References of "Brostaux, Yves"
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See detailReproductive ecology of Coula edulis Baill., source of a valuable non-timber forest product
Moupela, Christian ULg; Doucet, Jean-Louis ULg; Daïnou, Kasso ULg et al

in Tropical Ecology (2014), 55(3), 327-338

The reproductive ecology of Coula edulis (Olacaceae), source of a highly valuable non-timber product for African populations, has been investigated on a large tree sample size in a Gabonese forest for a 3 ... [more ▼]

The reproductive ecology of Coula edulis (Olacaceae), source of a highly valuable non-timber product for African populations, has been investigated on a large tree sample size in a Gabonese forest for a 3-year period, in order to propose options for its domestication. Reproduction is annual and the minimum tree diameter for flowering was 10.6 cm while the diameter for regular fructification was 23 cm. The annual diameter increment (ADI; mean = 0.22 cm year-1) was affected by crown exposure, but not by initial tree diameter or fruit production. Tree diameter influenced fruiting frequency and fruit production. There was a strong correlation between fruit production of 2011 and 2012 (Pearson's r = 0.85; P < 0.001), suggesting a high heritability of that trait. Phenotypical selection should be performed prior to any propagation activity. Moreover, as most of C. edulis fruits were sterile (64 %), we propose that sylvicultural strategies should be based on vegetative propagation. [less ▲]

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See detailAssociative learning of Nasonia vitripennis Walker (Hymenoptera: Pteromalidae) to methyldisulfanylmethane
Frederickx, Christine ULg; Verheggen, François ULg; Brostaux, Yves ULg et al

in Journal of Forensic Sciences (2014)

Traditional methods of volatile detection used by police typically consist of reliance on canine olfaction. However, dogs have some limitations such as cost of training and time of conditioning. The ... [more ▼]

Traditional methods of volatile detection used by police typically consist of reliance on canine olfaction. However, dogs have some limitations such as cost of training and time of conditioning. The possibility of using parasitic wasps for detecting explosives and narcotics has been developed. Moreover, wasps are cheap to produce and can be conditioned with impressive speed for a specific chemical-detection task. We examined the ability of Nasonia vitripennis Walker to learn and respond to methydisulfanylmethane (DMDS), a volatile discriminator of cadaver. The training aimed to form an association between an unconditioned stimulus (pupae) and the conditioned stimulus (odor source). After the training, the time spent of conditioned wasps in the DMDS chamber was measured. Statistical analysis showed that the increasing concentrations involved an increase in the time spent in the chamber containing DMDS. This study indicates that N. vitripennis can respond to DMDS, which provide further support for its development as a biological sensor. [less ▲]

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See detailEdible insects acceptance by belgian consumers: promising attitude for entomophagy development
Caparros Megido, Rudy ULg; Sablon, Ludovic; Geuens, Mélodie et al

in Journal of Sensory Studies (2013)

Entomophagy is not well accepted in Western European populations but it is common in the world. In the future, populations from developed countries should adapt to other sources of animal proteins because ... [more ▼]

Entomophagy is not well accepted in Western European populations but it is common in the world. In the future, populations from developed countries should adapt to other sources of animal proteins because traditional breeding of beef, poultry or pork will become unsustainable. This study was performed to assess the perception of entomophagy in the Belgian population. A slight neophobia was detected but people agreed to evaluate insect preparations. Various insect formulations (mealworms and house crickets) were prepared, and insects associated with known flavors and crispy textures were preferred. After a hedonic test, people seemed to be willing to eat and cook insects in the near future. The opportunity to introduce entomophagy in food habits of Western Euro- pean populations was positively concluded. Integration of edible insects in human food is a potential solution to replace other animal protein sources in a much more sustainable development and will deserve more attention in the future. [less ▲]

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See detailUse of response surface methodology for the optimization of the lipase-catalyzed synthesis of mannosyl myristate in pure ionic liquid
Galonde, Nadine ULg; Brostaux, Yves ULg; Richard, Gaetan ULg et al

in Process Biochemistry (2013), 48(11), 1914-1920

The purpose of the present study is to find the conditions allowing to reach the highest 24 h-yield(24 h- ) for the synthesis of mannosyl myristate catalyzed by the immobilized lipase B from Candida ... [more ▼]

