Academic literature on the topic 'Aleurode des serres'

The petrographic, lithogeochemical and U-Pb (LA-ICP-MS) geochronological studies were carried out to investigate the terrigenous rocks sampled from the lower part of the Ipsit suite of the Karagass series (Sayan segment of the Sayan-Baikal-Patom belt). These rocks include sandstones, aleurite sandstones and aleurolites, and their mineral compositions are close to that of arkose. Most of the studied rock samples show petrographic features typical of the epigenetic changes at the stage of catagenesis: regeneration of quartz clastic grains, pelitization of potassium-feldspar clastic grains, occurrence of clay-hydromica aggregate, sericitization of plagioclase, chloritization of biotite, and silicification of dolomite pieces, and occurrence of authigenous tourmaline. The above was confirmed by the analysis of the concentrations of petrogenic elements in the studied rocks from the lower part of the Ipsit suite. The analysis results show that the concentrations of K2O are elevated, while the concentrations of Na2O are relatively very low, which may be due to the redistribution of these elements during epigenetic transformations. According to the classification by genetic types on the basis of the system of petrochemical modules, the rocks of the lower part of the Ipsa suite are of the petrogenic nature. The acidic igneous rocks are dominant in the source area, as evidenced by the presence of granitoid and quartzite fragments in the clastogenic component, as well as the set of accessory minerals typical of the igneous rocks of the acidic composition, and the distribution pattern of rare and trace elements. According to the U-Pb (LA-ICP-MS) dating of detrital zircons from the aleurite sandstone sampled from the lower part of the Ipsit suite, the zircons are exclusively of the Archean-Early Proterozoic ages. Such ages correlate with the age of the granitoids of the Sayan complex and the felsic volcanites from the Maltsev layer of the Elash series (Biryusa block). Furthermore, the detrital-zircon age spectra of the aleurite sandstone of the lower part of the Ipsit suite are identical to the detrital-zircon age spectra of the terrigenous rocks from the underlying strata of the Shangulezh and Tagul suites of the Karagass series. This study suggests that sedimentation of the Ipsit suite of the Karagass series took place due to the influx of detrital material from the southern part of the Siberian craton into the sedimentation basin, and the acidic igneous rocks of the Biryusa block were one of the main sources of detrital material.

The present work was undertaken to study the gastrointestinal effects of wheat and oat dietary fibre (DF) using 40–50 kg pigs cannulated in the terminal ileum. The variables studied were: chemical characteristics of the DF, ileal and faecal digestibility of nutrients and bulking properties of polysaccharides and other major constituents. The wheat products studied included refined wheat flour and wheat fractions rich in the following botanical components: aleurone, pericarp/testa and bran. The oat products used were rolled oats and oat bran. The products varied considerably in DF content (g/kg dry matter) and composition; non-starch polysaccharides (NSP) and Klason lignin content ranged from 34 and 1 g/kg respectively in wheat flour, to 465 and 92 g/kg in pericarp/testa. The main NSPs in the wheat were arabinoxylans (AX) (64–69%) and cellulose (15–31%) and in oats mixed linked β(1 → 3; 1 → 4)-D-glucans (β-glucans; 46–63%) and AX (28–32%). The lowest content of soluble NSP was found in the lignified wheat fractions (bran and pericarp/testa) and the highest in oat bran. Eight diets were produced using the wheat and oat products and studied in two series of experiments using wheat flour as the DF-depleted control. The diets in Expt 1 were based on wheat flour and three iso-DF enriched diets prepared by adding DF from the fractions rich in wheat aleurone, pericarp/testa or bran. In Expt 2, oat bran was added to wheat flour to achieve the same DF intake level as in Expt 1. This series also included diets based on rolled oats and rolled oats plus oat bran. Starch was almost completely digested in the small intestine (0.97–1.00). However, there was a tendency to a slightly lower digestibility of oat starch compared with wheat starch. The recovery of wheat NSP in ileal digesta was 82–104 % compared with 64–66% for oats. The low recovery of NSP in oat diets was primarily due to the low recovery of β-glucans (25–36%). In the large intestine NSP and starch residues were extensively degraded. For the DF-depleted control diets or diets based on oats, 8–17% NSP survived breakdown while in the diets enriched with aleurone, pericarp/testa or bran fractions, NSP recovery was 33, 50 and 38 % respectively. Fermentative breakdown of carbohydrates in the large intestine was estimated to contribute between 10 and 24 % of the energy for maintenance. Energy derived from the inflow of organic acids from the ileum contributed an additional 1–4% of maintenance energy. In wheat endosperm, AX were broken down to a greater extent than cellulose, while the breakdown of AX in pericarp/testa was similar to that of cellulose. This difference in NSP breakdown can be explained by structural differences in the two types of cell walls. The breakdown of oat AX was lower than that of wheat flour. Wheat DF increased faecal bulk primarily by virtue of its physical presence and its water-holding capacity, while the oat DF stimulated faecal output through an increase in microbial biomass (Bach Knudsenet al.1991). The result was a higher excretion of protein and fat. The higher fat excretion with the oat diets was probably due to a higher bile acid excretion caused by the more extensive fermentation of carbohydrates and the lower lumen pH.

