References of "Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE]"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailEvaluation of observer effect in botanical surveys of grasslands
Couvreur, Jean-Marc; Fievet, Vincent; Smits, Quentin et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015)

Description of the subject. A field study has been conducted on 24 grasslands with five different botanical experts in order to assess inter-observer bias when making botanical surveys as well as the ... [more ▼]

Description of the subject. A field study has been conducted on 24 grasslands with five different botanical experts in order to assess inter-observer bias when making botanical surveys as well as the possible consequences in terms of descripting a semi-natural habitat. Objectives. Fieldwork has been conducted to understand the most important factors of variability affecting botanical surveys conducted by several observers. These results were used to suggest practical solutions to enhance the quality of such surveys. Method. Five observers performed a complete botanical survey of 24 grassland plots in the Famenne (Wallonia, Belgium) in June 2009. All surveys were statistically analyzed in order to detect and quantify the sources of variability between observers. The main parameters compared are the habitat diagnosis made on the field by the experts, the rate of detection of the characteristic species as well as their coverage in each plot. Results. Regarding habitat identification, the biggest differences between observers are seen in plots where the composition is intermediate between a habitat in good and in bad status. Overall, there was a slight tendency to undervalue the quality of the habitat. The analysis revealed that the primary cause of variability between observers is the fact that the experts did not always strictly follow the criteria for habitat identification. As regards the comparison between observers, several sources of variability were identified. The main ones are the variability of the estimated coverage of some plants, the variability of the detection rate of characteristic species, as well as the variability of the prospecting effort that can be sub-optimal in each plot. Conclusions. Some of the sources of variability that have been pointed out can be resolved easily, other have to be taken in consideration when comparing the results of surveys in the future. The solutions proposed to reduce the variability between observers are to encourage better self-control of the parameters to be taken into account at each step of the work, the organization of targeted training courses and more standardized prospecting efforts. Keywords. Grassland, detection rate, cover rate, observer effect, bias, prospection, monitoring, habitat, identification. [less ▲]

Detailed reference viewed: 21 (2 ULg)
Full Text
Peer Reviewed
See detailNew lipolitic enzymes identified by screening two metagenomic libraries derived from the soil of a winter wheat field
Stroobants, Aurore ULg; Martin, Renée ULg; Roosens, Lyse et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(2), 125-131

Lipolytic enzymes are widely distributed and fulfil important physiological functions in the microorganisms inhabiting diverse environments. Soils are rich, diversified environments containing microbial ... [more ▼]

Lipolytic enzymes are widely distributed and fulfil important physiological functions in the microorganisms inhabiting diverse environments. Soils are rich, diversified environments containing microbial communities that remain largely unknown. [less ▲]

Detailed reference viewed: 67 (0 ULg)
Peer Reviewed
See detailMeliponini and Apini in Africa (Apidae: Apinae): a review on the challenges and stakes bound to their diversity and their distribution
Fabre Anguilet, Edgard ULg; Nguyen, Bach Kim ULg; Bengone Ndong, Toussaint et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(4),

Introduction. Meliponini and Apini contribute to the pollination of flowering plants and to improving agricultural yields. These bees’ diversity, distribution and abundance depend on the ecosystem in ... [more ▼]

Introduction. Meliponini and Apini contribute to the pollination of flowering plants and to improving agricultural yields. These bees’ diversity, distribution and abundance depend on the ecosystem in which they evolve. The present work aims to summarize the diversity, distribution, abundance, potential threats, challenges and issues faced with respect to these social bees in Africa. Literature. In Africa, there were 21 species of Meliponini and 2 species of Apini (Apis). Aspects related to the species diversity, distribution, biology, ecology and abundance of nests are poorly documented, especially for Meliponini. This deficit could be related to a lack of interest of the authors or the various difficulties in performing these studies in Africa. With regard to the difficulties, there is a need to clarify the taxonomy of Meliponini, and the observation of nests in certain forest environments is difficult. Nest predation and habitat loss are the main threats that could cause the depopulation of certain social bee species in Africa. If there is currently new evidence that diseases and pests did not endanger these bees, then there is a need for further studies for better assessment of the risks that are associated with these potential threats. Conclusions. Work on the diversity, distribution and abundance of the social bees must be strengthened to address the challenges that are related to these insects in Africa. Indeed, this approach will contribute to answering the challenges of sustainable management of the biodiversity and economic and agricultural issues. [less ▲]

