and Results: Using the 454 pyrosequencing technique, 19 microsatellite primer sets were developed for A. alpina. The primer sets were tested on 60 individuals sampled from three sub‐populations in the Swiss Alps. The primers amplified di‐ and trinucleotide repeats with two to five alleles per locus.• Conclusions: Previous attempts to isolate microsatellite loci in A. alpina using enrichment libraries and cross‐amplification were difficult and produced an insufficient number of polymorphic microsatellite loci. In contrast, next‐generation sequencing technology was successful in identifying microsatellite repeats in A. alpina. These newly developed microsatellite primers will be useful to further develop A. alpina into a model species for eco‐genomic studies.
La citoyenneté à l'épreuve des rites : l'exemple des réunions de foyer dans un dispositif d'éducation spécialisée
Authors: Ossipow Laurence 
Published: April 2011

Résumé Choisissant de définir a posteriori les moments qui, selon certaines dimensions, peuvent être compris comme des rites tandis que d’autres ressortent de la chronique ordinaire d’une institution, nous avons enquêté sur la vie quotidienne de trois foyers éducatifs genevois accueillant des adolescent-e-s de 14 à 18 ans selon différents types de placements. Parmi d’autres rites (étapes de placement, lever, coucher, repas, anniversaire, fêtes calendaires, camp, sorties d’institutions...), nous avons en particulier analysé les réunions de foyers parce qu’elles nous semblaient être riches en information sur la façon dont est exercé l’apprentissage formel et informel de la citoyenneté, une des missions principales (avec celle de l’autonomisation) que les équipes éducatives mettent en œuvre. Ces réunions hebdomadaires, qui rassemblent tous-toutes les jeunes placé-e-s ainsi qu’une partie des éducatrices et des éducateurs, régulent la vie collective, rappellent les règles de l’institution, gèrent des conflits menaçant le vivre-ensemble, ravivent un certain sentiment d’appartenance au foyer et font expérimenter certaines formes de citoyenneté et de civilité. Elles permettent aussi d’entériner certains changements individuels ou collectifs. Ce sont donc des moments de régulation, mais aussi, pour emprunter une expression d’Albert Piette, des « espaces de réflexion » (au double sens du terme) du groupe et sur le groupe.
THE SYSTEMATICS AND TAXONOMY OF FINAL-INSTAR LARVAE OF THE FAMILY APHIDIIDAE (HYMENOPTERA)
Authors: Finlayson Thelma 
Published: April 2011

AbstractCharacteristics of cephalic structures and spiracles of final-instar larvae of 65 species in 18 genera of the family Aphidiidae (Hymenoptera) are described and illustrated and keys are given for identification of genera and species. An additional seven species that were described and illustrated in an earlier paper (Mackauer and Finlayson 1967) are redescribed and included in the keys for a total of 72 species.On the basis of characteristics of final-instar larvae, taxonomic groupings of the family Aphidiidae mainly conform to those based on characteristics of adults, with the following exceptions.Within the tribe Aphidiini the genus Calaphidius appears to belong in a new subtribe because of the unusual form of the pleurostoma, and the presence of numerous small sensoria in the maxillary and labial palpi, and of an atrium in the prothoracic spiracle which is absent in all other species of this tribe.It is suggested that the tribe Trioxini (Aphidiinae) should be a separate subfamily, the Trioxinae, because of the presence of a hypostomal spur which was not found in any of the other aphidiids examined. Within this suggested new subfamily the genus Lipolexis appears to be the most primitive form examined because, in addition to a hypostomal spur, it has a complete epistoma which is lacking in all other aphidiids examined; it is suggested that this genus be placed in a separate tribe, the Lipolexini. The trioxines appear to be the most primitive of the Aphidiidae and form a bridge between the Braconidae and the Aphidiidae.The Aphidiini (Aphidiinae) appear to be at the peak of the evolutionary scale of the Aphidiidae because of the loss or reduction of the pleurostomal–hypostomal sclerite, making the identities of the pleurostoma and hypostoma less distinguishable.
2.0 MASS-PRODUCTION OF TRICHOGRAMMA MINUTUM RILEY ON FACTITIOUS HOST EGGS
Authors: Laing J.E. , Eden G.M. 
Published: April 2011