Electrophoretic analysis of sorghum (Sorghum bicolor (L.) Moench) seed prolamines in the presence of sodium dodecyl sulfate reveals major proteins of 27 and 25 kDa and two other proteins of 18 and 12 kDa. Antibodies were raised against this prolamine fraction and used to examine the subcellular distribution of the proteins in developing sorghum seeds. Protein bodies in the starchy endosperm and subaleurone cells usually are round in cross section and contain darkly staining materials arranged in concentric rings. Protein bodies in the first two layers beneath the aleurone layer are irregular in shape and contain discrete pockets of light and dark staining inclusions. Prolamines were detected in both types of protein bodies by immunolabeling. Other oganelles, including Golgi complexes, mitochondria, and amyloplasts, were not labeled. The protein bodies, which have ribosomes attached to their surfaces, are directly connected to the rough endoplasmic reticulum. In some instances, this endoplasmic reticulum was specifically labeled with protein A – gold particles. Based on these observations, we suggest that the rough endoplasmic reticulum serves as the site of both synthesis and accumulation of sorghum prolamines.

The aim of the study is to develop methods for prediction of the vertical distribution of characteristics of sand and aleurite sediment suspended by tidal flow for the averaging time either divisible by tidal period (the first order model) or much less than it is (the second order one). The bottom is assumed to be erodible with possible formation of ripples. Part I: The theoretical and laboratory study of steady flow with suspension is used to develop the solution. The concentration field of heterogeneous sediment is considered as a sum of those of homogeneous groups of particles (fractions) moving under the same regulations. In the first order model, the hydrodynamical characteristics of the tidal flow are represented by their constant effective values. In the second order model the tidal flow is represented by the series of consecutive steady states (steps).

North Absheron folded zone is closely located to Turan plate and separated from Turkmenbashy-Predcaucasus deep fault. However, North Absheron folded zone has a complicated geological structure; local structures here are of platform character, unlike in the west and north-west part of the region, where formation of the sediments of Mio-Pliocene and Cretaceous-Paleogene stages became significantly complicated due to the high hypsometric state of the surface of Mesozoic folding and the increase of regional and interstratified washaways and bracits as well. The paper specifies the stratigraphy of Mio-Pliocene stages within the west part of the region in the structures of Absheron group, Agburun-deniz and Iki-gardash, marking the absence of the sediments of lower part of Productive Series. Due to the new findings of mactra fauna, the washaway of significant part of the Upper Miocene (Pontian, Miotice and Upper Sarmatian) has been justified. According to the fauna remains and the mineralogical-petrographic composition of Absheron group rocks, only Sarmatian and Chokrak sediments from the Miocene stage outcrop in the sections of deep wells, which unconformable occur in the aleurite-clay series of Maikop stage. The Lower Pliocene in West Absheron structure appear only in a short volume – Balakhany suite occurring in the monomict quartz sandstones of fluvial-distributary origin. Grey Miocene series appear with the alternation of units of polymict sandstones and grey hydromicaceous-kaolinite clay with interlayers of cement stones. Maikop series appear in short extent and occur in polimict aleurites and brown-grey clays including calcite-siderite concretion.