Detailed reference viewed: 109 (17 ULg)
Full Text
Peer Reviewed
See detailImpact of drying and heat treatment on the feeding value of corn. A review
Odjo, Djosse Psijus Sylvanus ULg; Malumba Kamba, Paul ULg; Beckers, Yves ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2015), 19(3), 301-312

Introduction: Corn is the main cereal cultivated in the world. As feedstuffs for broiler chickens, corn grains provide the majority of the animals’ required metabolizable energy and an appreciable amount ... [more ▼]

Introduction: Corn is the main cereal cultivated in the world. As feedstuffs for broiler chickens, corn grains provide the majority of the animals’ required metabolizable energy and an appreciable amount of protein. However, when submitted to high temperature treatment, such as during drying, the feeding value of corn grain may change significantly. This review reports the current knowledge on changes that occur within corn grains during high temperature drying processes, which can impact on the feeding value of the grains. Literature. Studies show that during these high temperature drying processes, structural changes occur within the major components of corn grains, including starch and proteins, which may affect their bioavailability. These changes may have a significant impact on metabolizable energy and zootechnical performance. Drying could also affect the physical traits of corn grains and in turn the feeding behavior of animals. Conclusions. In spite of the importance of grain drying within the corn grain sector, few studies have been devoted to the effect of drying on the feeding value of corn and no consensus has been reached on this subject, possibly because of the different conditions involved in the experiments reported to date. Strict controls over drying conditions and the use of appropriate methods of analysis for a better appreciation of the effects of drying are therefore recommended. [less ▲]

Detailed reference viewed: 20 (6 ULg)
Full Text
Peer Reviewed
See detailSpeciation in Malagasy lemurs: a review of the cryptic diversity in genus Lepilemur
Wilmet, Leslie ULg; Schwitzer, Christoph; Devillers, Pierre et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(4), 577-588

Madagascar is one of the highest biodiversity hotspots on the planet; however, it is also one of the most heavily impacted countries in the world in terms of forest degradation and general habitat ... [more ▼]

Madagascar is one of the highest biodiversity hotspots on the planet; however, it is also one of the most heavily impacted countries in the world in terms of forest degradation and general habitat destruction. Genus Lepilemur, in family Lepilemuridae, is a genus of small, nocturnal, exclusively arboreal Malagasy folivores. All species in the genus have small ranges of distribution. Fully forest-dependent, they have a high risk of extinction. Various models and theories of speciation mechanisms have been developed for the fauna and flora of Madagascar. For instance, in the northwestern part of the island, some authors used Lepilemur spp. to test two existing models of distribution: the “Martin model” and “Wilmé model”. Regarding the impact of forest destruction and habitat degradation in Madagascar, conservation strategies for Lepilemur need to be put in place. This paper gives an overview of the current knowledge of the genus Lepilemur and examines speciation for Malagasy lemurs. The understanding of species distribution within biodiversity hotspots is important to identify target for conservation. Therefore, we summarize and compare three biogeography models related to lemurs distribution in order to understand the reasons behind the high diversity (26 species in total) among the genus Lepilemur. Particular attention is also given to the concept of species regarding biodiversity issues and the taxonomic explosion in genus Lepilemur. [less ▲]

Detailed reference viewed: 112 (16 ULg)
Full Text
Peer Reviewed
See detailLes porcheries : réservoirs des Culicoides (Diptera: Ceratopogonidae), vecteurs des virus de la Maladie de la Langue bleue et de Schmallenberg ?
Zimmer, Jean-Yves ULg; Saegerman, Claude ULg; Martinelle, Ludovic ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(4), 480-487