AbstractA system was developed to produce large numbers (30 × 106 per week) of Trichogramma minutum Riley on eggs of the Angoumois grain moth, Sitotroga cerealella (Olivier). The parasitized host eggs were packaged and shipped in bulk for release against the spruce budworm, Choristoneura fumiferana (Clemens), and several other lepidopterous pests. Initial attempts to use the Mediterranean flour moth, Ephestia kuehniella (Zeller), as a host failed due to such factors as infestation by mites and parasitoids, low fecundity, long generation time, and the necessity for large labour inputs during moth collection. Eggs of S. cerealella, used to rear the host, remained viable when stored for up to 1 month at 9 °C, but eggs stored at 2 °C remained acceptable for parasitism for only 15 days. Rearing the host at high humidity (> 70% RH) gave better percentage emergence and infestation of grain than rearing at low humidity (< 30% RH). Developmental rates of T. minutum were determined over a range of temperatures and the developmental threshold and heat unit accumulations necessary for complete development were calculated. Using these values, Trichogramma were programmed, during the latter stages of production, to emerge within 24 h of exposure to light at room temperature. The programming facilitated shipment and handling of the parasitoids prior to their release.
3.2 GROUND SYSTEMS FOR RELEASING TRICHOGRAMMA MINUTUM RILEY IN PLANTATION FORESTS
Authors: Smith S.M. , Wallace D.R. 
Published: April 2011

AbstractTwo systems for releasing the egg parasitoid, Trichogramma minutum Riley, from ground level in forest stands are described: (1) a gridded point-source release using parasitized host eggs attached to cards, and (2) a hand-held leafblower distributing parasitized eggs in bulk. Neither technique affected the emergence of the parasitoids released. Parasitoids emerging from eggs released in bulk had a similar sex ratio, longevity, and fecundity to those not released. Both methods of ground release achieved uniform parasitoid distribution and resulted in levels of parasitism similar to those achieved with aerial releases. Parasitism was greater in the mid- to upper canopy of trees than in the lower canopy. The difficulties associated with each technique and its comparative usefulness in experimental and operational programs are discussed.
NATURAL HISTORY, CLASSIFICATION, RECONSTRUCTED PHYLOGENY, AND GEOGRAPHIC HISTORY OF PYTHO LATREILLE (COLEOPTERA: HETEROMERA: PYTHIDAE)
Authors: Pollock Darren A. 
Published: April 2011

AbstractThe classification of the nine world species of Pytho Latreille is reviewed by study of adult, larval, and pupal stages. Keys are provided for separation of species in these three life stages. Taxonomic changes (senior synonym in brackets) include synonymy of P. fallax Seidlitz 1916 [= P. niger Kirby 1837]; P. americanus Kirby 1837 [= P. planus (Olivier 1795)]; P. deplanatus Mannerheim 1843 is transferred from a junior subjective synonym of P. depressus (Linnaeus 1767) to a junior subjective synonym of P. planus (Olivier 1795). Lectotype designations are provided for the following: P. seidlitzi Blair 1925; P. nivalis Lewis 1888; P. niger Kirby 1837; P. fallax Seidlitz 1916; P. abieticola J. Sahlberg 1875; and P. americanus Kirby 1837. Eight larval stage, and 12 adult stage characters were selected for cladistic analysis. Lacking out-group material, pupal characters were not analysed. Character states were polarized using a generalized out-group composed of the three other genera of Pythinae (all monobasic). Phylogenetic analysis based on these 18 characters suggests four monophyletic species-groups: P. seidlitzi group (P. seidlitzi Blair — North America); P. kolwensis group (P. strictus LeConte – North America, P. kolwensis C. Sahlberg —Fennoscandia and the U.S.S.R., P. nivalis Lewis — Japan); P. niger group (P. niger Kirby — North America, P. abieticola J. Sahlberg — Europe, P. jezoensis Kôno — Japan); P. depressus group [P. planus (Olivier, 1795) — North America, P. depressus (Linnaeus, 1767) — Europe and the U.S.S.R.]. Larval stage synapomorphies are relatively more important in defining the species-groups than are those of the adult stage. The ancestor of Pythidae may have been associated with Coniferae as early as the Jurassic. The common ancestor of Northern Hemisphere Pythinae became isolated upon Laurasia once separation from Gondwanaland occurred near the end of the Jurassic. Two of the species-groups have similar disjunctions in North America, Europe, and Japan. The relatively eastern distributions of the North American member of each suggests that the ancestor of each species-group was Euramerican, and underwent vicariance with the opening of the North Atlantic in the Middle Cretaceous. The present distribution of both species-groups is thought to have been caused by the same vicariant event. The ancestor of the P. depressus group, which is presently circumboreal, was probably widespread and could have been Asiamerican in distribution. In the middle to late Tertiary, evidence suggests that Beringia was covered with coniferous forest, and the ancestor of the P. depressus group probably extended across this land bridge. Final separation between any North American and European/Asian species occurred in the Late Miocene or Pliocene, when a cooling climate made possible the evolution of treeless tundra in the north.
DESCRIPTION OF PARABROCHYMENA, NEW GENUS, AND REDEFINITION AND REVIEW OF BROCHYMENA AMYOT AND AUDINET-SERVILLE (HEMIPTERA: PENTATOMIDAE), WITH CONSIDERATIONS ON NATURAL HISTORY, CHOROLOGICAL AFFINITIES, AND EVOLUTIONARY RELATIONSHIPS
Authors: Larivière Marie-Claude 
Published: April 2011