The present work was undertaken to study the microbial activity in various segments of the gastrointestinal (GI) tract of pigs as influenced by the source and level of wheat and oat dietary fibre (DF). Eight experimental diets were prepared from wheat and oat fractions and studied in a series of two experiments using wheat flour as the DF-depleted control. The diets in Expt 1 were based on wheat flour and three iso-DF enriched diets comprising fractions rich in wheat aleurone, pericarp/testa or bran. In Expt 2, oat bran was added to wheat flour to achieve the same DF intake level as in Expt 1. This series included further diets based on rolled oats and rolled oats plus oat bran. The eight diets were given to thirty-two ileal-cannulated pigs, with sixteen pigs in each experiment. After a total period of 34 d (Expt 1) and 42 d (Expt 2), the pigs were slaughtered 4 h post-feeding and samples taken for adenine nucleotides (adenosine 5'-triphosphate (ATP); adenylate energy charge (AEC)), organic acids (lactic acid (LA); short chain fatty acids (SCFA)) and pH at twelve sites of the GI tract. The microbial activity as measured by the ATP concentration was low in the stomach and the cranial two-thirds of the small intestine, but tended to increase in the distal third. In the caecum a sharp rise in microbial activity was observed; the highest level was found for the diet providing most fermentable substrates. In all the diets but the rolled oats+oat bran diets, microbial activity showed a descending pattern as the digesta moved through the colon. In the large intestine source and level of residues had a marked influence on microbial activity. LA was the chief organic acid in the stomach and small intestine (10–40 mmol/l) while LA relative to SCFA was a minor component in the caecum and colon (10–20 mmol/l). The contribution of SCFA to total organic acids was reciprocal to LA, i. e. low in the stomach and small intestine (<20 mmol/l) and high in the caecum and colon. In the large intestine the concentration of SCFA decreased from 100–140 mmol/l in the caecum and proximal colon to 40–80 mmol/l in the distal colon. The acetic: propionic acid ratio increased from the caecum to the distal colon. With the diets based on oat alone (rolled oats; rolled oats+oat bran) the increase was less significant. DF addition and oats in particular increased the butyric acid molar ratio, from 0.06–0.08 for the wheat flour diet to 0.10–0.12 for the diet based on rolled oats+oat bran. For the same two diets the proportion of isobutyric and isovaleric acids increased more rapidly with the wheat-flour diet compared with the rolled oats+oat bran diet.

Background. Oat (Avena sativa L.) is one of the most important sources of protein, oil, starch and dietary fibers, in particular β-glucans. Dietary fiber serves as a source of nutrition for the intestinal microflora and significantly affects not only its composition, but also the normal functioning of the intestine as a whole. In connection with the increased interest in β-glucans as a food component and dietary supplement, there is a need in a convenient and inexpensive method for determination of β-glucans content in grain. The article provides an overview of the existing methods for the isolation and determination of soluble β-glucans in cereals: enzymatic, alkaline, alkaline-enzymatic, colorimetric; their advantages and disadvantages are noted. The main disadvantages of some methods are the complexity and duration of execution, significant cost of the required reagents, and the inability to determine the exact content of β-glucans due to their insufficient purification from various impurities.Results. This study used the example of naked and covered oat cultivars to demonstrate applicability of the gravimetric method that we developed by modifying the alkaline method. Whole grain oat flour was pretreated with a 50% ethanol solution to inactivate β-glucanase and remove free sugars, some lipids, proteins, and other substances. β-glucans were released from the aleurone layer and the endosperm with a 5% sodium hydroxide solution, and finally extracted with a 70% ethanol solution. Β-glucans floated to the surface in the form of a bunch of fibers, which was then dried at a temperature about 100-102°C to constant weight and weighed. The content of β-glucans was calculated from the dry weight (%). The isolated β-glucans were checked for the presence of accompanying substances: the content of nitrogenous substances was determined by the Kjeldahl method, and the presence of starch was determined by a qualitative reaction with Lugolʼs reagent.Conclusions. The content of β-glucans in the grain of the studied samples ranged from 3.12±0.18 up to 4.65±0.17% of the dry weight. As a result of the study, the optimal conditions of β-glucans isolation were selected: the extraction mixtures ratios, as well as the modes of centrifugation, sedimentation and drying were established. It has been shown that this method makes it possible to isolate β-glucans with a minimum impurity of nitrogenous substances (0.07-0.12%) and no traces of starch. One of the advantages of the described method is its availability for mass analysis when studying a collection of grain crops.