La fièvre catarrhale ovine (FCO) est une arbovirose qui affecte les ruminants domestiques et sauvages. Depuis sa récente apparition en Europe du Nord, cette épizootie virale a engendré des pertes ... [more ▼]

La fièvre catarrhale ovine (FCO) est une arbovirose qui affecte les ruminants domestiques et sauvages. Depuis sa récente apparition en Europe du Nord, cette épizootie virale a engendré des pertes économiques considérables. Les vecteurs biologiques du virus de la FCO sont des moucherons piqueurs appartenant au genre Culicoides (Diptera : Ceratopogonidae). Plusieurs campagnes de piégeage lumineux de ces moucherons adultes ont été réalisées précédemment en Belgique au sein d’exploitations bovines et ovines, mais aucune à l’intérieur des exploitations porcines. Cette étude vise donc à évaluer, au moyen de pièges lumineux, les populations de culicoïdes éventuellement présentes à l’intérieur de deux porcheries belges au cours de l’automne et de l’hiver 2008. La présence des espèces (potentiellement) vectrices du genre Culicoides a ainsi été mise en évidence à l’intérieur de ces bâtiments durant l’automne : 8 et 749 spécimens appartenant à 2 et 7 espèces ont ainsi respectivement été piégés au sein des porcheries, avec une majorité de femelles du complexe Obsoletus. L’ouverture des bâtiments semble fortement influencer leur présence. L’observation du statut alimentaire des femelles laisse supposer que ces moucherons sont susceptibles de se nourrir ou de pondre au sein des porcheries, même si le sang de porc n’a pas pu être identifié dans l’abdomen des femelles gorgées et que le lisier n’a pas révélé la présence de larves. Les porcs pourraient ainsi intervenir dans le maintien des populations d’espèces potentiellement vectrices du virus de la FCO, ou du nouveau virus dénommé virus Schmallenberg. [less ▲]

Detailed reference viewed: 73 (20 ULg)
Full Text
Peer Reviewed
See detailThe role of olfaction in wireworms: a review on foraging behavior and sensory apparatus
Barsics, Fanny ULg; Haubruge, Eric ULg; Francis, Frédéric ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(4), 524-535

Introduction Integrated management of wireworms (Coleoptera: Elateridae) depends upon approaches applied both above- and belowground, and over several spatial scales. While foraging, these soil pests use ... [more ▼]

Introduction Integrated management of wireworms (Coleoptera: Elateridae) depends upon approaches applied both above- and belowground, and over several spatial scales. While foraging, these soil pests use biotic and abiotic signals to orientate towards target plant organs. Development of efficient techniques for implementation in integrated strategies relies upon improved knowledge of this process. In particular, an important step consists of elucidating the role of volatile organic compounds (VOC), emitted by belowground plant organs, in wireworm chemical ecology. This would have a positive impact on push-pull strategies and varietal selection developed against these insects. Literature In this work, we summarized the available data regarding wireworm foraging behavior as well as variables that should be considered when studying the potential role of plant-produced volatile semiochemicals. This includes CO2 gradients and other host-related cues, temperature, relative humidity and soil moisture, and wireworm physiological stage. We also review what is known of the sensory apparatus of wireworms, since this is involved in every step of the foraging process. Conclusion Some baseline data for studying VOC related wireworm foraging behavior exists. Using it as a tool in applied entomology should result in discovery of the semiochemicals that underpin trophic interactions involving these pests. However, most of the key pest species are not fully described with regards to the parameters detailed here. Obtaining accurate information to fill the current knowledge gaps will be needed in order to devise new integrated management strategies. [less ▲]