AbstractFrom the endemic New World halyine genus Brochymena, two genera are recognized. New morphological characters at the generic level are described. Parabrochymena, new genus, with Pentatoma arborea Say as type species, is erected to contain 10 taxa formerly included in Brochymena. New combinations are Parabrochymena aculeata (Distant), P. apiculata (Van Duzee), P. arborea (Say), P. barberi barberi (Ruckes), P. barberi diluta (Blatchley), P. cuspidata (Distant), P. enigmatica (Ruckes), P. florida (Ruckes), P. haedula (Stål), and P. poeyi (Guérin-Méneville). Brochymena is redefined with 20 taxa: B. affinis Van Duzee, B. cariosa Stål, B. carolinensis (Westwood), B. chelonoides Ruckes, B. dilata Ruckes, B. exardentia Ruckes, B. hoppingi Van Duzee, B. humeralis Ruckes, B. laevigata Ruckes, B. lineata Ruckes, B. marginella Stål, B. myops Stål, B. parva Ruckes, B. punctata punctata Van Duzee, B. punctata pallida Blatchley, B. pilatei Van Duzee, B. quadripustulata (Fabricius), B. splendida Ruckes, B. sulcata Van Duzee, and B. tenebrosa Walker. Four synonymies are established: B. marginella Stål = B. carolinensis (Westwood); B. pilatei Van Duzee = B. sulcata Van Duzee; B. laevigata Ruckes = B. myops Stål; B. exardentia Ruckes = B. lineata Ruckes. Lectotypes are designated for B. affinis Van Duzee, B. cariosa Stål, B. myops Stål, B. punctata pallida Blatchley, and B. p. punctata Van Duzee. Species groups of Brochymena are characterized, and a key to all taxa is presented for the first time. As appropriate, for each species of Brochymena, the following are provided: citation of original description, synonymies, type material, diagnosis, description, geographical distribution, taxonomic comments, natural history, and illustrations of important structural characters. Chorological affinities are presented and systematic relationships are hypothesized.
The effect of storage of cereal grain and enzyme supplementation on measurements of AME and broiler chick performance
Authors: Scott T. A. , Pierce A. B. 
Published: April 2011

There is a concern that feeding newly harvested cereal grain results in poor performance in poultry. A broiler chick apparent metabolizable energy (AME) bioassay was used to measure changes in feeding value of wheat (n = 14), hulless (n = 10) and hulled (n = 14) barley with or without a commercial enzyme appropriate for wheat- or barley-based diets. In the broiler chick bioassay, four pens of six male broiler chicks were fed ad lib, from 4 to 17 d, diets containing 80% of a test cereal grain and a high-protein basal mixture containing 1% “celite” as an acid-insoluble ash marker. Each of the cereal-grain-based diets, with or without enzyme, was tested within 3 mo of harvest and again 6 mo later. With cereal grain storage there were consistent (P < 0.05) increases in feed intake (FI) between 4 and 17 d and body weight (BW) at 17 d of age with wheat-based diets fed wit h (12.5 and 16.9%, respectively, for FI and BW) or without (16.1 and 22.7%) enzyme. In hulless barley diets without enzyme, there was a significant improvement in BW (7.5%) with storage, while storage had a significant effect on FI and BW (2.9 and 6.3%, respectively) when fed with enzyme. For all other barley diets there was a positive effect of storage on FI and BW, but it was not significant. Feed conversion ratios decreased marginally (P > 0.05) with storage of cereal grain. AME of diets was improved within each period by enzyme supplementation. However, there were measurable decreases (P < 0.05) in AME with storage of cereal grains for the three cereal grains with enzyme supplementation (ranging from –3.2 to –8.2%). The r2 of the above measurements for the different sources of cereal grain between storage periods ranged from 0.65 to 0.94, indicating that the relative ranking of the cereal grains, with respect to feeding value, remained similar during storage. Increases in FI with storage were not significantly related to the attempts of the broiler chicks, to maintain metabolizable energy (ME) intake. Therefore, this increases our concerns that “factors” in newly harvested cereal grains may exist and that they may limit voluntary feed intake and/or growth. Key words: Cereal grain storage, AME, broiler performance, wheat, barley
Effect of artificially eroded Dark Brown Chernozemic soil and subsequent amendments on the milling and baking quality of wheat under dryland conditions
Authors: Dormaar J. F. , Lukow O. M. , Lindwall C. W. , Kozub G. C. 
Published: April 2011