The purpose of the present study is to find the conditions allowing to reach the highest 24 h-yield(24 h- ) for the synthesis of mannosyl myristate catalyzed by the immobilized lipase B from Candida antarctica (Novozym®435) in the ionic liquid (IL) [Bmpyrr][TFO] (1-butyl-1-methylpyrrolidinium tri-fluoromethanesulfonate). A full factorial design (FFD) was used in order to study the influence of three variables (temperature, mannose/vinyl myristate ratio and total substrate quantity) on the 24 h- . This design led to a model based on a second order polynomial response function. The resulting predicted con-tour plots have shown that the highest 24 h- should be obtained with high temperatures, low sugar/vinylester molar ratio and intermediate total substrate quantities (mmol). The model has been successfully verified and experimentally confirmed at the optimal conditions of 80◦C, substrate molar ratio of 1/10and total substrate quantity of 0.26 mmol leading to the highest predicted 24 h- of 72.2%. [less ▲]

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See detailTest modeling of the growth of self-fertilized embryos of Phaseolus vulgaris L. and Phaseolus coccineus L. genotypes
Nguema Ndoutoumou, Pamphile; Boussiengui Boussiengui, Gino; Ngakou, Albert et al

in African Journal of Plant Science (2013), 7(8), 310-316

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See detailHow closely are Pericopsis elata (Fabaceae) patches linked to past human disturbances in South-Eastern Cameroon
Bourland, Nils ULg; Cerisier, François; Daïnou, Kasso ULg et al

Conference (2013, June 26)

Studies conducted in the Congo Basin forests concluded that soil parameters and large disturbances induced by human activities since 3000–2000 BP could be the main driver for the persistence of long lived ... [more ▼]

Studies conducted in the Congo Basin forests concluded that soil parameters and large disturbances induced by human activities since 3000–2000 BP could be the main driver for the persistence of long lived light-demanding tall tree species. Today most of the timber species belong to this group, among them Pericopsis elata (Fabaceae). Like many other light-demanding trees, this species suffers from important regeneration problems. While the conditions for its establishment must have been met in the past, they obviously have become unfavourable. Because of ongoing logging activities and a natural decline of its populations, this species is recorded in both the IUCN Red List and the CITES Appendix II listings. Our goal was to investigate the roles of both pedological and anthropogenic factors in the persistence of forest patches characterized by this clustered species. Soil surveys, botanical inventories and anthracological excavations were conducted in three different forest sites located in south-eastern Cameroon. P. elata patches (3.3-14.7 ha) were studied and compared to their close surroundings. No statistical differences were observed between the results of botanical inventories conducted inside and outside the patches (Morisita-Horn indices from 0.69-0.77). Soils only differed in Fe content, but otherwise no significant differences could be observed. Charcoal is widespread and abundant in study sites, mostly inside the patches. Charcoal radiocarbon dating (2,150-195 BP) was consistent with decoration techniques of archaeological materials that we discovered. The average age of P. elata individuals coincides with fire events that occurred in a region where fires rarely occur naturally. We present evidence of past anthropogenic disturbances (human settlement, slash-and-burn cultivation) in the Congolese mixed moist semi-evergreen forest in south-eastern Cameroon. We discuss the potential influence of our findings on the management of light-demanding tall trees populations in a context of logging activities. [less ▲]

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See detailModelling the top-height growth and site index of Norway spruce in Southern Belgium
Perin, Jérôme ULg; Hebert, Jacques ULg; Brostaux, Yves ULg et al

in Forest Ecology & Management (2013), 298

Top-height growth in even-aged stands of Norway spruce (Piceaabies (L.) Karst.) from Southern Belgium was modelled using functions which provide an algebraic solution for site index (SI) calculation. 16 ... [more ▼]

Top-height growth in even-aged stands of Norway spruce (Piceaabies (L.) Karst.) from Southern Belgium was modelled using functions which provide an algebraic solution for site index (SI) calculation. 16 well known growth model formulations were parameterized using a method which accounts for heterogeneous variance and autocorrelation on a dataset composed of stem analysis data completed by measuring the heights of all the branch whorls to allow for accurate height–age estimates. Comparison of the parameterized models showed that the oblique asymptotic function known as the Duplat and Tran-Ha III model was the most efficient on our dataset. Validation of the selected model on permanent sample plot data showed no evidence of bias over the full range of possible age, height, site index and densities encountered in Norway spruce stands of Southern Belgium. The new height growth model described represents a significant improvement over the previous model of Dagnelie et al. (1988), which was found to be unreliable and required the use of an iterative process to estimate SI. [less ▲]