Les organismes constituant des assemblages d’ennemis naturels des herbivores peuvent interagir de façon variable, influençant ainsi l’efficacité de la lutte biologique. En serriculture, la mouche blanche, Trialeurodes vaporariorum est effectivement contrôlée par une gamme d’ennemis naturels dont le prédateur zoophytophage, Dicyphus hesperus, le champignon entomopathogène Beauveria bassiana et le parasitoïde Encarsia formosa. Cette étude explore les interactions entre ces agents afin d’identifier celles qui sont efficaces. En laboratoire, la capacité discriminatoire du prédateur D. hesperus envers des proies saines, parasitées ou infectées a été étudiée. Le prédateur attaque tant les proies saines que les proies parasitées par E. formosa, mais rejette les proies présentant des symptômes d’infection avancée par B. bassiana. En serre expérimentale, l’impacte de B. bassiana sous sa formule commercialisée de BotaniGard® sur la lutte biologique a été évaluée pendant une saison de production de huit semaines. Une réduction la de prédation des mouches blanches par D. hesperus suggère que ce pathogène interfère avec le prédateur, ce qui pourrait être evité par l’aménagement de refuges dans l’espace et dans le temps pour le prédateur, lors de l’utilisation de B. bassiana.<br>In Canada, an increasing diversity of natural enemies, which includes generalist predators, is available in the control of greenhouse pests such as the greenhouse whitefly on tomato crops. Successful whitefly suppression is now achieved through the concurrent use of the specialist parasitoid Encarsia formosa, the native zoophytogphagous predatory bug Dicyphus hesperus and products such as biological insecticide BotaniGard®, an entomopathogenic formulation based on the conidia of fungus Beauveria bassiana strain GHA. In this study, experiments conducted in the laboratory and greenhouse evaluated the impact of interactions among these organisms on non-target organisms. In the laboratory, we identified an important decrease in predation of infected whitefly at late infection stages, but not of parasitized whitefly suggesting that D. hesperus may interfere with parasitoid biological control. In the greenhouse, reduced predation of B. bassiana infected whitefly by D. hesperus may be avoided by applying temporal or spatial separation between these two agents.

