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91.
The examination of the type series of Ophiotaenia Gallardi (Johnston, 1911) (syn. Proteocephalus gallardi Johnston, 1911) revealed that it is a mixture of two species of different genera. Lectotype of Ophiotaenia gallardi is designated and the species is redescribed on the basis of it, conspecific paralectotypes and additional materials. The remaining part of the type series belongs to Vandiermenia gen. n. (Acanthotaeniinae), with V Beveridgei sp. n. as the type- and only species. The new genus differs from all other acanthotaeniine genera, i.e. Rostellotaenia Freze, 1963, Acanthotaenia von Linstow, 1903 and Kapsulotaenia Freze, 1963, by the presence of cortical uterine stem and paramuscular vitelline follicles, particular structure of the internal longitudinal musculature (absent laterally and more developed than in the three above-mentioned genera) and testes limited in two fields separated medially. Type series of Ophiotaenia mjobergi (Nybelin, 1917) (syn. Crepidobothrium mjobergi Nybelin, 1917), O. amphiboluri (Nybelin, 1917) (syn. Crepidobothrium amphiboluri Nybelin, 1917), O. striata (Johnston, 1914) (syn. Acanthotaenia striata Johnston, 1914) and O. longmani Johnston, 1916 are revised and compared with Ophiotaenia gallardi. Australotaenia hylae (Johnston, 1912) comb. n. is proposed for Ophiotaenia hylae Johnston, 1912. Australotaenia gen. n. differs from the remaining genera of the subfamily Acanthotaeniinae by (1) the Type 2 of the formation of the uterus (sensu de Chambrier et al. 2004) (all the other acanthotaeniines have the Type 1 of uterine development), (2) the cortical position of the uterine stem (all the other genera have medullary uterine stem) and (3) the morphology of the internal longitudinal musculature, which is composed of few well-developed bundles of fibres (in contrast to the other genera). The new genus also differs from ?by eggs not in clusters, the presence of two testicular fields (versus one in Vandiermenia) and the structure of the longitudinal internal musculature with only 8-10 bundles (versus formed by numerous bundles and with the presence of secondary muscles in Vandiermenia). Ophiotaenia sp. sensu de Chambrier (2004), a parasite of Litoria moorei, is described as Australotaenia grobeli sp. n., which can be distinguished from Australotaenia hylae by the smaller number of testes (46-76 versus 74-106), greater cirrus-sac length/width of proglottis ratio (27-33% versus 17-19%) and the smaller ovary width/proglottis width ratio (55-63% versus 68-71%). 相似文献
92.
Volume change of bread and bread crumb during cooling,chilling and freezing,and the impact of baking
Mohamed Fadhel Ben Aissa Jean-Yves Monteau Annick Perronnet Guillaume Roelens Alain Le Bail 《Journal of Cereal Science》2010
During baking, bread dough undergoes an expansion followed by a slight contraction at the end of baking. The contraction during baking has been evidenced by some authors. However, there is a limited amount of literature about the contraction of the crumb during the chilling phase and also during the freezing phase in the case of freezing. A study has been carried out to better understand the impact of the baking degree on the contraction of the crumb during chilling after baking and during freezing. The volume of the samples has been evaluated with a laser volumeter. Breads (70 g dough) were baked until reaching 75 °C, 85 °C, 95 °C, 98 °C and then 98 °C for 10 min. Results showed that a longer baking resulted in a lower contraction of the bread. The volume change was between 25% and 2.5% for baking at 75 °C—0 min dwell and 98 °C—10 min dwell, respectively. The contraction was compared to the contraction of degassed bread crumb samples, which was more important. SEM pictures showed that the degree of baking also corresponded to a very different structure of the crumb. For the longer baking, the starch granules were fully gelatinized and no ghosts of starch granules were visible. The magnitude of the contraction was thus associated with the degree of baking and with the degree of starch granule destructuration. 相似文献
93.
Amélie Collard Line Lapointe Jean-Pierre Ouellet Michel Crête Alain Lussier Claude Daigle Steeve D. Côté 《Forest Ecology and Management》2010
We examined the response of understory plants in mature maple-dominated forests of southern Québec, Canada, following about 30 years of high deer densities, using a deer exclosure experiment. An exclosure and a paired control of 625 m2 each were established on six sites in 1998. An exclosure and a paired control of 16 m2 were added at each of the same sites in 2003 but under a recent canopy gap to determine if light could enhance plant responses. We measured plant richness and abundance, and aboveground biomass of different plant groups for 8 years in the understory plots and for 3 years in the canopy gaps. Four herbaceous species were also monitored individually in the same plots. No significant differences between treatments were found in plots under forest cover, except for lateral obstruction at 0–50 cm height which was higher in the exclosures. Under canopy gaps, however, tree seedling and total plant abundance were higher in deer exclosures than in control plots. Trillium erectum recovered partially as individuals were taller, had larger leaves and more frequently produced a flower or a fruit in the absence of deer browsing under forest cover. To a lesser extent, Erythronium americanum and Maianthemum canadense also exhibited signs of recovery but were still at the single-leaf stage after 8 years of recovery. In general, the different plant groups exhibited little recovery following deer exclusion, possibly because of the low light levels that prevailed in the understory of undisturbed maple-dominated forests. The higher latitude of the present study could also contribute to the slow recovery rates of the different groups of plants compared to studies conducted in northeastern USA. Variability among sites and years had an effect on detection of statistically significant differences. Trends are however appearing over time, suggesting that many understory plants are recovering very slowly following deer exclusion. Our results emphasize the importance of studying large herbivore–forest interactions on different groups of plants, but also on specific species, and under different latitudes to be fully understood. 相似文献
94.