Detailed reference viewed: 66 (15 ULg)
Full Text
Peer Reviewed
See detailPropriétés physico-chimiques et biologiques des substances humiques en relation avec le développement végétal
Tahiri, Abdelghani ULg; Destain, Jacqueline ULg; Druart, Philippe et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(3), 436-445

Les substances humiques (SH) sont des composés organiques résultant de la transformation physique, chimique et microbiologique des résidus végétaux et animaux. Elles se retrouvent sous forme de ... [more ▼]

Les substances humiques (SH) sont des composés organiques résultant de la transformation physique, chimique et microbiologique des résidus végétaux et animaux. Elles se retrouvent sous forme de macromolécules carbonées hétérogènes et complexes dans tous les écosystèmes au niveau des sols ainsi que des sédiments, des eaux de surface et des lixiviats de décharges. Elles sont issues de processus d’humification déférents, générant ainsi des molécules variables et complexes composées principalement de carbone, d’hydrogène, d’oxygène, d’azote, de soufre et de groupements fonctionnels (COOH, OH, C=O). Ces substances sont connues pour influencer les propriétés du sol et interagir avec la croissance et le développement des plantes ou avec l’activité des microorganismes. L’influence de la croissance des plantes s’exprime généralement de manière directe via la stimulation des processus biochimiques et métaboliques ou indirecte via l’amélioration de la nutrition minérale. Mais, l’intensité de réponse reste dépendante de différents paramètres tels que l’origine, la nature de la matière organique initiale, les processus de transformation et la concentration des SH ainsi que des conditions expérimentales et des plantes traitées. Les mécanismes par lesquels les SH exercent leurs effets favorables sur les végétaux sont imprécis et généralement pas bien compris. [less ▲]

Detailed reference viewed: 32 (7 ULg)
Full Text
Peer Reviewed
See detailNon-isothermal moisture balance equation in porous media: a review of mathematical formulations in Building Physics
Dubois, Samuel ULg; Lebeau, Frédéric ULg; Evrard, Arnaud ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(3),

Understanding heat and mass transfers in porous materials is crucial in many areas of scientific research. Mathematical models have constantly evolved, their differences lying mainly in the choice of the ... [more ▼]

Understanding heat and mass transfers in porous materials is crucial in many areas of scientific research. Mathematical models have constantly evolved, their differences lying mainly in the choice of the driving potentials used to describe moisture flows, as well as in the complexity of characterizing the physical phenomena involved. Models developed in the field of Building Physics (HAM models) are used to describe the behavior of envelope parts and assess their impact on user comfort and energy performance. The water balance equation can be described in many ways; it is a function of the boundary conditions considered and the fact they induce high or low water content in the porous materials used. This paper gives an overview of various formulations for this equation that are found in the Building Physics literature. It focuses first on the physically based formulation of moisture balance, drawing on the Representative Elementary Volume (REV) concept, coupled with thermodynamic flow rates description. This is then reformulated in line with various main moisture state variables offering a wide variety of expressions that are compared with available models. This approach provides access to all secondary transport coefficients associated with the process of mathematical transformation. Particular emphasis is placed on the moisture storage function choice and its impact on the final mathematical formulations. [less ▲]

Detailed reference viewed: 129 (6 ULg)
Full Text
Peer Reviewed
See detailSynthèse bibliographique : l'écologie larvaire des culicoïdes (Diptera : Ceratopogonidae)
Zimmer, Jean-Yves ULg; Haubruge, Eric ULg; Francis, Frédéric ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(2), 301-312

Cet article présente une synthèse de l’écologie larvaire des culicoïdes (Diptera : Ceratopogonidae) en vue de rassembler les connaissances, souvent très parsemées, des sites d’oviposition et des habitats ... [more ▼]