Au Québec, le dépérissement des fraisières cultivées (Fragaria x ananassa Duchesne) observé dernièrement a principalement été causé par les virus SMYEV, SCV, SMoV, SVBV et SPaV. Les vecteurs sont le puceron du fraisier, Chaetosiphon fragaefolii (Cockerell), et l’aleurode des serres, Trialeurodes vaporariorum (Westwood). Cette étude de deux ans comportait six objectifs. Premièrement, nous avons comparé l’efficacité de deux outils de dépistage des vecteurs, soit les pièges-collants jaunes et les pièges-bols jaunes. Les résultats démontrent que les pièges-collants sont plus efficaces pour la capture de pucerons et d’aleurodes, toutes espèces confondues. Deuxièmement, nous avons déterminé les périodes de vol des deux insectes vecteurs à l’échelle provinciale. Les résultats indiquent que le puceron du fraisier est principalement présent dans les champs du début juillet jusqu’au début septembre. Quant à l’aleurode des serres, il est présent de début juin jusqu’à la fin octobre. Troisièmement, nous avons évalué la prévalence des virus SMYEV et SCV dans les spécimens de pucerons du fraisier ailés capturés. Des analyses RT-PCR ont démontré que 38% des pucerons (N=205) étaient infectés. Le quatrième objectif consistait à évaluer la capacité des fraisiers sauvages (Fragaria virginiana Miller) à constituer un réservoir naturel de virus. Les analyses RT-PCR ont indiquées que 67% des talles de fraisierssauvages (N=12) étaient infectées et qu’elles représentent donc des réservoirs de virus. Le cinquième objectif était de suivre l’accumulation des virus dans 14 fraisières à l’aide de plants sentinelles protégés et exposés. Les résultats confirment que les plants de fraisier exposés en plein champ ont accumulé des virus suite aux envolées des vecteurs. Enfin, nous avons réalisé un inventaire considérable des différentes espèces de pucerons et d’aleurodes retrouvées en fraisières. Cette étude a apporté d’importantes contributions dans la gestion des insectes vecteurs de virus dans le cadre de la problématique du dépérissement des fraisières au Québec.<br>Au Québec, le dépérissement des fraisières cultivées (Fragaria x ananassa Duchesne) observé dernièrement a principalement été causé par les virus SMYEV, SCV, SMoV, SVBV et SPaV. Les vecteurs sont le puceron du fraisier, Chaetosiphon fragaefolii (Cockerell), et l’aleurode des serres, Trialeurodes vaporariorum (Westwood). Cette étude de deux ans comportait six objectifs. Premièrement, nous avons comparé l’efficacité de deux outils de dépistage des vecteurs, soit les pièges-collants jaunes et les pièges-bols jaunes. Les résultats démontrent que les pièges-collants sont plus efficaces pour la capture de pucerons et d’aleurodes, toutes espèces confondues. Deuxièmement, nous avons déterminé les périodes de vol des deux insectes vecteurs à l’échelle provinciale. Les résultats indiquent que le puceron du fraisier est principalement présent dans les champs du début juillet jusqu’au début septembre. Quant à l’aleurode des serres, il est présent de début juin jusqu’à la fin octobre. Troisièmement, nous avons évalué la prévalence des virus SMYEV et SCV dans les spécimens de pucerons du fraisier ailés capturés. Des analyses RT-PCR ont démontré que 38% des pucerons (N=205) étaient infectés. Le quatrième objectif consistait à évaluer la capacité des fraisiers sauvages (Fragaria virginiana Miller) à constituer un réservoir naturel de virus. Les analyses RT-PCR ont indiquées que 67% des talles de fraisierssauvages (N=12) étaient infectées et qu’elles représentent donc des réservoirs de virus. Le cinquième objectif était de suivre l’accumulation des virus dans 14 fraisières à l’aide de plants sentinelles protégés et exposés. Les résultats confirment que les plants de fraisier exposés en plein champ ont accumulé des virus suite aux envolées des vecteurs. Enfin, nous avons réalisé un inventaire considérable des différentes espèces de pucerons et d’aleurodes retrouvées en fraisières. Cette étude a apporté d’importantes contributions dans la gestion des insectes vecteurs de virus dans le cadre de la problématique du dépérissement des fraisières au Québec.<br>In Quebec, strawberry decline disease outbreak occurring in strawberry fields (Fragaria x ananassa Duchesne) has been predominantly caused by viruses (SMoV, SVBV, SPaV, SMYEV and SCV). The vectors are the strawberry aphid, Chaetosiphon fragaefolii (Cockerell) (Hemiptera: Aphididae) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera : Aleyrodidae). This 2-year study had six objectives. First, we compared the effectiveness of two screening techniques, yellow sticky traps and yellow pan-traps. The results demonstrated that the yellow sticky traps are more effective for capturing aphids and whiteflies, all species combined. The second objective was to determine the flight periods of the main vectors across the province. The results indicated that the winged strawberry aphids are mainly present in strawberry fields from early July until early September. As for the greenhouse whitefly, it is mainly present from early June and extends through October. The third objective was to measure the prevalence of SMYEV and SCVin winged strawberry aphid specimens captured in 2014 and 2015. The RT-PCR results indicated that 38% of the aphids (N=205) captured were infected. The fourth objective was to examine the ability of wild strawberries (Fragaria virginiana Miller) to be a long-term host for strawberry viruses. The RT-PCR results demonstrated that 67% of the wild strawberry patches tested (N=12) were infected and therefore, represent a natural reservoir. The fifth objective was to monitor the viruses’ accumulation in 14 strawberry fields throughout the province, using protected and exposed control plants. The results confirmed that the exposed control strawberry plants accumulated viruses following the vectors’ flights over the season. Finally, we carried out a considerable inventory of the different species of aphids and whiteflies found in strawberries. This study has provided important contributions to the management of virus-carrying insects as part of the problem of the strawberry declinein Quebec.<br>In Quebec, strawberry decline disease outbreak occurring in strawberry fields (Fragaria x ananassa Duchesne) has been predominantly caused by viruses (SMoV, SVBV, SPaV, SMYEV and SCV). The vectors are the strawberry aphid, Chaetosiphon fragaefolii (Cockerell) (Hemiptera: Aphididae) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera : Aleyrodidae). This 2-year study had six objectives. First, we compared the effectiveness of two screening techniques, yellow sticky traps and yellow pan-traps. The results demonstrated that the yellow sticky traps are more effective for capturing aphids and whiteflies, all species combined. The second objective was to determine the flight periods of the main vectors across the province. The results indicated that the winged strawberry aphids are mainly present in strawberry fields from early July until early September. As for the greenhouse whitefly, it is mainly present from early June and extends through October. The third objective was to measure the prevalence of SMYEV and SCVin winged strawberry aphid specimens captured in 2014 and 2015. The RT-PCR results indicated that 38% of the aphids (N=205) captured were infected. The fourth objective was to examine the ability of wild strawberries (Fragaria virginiana Miller) to be a long-term host for strawberry viruses. The RT-PCR results demonstrated that 67% of the wild strawberry patches tested (N=12) were infected and therefore, represent a natural reservoir. The fifth objective was to monitor the viruses’ accumulation in 14 strawberry fields throughout the province, using protected and exposed control plants. The results confirmed that the exposed control strawberry plants accumulated viruses following the vectors’ flights over the season. Finally, we carried out a considerable inventory of the different species of aphids and whiteflies found in strawberries. This study has provided important contributions to the management of virus-carrying insects as part of the problem of the strawberry declinein Quebec.<br>Résumé en espagnol<br>Résumé en espagnol