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See detailElectrophysiological and behavioural responses of Thanatophilus sinuatus F. (Coleoptera: Silphidae) to selected cadaveric volatile organic compounds
Dekeirsschieter, Jessica ULg; Frederickx, Christine ULg; Lognay, Georges ULg et al

in Journal of Forensic Sciences (2013)

Soon after death, carcasses release volatile chemicals that attract carrion insects including Silphidae. Nevertheless, it is not known which chemical cues are involved in the attractiveness of the carcass ... [more ▼]

Soon after death, carcasses release volatile chemicals that attract carrion insects including Silphidae. Nevertheless, it is not known which chemical cues are involved in the attractiveness of the carcass. So far, little information is available on the chemical ecology of carrion beetles, particularly concerning the subfamily of Silphinae. The biological role of selected cadaveric volatile organic compounds including: dimethyldisulfide (DMDS), butan-1-ol, n-butanoic acid, indole, phenol, p-cresol, putrescine, and cadaverine on the silphine species, Thanatophilus sinuatus Fabricius, was investigated by using both electrophysiological and behavioural techniques. Among the tested cadaveric compounds, butan-1-ol and DMDS elicited the strongest EAG from both T. sinuatus male and female antennae. In a two-arm olfactometer, males and females were significantly attracted to dimethyldisulfide (DMDS) for both tested doses, whereas only males were attracted to p-cresol at 100 ng. Putrescine was repellent to males at the dose of 1 µg [less ▲]

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See detailPropensity of the Tomato Leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), to Develop on Four Potato Plant Varieties
Caparros Megido, Rudy ULg; Brostaux, Yves ULg; Haubruge, Eric ULg et al

in American Journal of Potato Research (2013), 90

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is now considered to be one of the most damaging invasive pests of tomatoes in the world. Tomato is regarded as the main host of T. absoluta ... [more ▼]

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), is now considered to be one of the most damaging invasive pests of tomatoes in the world. Tomato is regarded as the main host of T. absoluta, but the pest can also feed, develop and reproduce on other cultivated Solanaceae, such as potato (Solanum tuberosum L). In the present study, we examined the ability of T. absoluta to develop on four commonly cultivated varieties of potato, under laboratory conditions. The survival rate of T. absoluta did not differ between the five tested host plants (tomato: Solanum lycopersicum cv. Moneymaker; and potato: Solanum tuberosum cv. Spunta, Charlotte, Nicola, and Bintje), but its development time (egg to pupation) was significantly affected. Compared to tomato, development times were longer on Bintje and shorter on Nicola, Charlotte, and Spunta. These results show the high capacity of T. absoluta to develop on potato crops. [less ▲]

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See detailInfluence of processing parameters on physicochemical properties of low-trans and trans-free puff pastry margarines
Lefebure, Emilie ULg; Ronkart, Sébastien; Brostaux, Yves ULg et al

in LWT - Food Science and Technology (2013), 51(1), 225-232

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See detailMedium effects on micropropagation and genetic stability of Citrullus lanatus oleaginous type
Gnamien, Yah Gwladys; Zoro Bi, Irié Arsène; Kouadio, Yatty Justin et al

in Agricultural Sciences (2013), 04(07), 32-44

To regenerate adventitious shoots from the cotyledon proximal parts of Citrullus lanatus (Thunb.) Matsum. and Nakai ssp. mucosospermus (Fursa) oleaginous type, different concentrations of MS mineral ... [more ▼]

To regenerate adventitious shoots from the cotyledon proximal parts of Citrullus lanatus (Thunb.) Matsum. and Nakai ssp. mucosospermus (Fursa) oleaginous type, different concentrations of MS mineral elements, sucrose, 6-benzylaminopurine (BAP) and agar were tested. Shoot induction proved to depend on the interaction between levels of sucrose, BAP and MS mineral elements in the medium. The medium containing 3/2 strength of MS mineral elements, 35 g/l sucrose and 1 mg/l BAP solidified with 6 g/l agar allowed the production of numerous shoots without a callus phase. After 3 weeks of culture, 76.7% of the cotyledon proximal parts induced shoots with an average of 12.26 shoots per explant and a mean shoot length of 17.13 mm. The induced shoots were directly rooted and thus complete plants ready for acclimatization were obtained using a two steps procedure. Depending on the genotype, the shoot induction from cotyledon proximal parts ranged from 54% to 96%. Rooted plantlets were acclimatized and transferred to field, where they grew well, developed flowers and fruits like seeded plants. The assessment of the genetic stability of the in-vitro-regenerated plantlets by means of an Amplified Fragment Length Polymorphism (AFLP) analysis with the combination of 5 primers revealed no differences between regenerated plantlets and mother plants. [less ▲]