Cet article présente une synthèse de l’écologie larvaire des culicoïdes (Diptera : Ceratopogonidae) en vue de rassembler les connaissances, souvent très parsemées, des sites d’oviposition et des habitats larvaires actuellement identifiés à travers le monde pour les principales espèces de culicoïdes. Ces moucherons piqueurs hématophages sont impliqués dans la transmission de divers parasites (protozoaires et filaires) et virus aux animaux. Le développement larvaire des culicoïdes est généralement optimal dans les substrats humides et riches en débris organiques divers. Cependant, chaque espèce présente ses propres exigences écologiques et se trouve par conséquent dans des micro-habitats spécifiques. Dans cette synthèse, les gites larvaires sont répartis en substrats aquatiques et semi-aquatiques d’eau douce et d’eau salée ou saumâtre, substrats terrestres et substrats anthropiques liés à l’élevage. Les gites larvaires de nombreuses espèces appartenant au genre Culicoides Latreille demeurent cependant encore méconnus. La connaissance de ces derniers et leur caractérisation sont pourtant essentielles pour permettre la mise au point de stratégies de lutte efficaces contre ces insectes vecteurs, permettant ainsi de renforcer la vaccination du bétail et les autres moyens de lutte mis en oeuvre. Les habitats larvaires actuellement identifiés pourraient permettre d’orienter les investigations des recherches écologiques futures et les propositions de contrôle de ces moucherons vecteurs. [less ▲]

Detailed reference viewed: 71 (12 ULg)
Full Text
Peer Reviewed
See detailSynthèse bibliographique sur la mobilité des éléments traces dans les sols et l’utilisation de la stabilisation physico-chimique comme technique de gestion in situ des sites contaminés
Liénard, Amandine ULg; Colinet, Gilles ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(2), 273-289

Industrial activities have deeply impacted the quality of biophysical environment at places. This review focuses on consequences of soil contaminations by metallic trace elements: what conditions the ... [more ▼]

Industrial activities have deeply impacted the quality of biophysical environment at places. This review focuses on consequences of soil contaminations by metallic trace elements: what conditions the mobility of contaminants in soils and what are the remediation practices based upon physico-chemical stabilization? This technique is an in situ remediation which aims at limiting the dispersion of metals in the environment by use of soil conditioners and amendments in contaminated sites. First of all, we reviewed the concepts of mobility of trace elements and their indicators. Then, we compiled the different kinds of amendments applied to stabilize contaminants in soils and the processes involved. [less ▲]

Detailed reference viewed: 107 (23 ULg)
Full Text
Peer Reviewed
See detailApport du traitement d'images dans le suivi de l'influence des teneurs en nutriments sur la croissance des lentilles d'eau (Lemna minor)
Tangou Tabou, Thierry ULg; Baya, Dehenould Trésor; Liady, Mouhamadou Nourou Dine ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(1), 37-48

The growth of duckweed (Lemna minor) is an important component in the process in wasterwater floating macrophyte ponds. An excess or shortage of this biomass may be responsible for the dysfunction of such ... [more ▼]

The growth of duckweed (Lemna minor) is an important component in the process in wasterwater floating macrophyte ponds. An excess or shortage of this biomass may be responsible for the dysfunction of such ponds. Modeling these duckweed ponds through mass balances based on Petersen's matrix may be helpful in facilitating the optimal management of such facilities. This study sought at assessing the efficiency of digital image processing in the growth monitoring of Lemna minor under different concentration of nitrogen and phosphorus. The experiments were carried out in a growth chamber (phytotron) using an experimental pilot involving initial fresh Lemna minor biomass (1 g), nitrogen and phosphorus concentration varying between 5 and 64 mg N-NH4+.L-1, and 1 and 24 mg P-PO43-.L-1, respectively. The digital image processing was achieved in addition to gravimetric methods (fresh weight and/or dry weight). Our results showed that image processing method allowed a continuous and non destructive monitoring of duckweeds biomass. The growth of Lemna minor progressively decreases when nitrogen and phosphorus were greater than 16 mg N-NH4+.L-1 and 6 mg P-PO43-.L-1. The maximum growth rate μmax are of the order of 0.07 d-1, the kinetic constants Ks and Ki are respectively 3.83 mg.L-1 and 204 mg L-1 for nitrogen, 1.26 mg.L-1 and 13.3 mg.L-1 for phosphorus. Such results are interesting as they could serve in the optimal management of Lemna minor and the modeling of biological reactors. [less ▲]