Many northern hardwood understory plants have medicinal properties but their cost of production under conventional cultivation
practices is fairly high. Therefore wild harvesting continues putting the natural populations at risk. Their cultivation in
a forest farming system seems a promising alternative. This study was aimed at assessing the impact of canopy opening and
soil fertility on growth and active component production of four medicinal plants: black cohosh (Actaea racemosa), wild ginger (Asarum canadense), blue cohosh (Caulophyllum thalictroides) and bloodroot (Sanguinaria canadensis). Rhizome sections were planted in two sugar maple forests. Mortality and total leaf area were monitored during 3 years,
while subplots were harvested at the end of the second year for biomass and active component analyses. Multiple regressions
indicated that all species responded more to acidity related elements (pH, Al, Al + H, Fe, Zn) than to soil fertility (Ca,
K, Mg, P, C/N, base saturation and cation exchange capacity). This suggests that adjusting the pH by liming could be appropriate.
Growth increased with irradiance, except for blue cohosh, indicating that forest openings could also be part of an appropriate
forest management plan for their cultivation. While active component concentrations of rhizomes and roots increased in conditions
that negatively affected growth, such as low pH, soil fertility or light availability, their total active component content
exhibited responses that were similar to those of the growth variables. Thus, it seems that soil and light conditions that
favour the growth of these medicinal plants also favour their total yield in active components. 相似文献
95.
Because of their highly polymorphic shell patterns, Cepaea land snails have been the subject of numerous studies in ecological genetics. Here, we investigated the spatial structure
of polychromatism in Cepaea hortensis in agricultural landscapes with zones from low to high hedgerow densities. Our main purpose was to search for a relationship
between landscape composition and spatial structuring of chromatism. Despite significant spatial heterogeneity in the three
landscapes sampled, only the high hedgerow density landscape showed a significant spatial structuring of shell polymorphism.
In order to understand this result, an investigation of daily movement patterns in relation to habitat form was carried out
on a mark-release experiment under semi-artificial conditions. This experiment revealed a strong influence of a linear corridor
on snail dispersal. In the field, spatial heterogeneity of shell polymorphism, related to the effects of genetic drift, was
shaped by restricted dispersal in narrow corridors. In the more enclosed one, i.e. where hedgerow density was the highest,
the significant spatial structure we detected involved a balance between local genetic drift and environmentally mediated
gene flow. This isolation-by-distance pattern resulted from direct gene exchange through fields between neighbouring populations.
When applying landscape distances based on hedgerow length, no significant spatial correlation with polychromatism was found.
In the more fragmented sites, random genetic drift seemed to be the prevailing force and, at the scale of the whole sampled
area, selective pressures potentially interfere with these genetic drift-dispersal events. 相似文献
96.
We investigated the indirect effect of an insecticide spray against the European Corn Borer (Ostrinia nubilalis Hübner; Lepidoptera: Crambidae) on mycotoxin contaminations of grain maize at the harvest stage. Between 2004 and 2009, 45 paired plots comparing insecticide treatment with untreated control were studied in Alsace administrative region, in the northeast of France. An average reduction of 78% in O. nubilalis larval densities was observed in insecticide-treated plots compared with control plots. Mean levels of deoxynivalenol mycotoxin in harvested grain were significantly reduced from 849 ppb in the control samples to 152 ppb in the insecticide-treated samples. A statistical modelling approach involving Generalized Linear Models (GLMs) was employed to identify and rank the associated variables for damage and pest density on different plant parts, on deoxynivalenol levels in harvested grain at harvest. The modelling revealed that the occurrence and the density of O. nubilalis larvae in maize stalks and in ears are the best indicators for deoxynivalenol contamination. The identification of these deoxynivalenol contamination risk factors, along with other factors such as genetic background, harvest date and crop rotation allows improvement of the risk assessment and risk forecasting in maize crops in order to manage crop safety and maintain maize deoxynivalenol mycotoxin levels below the European Regulation (EC) No. 1126/2007 threshold. 相似文献
97.