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See detailImpact of the extension of black leaf streak disease on banana susceptibility to post-harvest diseases
Ewané, Cécile Annie; Chillet, Marc; Castelan, Florence et al

in Fruits (2013), 68(5), 351-365

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See detailThe susceptibility of bananas to crown rot disease is influenced by geographical and seasonal effects
Ewane, Cécile Annie; Lassois, Ludivine ULg; Lepoivre, Philippe ULg et al

in Canadian Journal of Plant Pathology = Revue Canadienne de Phytopathologie (2013), 35(1), 27-36

Crown rot of banana fruits is caused by a complex of fungal pathogens, the most common of which is Colletotrichum musae, and is one of the main quality defects of exported bananas. Susceptibility of ... [more ▼]

Crown rot of banana fruits is caused by a complex of fungal pathogens, the most common of which is Colletotrichum musae, and is one of the main quality defects of exported bananas. Susceptibility of banana fruits to crown rot is influenced by many pre-harvest factors. The aim of this study was to improve on the methodology for the evaluation of fruit susceptibility and to verify whether cultivation areas in Cameroon as well as seasonal variations have an influence on the susceptibility to crown rot. Fruit susceptibility was evaluated on a monthly basis throughout a year (including the dry and rainy seasons) in three banana plantations located at very different agro-ecological conditions (two in a lowland area and one in a highland area). Fruit susceptibility was determined through an internal necrotic surface (INS) assessment after artificial inoculation with C. musae. The standardization of post-inoculation environmental conditions enabled more reliable INS assessments. Fruit susceptibility was found to be significantly influenced by cultivation area (P<0.001) since fruits grown in low altitude (Dia-dia, Koumba, 80 m) were more susceptible than fruits grown in high altitude (Ekona, 500 m). Although no seasonal effect was observed (P=0.075), there was a highly significant date effect (P<0.001). This was specifically the case in low altitude plantations where fruit susceptibility was higher for some harvest dates within the rainy season. In Ekona, fruit grade and number of leaves on the banana plant were found to be significantly higher than in the two other locations, while black leaf streak disease severity was significantly lower. The potential relationship with fruit susceptibility is fully discussed. [less ▲]

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See detailThe susceptibility of bananas to crown rot disease is influenced by geographical and seasonal effects
Ewane, Cécile Annie; Lassois, Ludivine ULg; Lepoivre, Philippe ULg et al

in Canadian Journal of Plant Pathology = Revue Canadienne de Phytopathologie (2013), 35(1), 27-36

Crown rot of banana fruits is caused by a complex of fungal pathogens, the most common of which is Colletotrichum musae, and is one of the main quality defects of exported bananas. Susceptibility of ... [more ▼]

Crown rot of banana fruits is caused by a complex of fungal pathogens, the most common of which is Colletotrichum musae, and is one of the main quality defects of exported bananas. Susceptibility of banana fruits to crown rot is influenced by many pre-harvest factors. The aim of this study was to improve on the methodology for the evaluation of fruit susceptibility and to verify whether cultivation areas in Cameroon as well as seasonal variations have an influence on the susceptibility to crown rot. Fruit susceptibility was evaluated on a monthly basis throughout a year (including the dry and rainy seasons) in three banana plantations located at very different agro-ecological conditions (two in a lowland area and one in a highland area). Fruit susceptibility was determined through an internal necrotic surface (INS) assessment after artificial inoculation with C. musae. The standardization of post-inoculation environmental conditions enabled more reliable INS assessments. Fruit susceptibility was found to be significantly influenced by cultivation area (P<0.001) since fruits grown in low altitude (Dia-dia, Koumba, 80 m) were more susceptible than fruits grown in high altitude (Ekona, 500 m). Although no seasonal effect was observed (P=0.075), there was a highly significant date effect (P<0.001). This was specifically the case in low altitude plantations where fruit susceptibility was higher for some harvest dates within the rainy season. In Ekona, fruit grade and number of leaves on the banana plant were found to be significantly higher than in the two other locations, while black leaf streak disease severity was significantly lower. The potential relationship with fruit susceptibility is fully discussed. [less ▲]

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See detailModeling recent bark stripping by red deer (Cervus elaphus) in South Belgium coniferous stands
Ligot, Gauthier ULg; Gheysen, Thibaut; Lehaire, François ULg et al

in Annals of Forest Science : a Multidisciplinary and International Journal (2013), 70(3),