Detailed reference viewed: 79 (8 ULg)
Full Text
Peer Reviewed
See detailImpacts of earthworms on soil components and dynamics. A review
Lemtiri, Aboulkacem ULg; Colinet, Gilles ULg; Alabi, Taofic ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18

Earthworm populations are important decomposers contributing to aggregate formation and nutrient cycling processes involving nitrogen cycles, phosphorus and carbon. They are known to influence soil ... [more ▼]

Earthworm populations are important decomposers contributing to aggregate formation and nutrient cycling processes involving nitrogen cycles, phosphorus and carbon. They are known to influence soil fertility by participating to important processes in soil such as soil structure regulation and organic matter dynamics. Earthworms also modify the microbial communities through digestion, stimulation and dispersion in casts. Consequently, changes in the activities of earthworm communities, as a result of soil management practices, can also be used as indicators of soil fertility and quality. It is therefore important to understand how earthworm communities affect soil dynamics. This review adresses the current state of knowledge on earthworm’s impacts on soil structure and soil organic matter (carbon, nitrogen, and phosphorus) dynamics, with special emphasis on the effects of land management practices on earthworm communities. [less ▲]

Detailed reference viewed: 223 (23 ULg)
Full Text
Peer Reviewed
See detailVers une synthèse de la conception et une définition des zones dans le gradient urbain-rural
Andre, Marie ULg; Mahy, Grégory ULg; Lejeune, Philippe ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(1), 61-74

The increasing footprint of urbanization on landscapes justifies the study of cities and the zones surrounding them. Paradoxically, the concepts relating to these zones remain unclear. Scientists from ... [more ▼]

The increasing footprint of urbanization on landscapes justifies the study of cities and the zones surrounding them. Paradoxically, the concepts relating to these zones remain unclear. Scientists from different disciplines diverge when defining these zones or their limits; they even often mention the zones without any definition. This practice excludes comparison between studies. By means of bibliographic research, the variety of terms used to describe the different zones composing the urban-rural gradient has been evidenced, as well as the characteristics of the zones themselves. They have been evaluated according to their relative importance and according to a series of criteria. Finally, new definitions for the different zones have been proposed in order to enable their identification in the field. [less ▲]

Detailed reference viewed: 217 (45 ULg)
Full Text
Peer Reviewed
See detailIsolation of an amylolytic chrysophyte, Poterioochromonas sp. from the digestive tract of the termite R. santonensis
Tarayre, Cédric ULg; Bauwens, Julien ULg; Brasseur, Catherine ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(1),

The aim of this work was the isolation and cultivation of amylolytic protists living in the digestive tract of the termite Reticulitermes santonensis (Feytaud). A chrysophyte identified as ... [more ▼]

The aim of this work was the isolation and cultivation of amylolytic protists living in the digestive tract of the termite Reticulitermes santonensis (Feytaud). A chrysophyte identified as Poterioochromonas sp. was isolated in a special medium containing rice grains as a source of carbon and nitrogen. Then, the protist was grown in a medium containing starch as a carbon source, tryptone, and a phosphate buffer at different pH values (5, 6 and 7). Yeast extract was added or not. Ciprofloxacin was used to avoid the bacterial development. Other antibiotics were also tested but showed an inhibitive effect on the growth of Poterioochromonas sp. Yeast extract allowed reaching 1.9 (pH 5), 2.3 (pH 6) and 2.2 (pH 7) times higher final cell concentrations, and 2.8 (pH 5), 2.8 (pH 6) and 2.2 (pH 7) times higher biomass yields. The starch concentration did not decrease in the medium until 3 and 4 days of culture, with and without yeast extract, respectively. Eight days of culture were necessary for hydrolyzing the starch completely, with and without yeast extract. Maltose and maltotriose were detected in the culture media and were hydrolyzed progressively. Maximal maltose concentrations were 0.68, 0.66 and 0.51 g.l-1 in the medium containing yeast extract. Maltotriose concentrations were only 0.17, 0.14 and 0.12 g.l-1. Other glucose oligomers were also detected but in lower quantities. It was determined that the protist developed a weak amylase activity, particularly at a weakly acidic pH (5-6). Such a pH also allowed a better growth of the protist. A maximal amylase activity of 112 nkat.l-1 was measured with yeast extract at pH 5. No other enzymatic activity (protease, cellulase or xylanase) was detected except amylase. The degradation products of starch which were obtained by enzymatic hydrolysis allow the identification of α-amylase, amyloglucosidase and possibly β-amylase activities. [less ▲]

