Coffee berry borer Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae) removal in coffee plantations: a pest control service provided by birds

Coffee is one of the most important crops in tropical regions of the world, where areas suited for its production are usually immersed within important biodiversity conservation regions. Studies in these agricultural systems have proven its conservation value, particularly for bird species which provide us with an array of ecosystem services including seed dispersal, pollination, and pest control. Regulating ecosystem services such as pest control (MEA 2005) are especially important to quantify because their benefits can be perceived at smaller scales and directly by coffee growers. Positive effects of bird species in the removal of insects in coffee systems have already been established however fewer studies have focused specifically on the effect of bird species in the control of the coffee berry borer (cbb), one of the most damaging pests affecting coffee production worldwide. In order to assess this effect on January 2013 we set up an exclosure experiment in a Costa Rican coffee plantation where we randomly selected two coffee shrubs at ten different coffee plots, one of the coffee shrubs was then isolated from bird foraging activity by a plastic mesh preventing the entrance of birds but allowing insects to fly in and out. Brocap traps were installed at each one of the ten coffee plots to monitored cbb flights/availability, bird community was evaluated via point counts and mistnetting and direct evidence of predation was obtained through the identification of cbb DNA in fecal and emesis samples. Results show that 25% out of 117 bird species detected within our sampling units are exclusively insectivorous birds while 55% include invertebrates as part of their diet. Trapping of cbb indicated several episodes of flights/availability of the pest throughout the year. Coffee berry borer infestation rates were significantly higher in coffee shrubs excluded in comparison with coffee shrubs exposed to bird foraging activity (F=23.40, p=0.0019). Preliminary DNA analysis shows evidence of insectivorous bird species predating on the genus Hypothenemus. Our findings provide further evidence on the potential contribution of insectivorous bird species in the removal and control of the coffee berry borer in coffee systems and highlight the importance of further studies using molecular biology techniques that allow to quantify the amount of cbb consumed by birds on a given moment as well as the economic importance of this service. (Texte intégral

Kombilohn: die Frage ist nicht 'ob', sondern 'wie'

Die Diskussion um den Kombilohn wurde kürzlich durch eine Initiative der CDU/CSU-Fraktion neu belebt. Der Vorschlag, Arbeitslosenhilfe und eigenes Einkommen zu kombinieren, stieß allerdings auf vielfältige Kritik. Welche Gründe sprechen dennoch für einen Kombilohn? Wie sollte die Lohnsubventioriierung ausgestaltet werden? --

Kombilohn: die Frage ist nicht 'ob', sondern 'wie'

Die Diskussion um den Kombilohn wurde kürzlich durch eine Initiative der CDU/CSU-Fraktion neu belebt. Der Vorschlag, Arbeitslosenhilfe und eigenes Einkommen zu kombinieren, stieß allerdings auf vielfältige Kritik. Welche Gründe sprechen dennoch für einen Kombilohn? Wie sollte die Lohnsubventioriierung ausgestaltet werden

Whey protein hydrolysis with free and immobilized Alcalase®: effects of operating parameters on the modulation of peptide profiles obtained

In this work, the effects of operating parameters on the modulation of peptide profiles obtained during enzymatic hydrolysis of whey protein concentrates (WPC) with a commercial enzyme (Alcalase 2.4L AF) were analyzed. Hydrolyzates of WPC were obtained working with free and immobilized enzyme and evaluating different operating conditions (initial substrate concentrations, time, temperature and pH). Characteristics of hydrolyzates obtained were evaluated by the hydrolysis degree obtained (DH) and the peptide profile by RP-HPLC. Moreover, a quantitative descriptive sensory analysis was performed to compare different preparations of commercial desserts prepared using as ingredients milk, WPC and WPC hydrolyzates. The DH values increased very quickly during the first 10 min. followed by a slow increase up to 25 min. For the range of conditions tested, we proposed to operate at temperatures close to 50˚C, pH between 8 and 9 and initial substrate concentration from 7% as good reactions conditions. Finally, whey protein hydrolyzates obtained with Alcalase showed very interesting sensorial characteristics to be incorporated in desserts commercial preparations.Fil: Fenoglio, Cecilia Lorena. Universidad Nacional del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vierling, Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Manzo, Ricardo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Ceruti, Roberto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Sihufe, Guillermo Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; ArgentinaFil: Mammarella, Enrique José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Desarrollo Tecnológico para la Industria Química. Universidad Nacional del Litoral. Instituto de Desarrollo Tecnológico para la Industria Química; Argentin