Muhammad Nadeem Alain Mollier Christian Morel Alain Vives Loïc Prud'homme Sylvain Pellerin 《植物养料与土壤学杂志》2012,175(6):805-809
Phosphorus (P) is the least mobile nutrient in the soil as compared to other macronutrients and therefore frequently limits crop growth. During germination and early growth, seed‐phytate hydrolysis and seed‐P remobilization is the major P source for developing seedlings. The objective of this paper was to investigate whether seed‐P hydrolysis and remobilization of nonphytate P are sufficient for seedling P nutrition during early growth stages of maize. A large part of initial maize endogenous seed P reserves are mainly in the form of phytate. Till 70 cumulated degree days after sowing, nearly all the phytate (98%) was hydrolyzed and caused an increase in nonphytate P in seeds. Phytate hydrolysis and remobilization of nonphytate P was the main source of P supply for the newly growing seedlings and was not a limiting step for seedling P nutrition during the first four weeks of early growth. 相似文献
98.
Florence Clostre Thierry Woignier Luc Rangon Paula Fernandes Alain Soler Magalie Lesueur-Jannoyer 《Journal of Soils and Sediments》2014,14(1):23-33
Purpose
The use of chlordecone (CLD) has caused pollution of soils, which are now a source of contamination for crops and ecosystems. Because of its long-term impacts on human health, exposure to CLD is a public health concern and contamination of crops by CLD must be limited. To this end, we conducted field trials on chlordecone sequestration in soil with added compost.Materials and methods
The impact of added compost on chlordecone sequestration was measured in nitisols. After characterization of the soil, the transfer of chlordecone from soil to water was assessed in a leaching experiment and from soil to two crop plants in a nitisol plot. Finally, to understand the underlying processes, changes in CLD content were measured in soil fractions and soil porous properties were assessed after the addition of compost.Results and discussion
A rapid seven-fold decrease in water extractable CLD was observed in amended soils. Five percent amendment led to a significant reduction in the contamination of crops by CLD; edible radish tubers were 50% more contaminated without added compost and cucumber fruits were 60% more contaminated. After the addition of compost, CLD content increased in the fraction of pre-humified or partially mineralized organic debris. Finally, in contrast to andosols, adding compost to nitisols did not affect the soil microstructure.Conclusions
Increasing chlordecone sequestration by adding compost could be an alternative solution until soil decontamination techniques become available. This could be a provisional way to control further release of CLD from contaminated soils towards other environmental compartments. 相似文献99.
van Beurden SJ Leroy B Wattiez R Haenen OL Boeren S Vervoort JJ Peeters BP Rottier PJ Engelsma MY Vanderplasschen AF 《Veterinary research》2011,42(1):105
ABSTRACT: Many of the known fish herpesviruses have important aquaculture species as their natural host, and may cause serious disease and mortality. Anguillid herpesvirus 1 (AngHV-1) causes a hemorrhagic disease in European eel, Anguilla anguilla. Despite their importance, fundamental molecular knowledge on fish herpesviruses is still limited. In this study we describe the identification and localization of the structural proteins of AngHV-1. Purified virions were fractionated into a capsid-tegument and an envelope fraction, and premature capsids were isolated from infected cells. Proteins were extracted by different methods and identified by mass spectrometry. A total of 40 structural proteins were identified, of which 7 could be assigned to the capsid, 11 to the envelope, and 22 to the tegument. The identification and localization of these proteins allowed functional predictions. Our findings include the identification of the putative capsid triplex protein 1, the predominant tegument protein, and the major antigenic envelope proteins. Eighteen of the 40 AngHV-1 structural proteins had sequence homologues in related Cyprinid herpesvirus 3 (CyHV-3). Conservation of fish herpesvirus structural genes seemed to be high for the capsid proteins, limited for the tegument proteins, and low for the envelope proteins. The identification and localization of the structural proteins of AngHV-1 in this study adds to the fundamental knowledge of members of the Alloherpesviridae family, especially of the Cyprinivirus genus. 相似文献
100.
Chorfi Y Girard V Fournier A Couture Y 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(10):1089-1094
This study measured the effect on glutathione peroxidase (GSH-Px) and selenium (Se) in whole blood and plasma associated with subcutaneous Se injections in beef heifers fed organic or inorganic Se. Heifers (n = 120) were randomly divided into 2 groups, 1 of which received subcutaneous Se injections. Both groups were given the same total mixed ration with 3 mg of organic or inorganic Se daily. Until week 2, heifers that had received Se injections showed higher concentrations of plasma Se and GSH-Px and whole blood Se (P < 0.001) than those having had no injections. Concentrations of plasma Se and GSH-Px were higher in the group receiving organic Se than the group receiving inorganic Se. Whole blood GSH-Px concentrations increased significantly (P < 0.001) throughout a 12-week period but were not affected by Se source. Combination of Se injections and supplementation could help maintain normal Se and GSH-Px blood status in beef heifers during the first few weeks in the feedlot. 相似文献