Detailed reference viewed: 124 (26 ULg)
Full Text
Peer Reviewed
See detailInfluence de l'environnement et des pratiques culturales sur la productivité de Jatropha curcas L. en Afrique subsaharienne (synthèse bibliographique)
Minengu, Jean de Dieu; Mobambo, Patrick; Mergeai, Guy ULg

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(2), 290-300

In most sub-Saharan African countries, the establishment of Jatropha curcas L. plantations preceded the scientific investigations necessary to optimize the production of this species. Consequently, the ... [more ▼]

In most sub-Saharan African countries, the establishment of Jatropha curcas L. plantations preceded the scientific investigations necessary to optimize the production of this species. Consequently, the development of the plants was low and yields during the first years of cultivation were mostly disappointing. The low yields obtained in marginal conditions led to the belief that the cultivation of Jatropha could only be profitable in areas with fertile soils and sufficiently humid climates, which would place the plants in direct competition with food production. This article analyzes the available scientific knowledge regarding the ecological and technical factors influencing the productivity of J. curcas and suggests possible solutions for improving its performance in sub-Saharan Africa. [less ▲]

Detailed reference viewed: 36 (6 ULg)
Full Text
Peer Reviewed
See detailUse of camera traps for wildlife studies: a review
Trolliet, Franck ULg; Vermeulen, Cédric ULg; Huynen, Marie-Claude ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(3), 446-454

As human threats continue to impact natural habitats, there is an increasing need to regularly monitor the trends in large vertebrate populations. Conservation efforts must be directed appropriately, but ... [more ▼]

As human threats continue to impact natural habitats, there is an increasing need to regularly monitor the trends in large vertebrate populations. Conservation efforts must be directed appropriately, but field work necessary for data collection is often limited by time and availability of people. Camera traps are used as an efficient method to insure permanent sampling and to work in difficult to access areas. In the present study, we illustrate the way the use of camera traps developed: firstly with the need to monitor tiger (Panthera tigris (Linnaeus 1758)) populations and later as an instrument serving a diverse field of studies, such as animal behaviour and fauna-flora interaction. By looking at the material and technical aspects of various models of camera trap for implementation in different field studies in animal ecology, we highlight the need to choose appropriate camera trap models for the target species and to set up solid sampling protocols in order to successfully achieve study objectives. [less ▲]

Detailed reference viewed: 274 (66 ULg)
Full Text
Peer Reviewed
See detailLes indicateurs de la pression du cerf élaphe sur la végétation du sous-bois en forêts feuillues tempérées : synthèse bibliographique
Lehaire, François ULg; Ligot, Gauthier ULg; Morelle, Kevin ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(2), 262-272

During the last decades, the populations of large herbivores have increased. Consequently, their pressure on forest vegetation has been exacerbated and has reached in some forests levels that reduced the ... [more ▼]