A field was artificially eroded by levelling in 1957. It was continuously cropped to barley for 7 yr. Subsequently, the field was cropped to a wheat-fallow rotation up to but not including 1986. Two major restoring productivity experiments were conducted over that time period. After 30 yr and 19 crops, a third experiment was established to determine the effect of artificial soil erosion and four restorative amendments on 13 wheat quality characteristics. Year, erosion level, and amendment all had significant effects on many wheat quality parameters. Erosion decreased overall quality, mainly by decreasing protein content which in turn affected other quality characteristics. Applications of manure, fertilizer, and straw + fertilizer increased protein content and related characteristics substantially compared to the check. Since high-quality bread wheat is central to its worldwide demand, prevention of soil erosion is essential. Conversely, eroded soil can be ameliorated with amendments but at a cost of the amendment and its application. Keywords: Soil erosion, topsoil loss, wheat quality, soil moisture, fertility amendment
Seasonal denitrification rates under corn (Zea mays L.) in two Quebec soils
Authors: Liang B. C. , MacKenzie A. F. 
Published: April 2011

Nitrogen losses in soil through denitrification are important due to reduced agronomic effectiveness and environmental concerns with nitrous oxide emissions. Knowledge of denitrification may allow for management procedures to reduce these losses. Field experiments were conducted in 1991 and 1992 to investigate N fertilizer effects on denitrification under corn (Zea mays L.) on two soils of contrasting texture in southwestern Quebec. Soil core incubation with C2H2 was used to assess denitrification rates. Total calculated denitrification rate from April to November in 1991 and 1992 varied from 4 to 41 kg N ha−1 on a Chicot sandy clay loam and from 29 to 53 kg N ha−1 on a Ste. Rosalie clay. Denitrification rates increased linearly with increasing fertilizer N rates only in the Ste. Rosalie clay in 1991. Denitrification in the Ste. Rosalie soil was positively related to temperature and NO3− levels in April and May, moisture content from August to November, and temperature in October and November. Denitrification in the Chicot soil was positively related to soil moisture content and NO3− levels in April and May, and soil moisture content in June. Reducing soil NO3− concentrations in April and May could decrease denitrification rate in both Chicot and Ste. Rosalie soils. Key words: Denitrification, fertilizer N, temperature, moisture content
Review and performance of four models to assess the fate of radionuclides and heavy metals in surface soil
Authors: Sheppard M. I. , Elrick D. E. , Peterson S. R. 
Published: April 2011

The nuclear industry uses computer models to calculate and assess the impact of its present and future releases to the environment, both from operating reactors and from existing licensed and planned waste management facilities. We review four soil models varying in complexity that could be useful for environmental impact assessment. The goal of this comparison is to direct the combined use of these models in order to preserve simplicity, yet increase the rigor of Canadian environmental assessment calculations involving soil transport pathways. The four models chosen are: the Soil Chemical Exchange and Migration of Radionuclides (SCEMR1) model; the Baes and Sharp/Preclosure PREAC soil model, both used in Canada's nuclear fuel waste management program; the Convection-Dispersion Equation (CDE) model, commonly used in contaminant transport applications; and the Canadian Standards Association (CSA) derived release limit model used for normal operations at nuclear facilities. We discuss how each model operates, its timestep and depth increment options and the limitations of each of the models. Major model assumptions are discussed and the performance of these models is compared quantitatively for a scenario involving surface deposition or irrigation. A sensitivity analysis of the CDE model illustrates the influence of the important model parameters: the amount of infiltrating water, V; the hydrodynamic dispersion coefficient, D; and the soil retention or partition coefficient, Kd. The important parameters in the other models are also identified. This work shows we need tested, robust, mechanistic unsaturated soil models with easily understood and measurable inputs, including data for the sensitive or important model parameters for Canada's priority contaminants. Soil scientists need to assist industry and its regulators by recommending a selection of models and supporting them with the provision of validation data to ensure high-quality environmental risk assessments are carried out in Canada. Key words: Soil transport models, environmental impact assessments, model structure, complexity and performance, radionuclides 137Cs, 90Sr, 129I