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See detailOccurrence of Harmonia axyridis (Coleoptera: Coccinellidae) in field crops
Vandereycken, Axel ULg; Brostaux, Yves ULg; Joie, Emilie ULg et al

in European Journal of Entomology (2013), 110(2),

Abstract. The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of ... [more ▼]

Abstract. The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of this exotic species and its seasonal abundance in various field crops. The abundance of adults, larvae and pupae of H. axyridis was evaluated over a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. From May to September, 48 1-m² quadrats were visually inspected in each of the fields sampled on several farms every seven days. H. axyridis colonized and reproduced in all of the four crops studied, with the largest numbers recorded in corn and broad bean crops. Larvae and adults of H. axyridis were recorded mainly in corn and to a much less extent in wheat and potato crops. From 2009 to 2011, the mean weekly abundance of H. ayxridis remained constant except in corn crops, where the recorded densities of all the immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis are well described by a symmetric logistic function (S-shape) of cumulative population size. H. axyridis was not always recorded where aphids were abundant, e.g. aphids were abundant on wheat where no H. axyridis were recorded. H. axyridis start reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of the same and other species of ladybird and other aphidophagous species. H. axyridis is often considered to be bivoltine but it only completes one generation per year in field crops. The second generation generally develops late in the season in other habitats. [less ▲]

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See detailDEVELOPMENT OF FROZEN-FRIED YAM SLICES: OPTIMIZATION OF THE PROCESSING CONDITIONS
Toure, Yetioman ULg; Nindjin, Charlemagne; Brostaux, Yves ULg et al

in African Journal of Food, Agriculture, Nutrition and Development (2012), 12(7), 7055-7071

The research performed on yam processing mainly concerns the production of crisps and flour. However, its transformation into deep-frozen French fries does not necessitate any other equipment than those ... [more ▼]

The research performed on yam processing mainly concerns the production of crisps and flour. However, its transformation into deep-frozen French fries does not necessitate any other equipment than those used for potatoes. The industrial process of production of frozen French fries traditionally includes a pre-frying step. These steps contribute to the development of color and crispness, and the oil partially absorbed inhibits dehydration during the freezing step. The aim of this study was to optimize frying conditions of deep-frozen fried yam (Dioscorea cayenensis var Kponan) slices. The effect of pre-frying time and temperature, final frying time and temperature on the oil uptake, texture, dry matter and colour of the fried yam slices has been studied. Frying conditions optimized with Box-Behnken experimental design were short pre-frying and frying conditions at high temperature characterized by pre-frying temperature at 157-170°C during 5-9s and frying temperature at 181-188°C for 2min 15s-2min 30s; or long pre-frying and frying conditions at low temperature characterized by pre-frying temperature at 150-158°C during 10-15s and frying temperature 170-177°C for 3-3min 15s. An adiabatic system was also developed by means of an insulator in which the core temperature of fried yam slices can be maintained constant at about 55°C after 15min of cooling, facilitating texture measurements at constant temperature. The present results may help in choosing the yam slices frying condition to be applied in order to achieve the desirable fried yam slices quality, required for protection against certain diseases like obesity. These models may also provide guidance as to how to control these quality parameters by altering four key environmental factors, pre-frying temperature and time and, final frying temperature and time. This process can also be commercialized and does not necessitate any other cost for equipment than those used for potatoes French fries and might be an interesting way of added value processing for this highly perishable yam tuber. [less ▲]

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See detailAbundance and phenological model of Harmonia axyridis (Coleoptera: Coccinellidae) in field crops
Vandereycken, Axel ULg; Brostaux, Yves ULg; Joie, Emilie ULg et al

Poster (2012, December 07)

The multicolored Asian ladybeetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) was introduced into Western Europe in the late 1990s. This exotic and invasive species is known to thrive ... [more ▼]

The multicolored Asian ladybeetle Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) was introduced into Western Europe in the late 1990s. This exotic and invasive species is known to thrive principally in shrubs and arboreal habitats. We focus on a phonological model and on annual abundance in various field crops. The abundance of H. axyridis adults and larvae were evaluated during a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. H. axyridis colonizes and reproduces in all four crops studied, with larger densities observed in corn and broad bean. The reproduction of H. axyridis occurs principally in corn and occurred much less in wheat and potato. From 2009 to 2011, abundances of H. axyridis populations were constant except in corn, where the observed densities of all immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis were characterized by a symmetric logistic function (S-shape) based on the cumulative population size. [less ▲]

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