During the last decades, the populations of large herbivores have increased. Consequently, their pressure on forest vegetation has been exacerbated and has reached in some forests levels that reduced the diversity of forest ecosystem services. Assessing the balance between timber production and hunting remains a crucial question for forest users (foresters, hunters) and requires reliable tools such as ecological indicators. This paper reviews the ecological indicators that characterize the pressure of red deer (Cervus elaphus L.) on understory vegetation in temperate deciduous forest. Such indicators monitor the cover, height, stem density, biomass and species diversity of different indicator plant groups. These plant groups embrace species belonging to herbaceous stratum, forest regeneration or particular species such as bilberry (Vaccinium myrtillus L.) and bramble (Rubus fruticosus L.). The choice of indicator plants, as it affects considerably the performance of the ecological indicator of deer pressure on understory vegetation, must be carried out with caution taking into account plant abundance and palatability. The reviewed indicators help to understand the relationships between biodiversity, carrying capacity and deer populations. They are intended to forest managers that would like to monitor red deer pressure in regards to forest management goals and forest sustainability. [less ▲]

Detailed reference viewed: 54 (12 ULg)
Full Text
Peer Reviewed
See detailEffets d’amendements carbonatés et organiques sur la culture de deux légumes sur sol contaminé à Lubumbashi (RD Congo)
Mpundu Mubemba, Michel; Useni, Yannick; Nyembo, Lucien et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(3), 367-375

Given the risks of contamination of the vegetables grown in gardens in the city of Lubumbashi due to soil pollution, agronomic solutions to reduce these risks have been experimented. The choice of ... [more ▼]

Given the risks of contamination of the vegetables grown in gardens in the city of Lubumbashi due to soil pollution, agronomic solutions to reduce these risks have been experimented. The choice of appropriate amendments (type and quantity) and the selection of plant varieties able to restrict transfers of trace metals (TM) from the soil to plant edible organs are part of the most conventional remediation techniques. Amaranth and spinach beet have been cultivated in pot trials according to randomized complete blocks with four replications on a contaminated soil that received different doses of liming and/or organic products and slightly contaminated soil. Along with an effect on soil chemistry, the amendments have been effective in reducing the transfer of trace metals from soil to plant. The lime-based treatments were more effective than compost. TM levels in plants however remained high whatever the application of amendments and the question of food chain contamination remains posed. [less ▲]

Detailed reference viewed: 53 (13 ULg)
Full Text
Peer Reviewed
See detailÉtat des lieux des flux céréaliers en Wallonie selon différentes filières d’utilisation
Delcour, Alice ULg; Van Stappen, Florence; Gheysens, Stéphanie et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(2), 181-192

Survey on cereal resources in Wallonia according to their different uses. Survey on cereal resources in Wallonia according to their different uses. More than 60% of the arable cropped area in Wallonia is ... [more ▼]

Survey on cereal resources in Wallonia according to their different uses. Survey on cereal resources in Wallonia according to their different uses. More than 60% of the arable cropped area in Wallonia is dedicated to cereals. Cereal chains were initially aimed at ensuring food security but are now progressively oriented towards new non-food uses. Walloon cereal chains are now having to face up to new global challenges: to ensure the competitiveness and sustainability of vegetal and animal chains, to match society's expectations and to meet the biomass needs for energy uses and bio-based products. Within this framework, this research aims to evaluate the environmental and socio-economic sustainability of future scenarios of current and potential food and non-food uses for Walloon cereals. This paper, the first in a series of two, presents the current picture of Walloon cereal crops and their uses. Various steps are analyzed: production, collection, wholesale and processing. Four main uses characterize cereal processing: the so-called "4Fs", representing Food (human food uses), Feed (animal feed uses), Fuel (energy uses) and Fiber (material uses). Data collected from stakeholders in the Walloon cereal chain enabled us to assess cereal flows for the "4Fs", drawing a qualitative and a quantitative picture of Walloon cereal resources including the key elements of the cereal chains. This approach serves as a basis for a prospective exercise, described in a companion paper, which develops potential uses for Walloon cereal resources at the 2030 horizon. [less ▲]

Detailed reference viewed: 57 (9 ULg)