Bestrijding van weekhuidmijten in gerbera

Nine species of Phytoseiidae were evaluated as predators of Tarsonemus violae (Schaarschmidt) and the broad mite Polyphagotarsonemus latus (Banks) on gerbera plants in experimental and commercial greenhouses. Amblyseius cucumeris, Amblyseius swirskii, Typhlodromips montdorensis and Amblyseius andersoni appeared to possess the best abilities to control tarsonemids in this crop. These species showed good survival and reduced mite densities at low levels directly after their releases. However, curative releases did not effectively eliminate tarsonemids and the predators could not keep pests density below economic damage threshold year round without further releases. The importance of repeated introductions of suitable predators at an early stage of infestation was demonstrated in the experiments. We recommend releases of A. swirskii, A. cucumeris and T. montdorensis

Geïntegreerde bestrijding van trips in roos: Evaluatie van nieuwe roofmijten

Abstract Predatory bugs (Anthocorids) and predatory mites (Phytoseiids) are the most effective beneficials against thrips. If predatory bugs have low affinity to the rose crop, there is a series of predatory mites which is suitable for this crop, including Amblyseius swirskii, Euseius ovalis, Typhlodromalus limonicus, Amblyseius degenerans, Amblyseius andersoni and Amblyseius aurescens. The low humidity in the leaf microclimate by prolonged periods of heat can be a limiting factor. Therefore, drought-resistant mites (‘desert species’) were selected in this study and tested for their affinity for thrips and roses. Euseius stipulatus and Typhlodromus exhilaratus were found to be drought-resistant species and to predate on thrips. Euseius stipulatus settled on roses. Due to a shortage of rearing, the affinity of Typhlodromus exhilaratus for roses was not tested

Biologische bestrijding van wittevlieg in de sierteelt

In de glastuinbouw vormen wittevliegen een oprukkend probleem. Naast de bekende kaswittevlieg, Trialeurodes vaporariorum, wordt ook tabakswittevlieg, Bemisia tabaci, steeds belangrijker. In de vruchtgroenteteelten wordt veel gebruik gemaakt van natuurlijke vijanden: de roofwants Macrolophus caliginosus en de sluipwespen Encarsia formosa en Eretmocerus eremicus. In de sierteelt stoelt de beheersing van deze plaag voornamelijk op het gebruik van insecticiden. In 2006 moesten zelfs geïntegreerde telers veelvuldig corrigeren met Admiral, Applaud, Actara, Calypso, Gazelle en Admire. Het Productschap Tuinbouw financiert in 2007 onderzoek bij Wageningen UR Glastuinbouw naar de biologische bestrijding van wittevlieg. Via internationale contacten en producenten van natuurlijke vijanden werden natuurlijke vijanden opgespoord. In insectendichte kassen van de nieuwe vestiging te Bleiswijk werd de interactie tussen de verzamelde natuurlijke vijanden en wittevlieg bestudeerd. Predatoren zijn getest op gerbera, roos en poinsettia zowel op afzonderlijke planten in kooien als in een gewas. Er werd gewerkt met “haardopruimers” en “onderhoudsagenten”. Onderzocht werd in hoeverre geselecteerde natuurlijke vijanden bestand zijn tegen moderne chemische middelen, en hoe zij zich handhaven bij korter wordende dag. Uiteindelijk werden bestrijdingsstrategieën getoetst bij drie telers

Pengaruh ketebalan terhadap proses Pengerolan panas baja HSLA API 5L-X65 Produksi Krakatau Steel

ABSTRACT The influence of thickness strip on the hot-rolling process was investigated The thickness of strip is one part of parameter on hot-rolling process since it gives different mechanical properties for different thicknesses. The toughness of thicker strip can be improved by lowering the temperature to the nonrecrystallization temperature. This should be in the range 950-900° C

Validation of Phonon Physics in the CDMS Detector Monte Carlo

The SuperCDMS collaboration is a dark matter search effort aimed at detecting the scattering of WIMP dark matter from nuclei in cryogenic germanium targets. The CDMS Detector Monte Carlo (CDMS-DMC) is a simulation tool aimed at achieving a deeper understanding of the performance of the SuperCDMS detectors and aiding the dark matter search analysis. We present results from validation of the phonon physics described in the CDMS-DMC and outline work towards utilizing it in future WIMP search analyses.Comment: 6 Pages, 5 Figures, Proceedings of Low Temperature Detectors 14 Conferenc

Inventarisatie van muggenlarven in de sierteelt onder glas

Verschillende soorten muggenlarven kunnen een plaag vormen in de sierteelt. Ze leven op of in de bodem en in rottende plantenresten. Daar voeden ze zich voornamelijk met dood organisch materiaal en de schimmels die daarop groeien. Sommige soorten doen schade door aan jonge wortels en zachte plantendelen te eten. In de sierteelt treden de laatste jaren problemen op met muggenlarven van het geslacht Lyprauta, die men in de wandelgangen “potworm” heeft gedoopt. Deze worden tot de familie van de langhoornmuggen gerekend. Hun larven veroorzaken problemen in met name potorchideeën, maar worden ook gemeld in Anthurium, gerbera en enkele groene potplanten

Characterization of flow rate and Heat Loss in Heating, Ventilation and Air Conditioning (HVAC) Duct System for Office Building

A building is an assemblage that is firmly attached to the ground and provides the performance of human activities and need to be considered in the daily operation in that building. The improvements in building performance are focused on improving the energy efficiency of buildings. This is approach by designing heating, ventilation and air conditioning (HVAC) duct system due to one of the most utilized energy in maintaining building performance and environment. The objectives of this research is to calculate the air (CFM) supply in office building, to characterize the velocity and head loss in a round and rectangular HVAC ducting system at various duct thickness and to optimize the thickness of the duct in HVAC system according to ASHRAE Standard. The increasing of velocity in duct system shows the increasing of head loss. The round duct design gives the lowest velocity and head loss in HVAC system approximately around 9.35% as compared to rectangular duct at 0.06 inches thickness. Hence, the trends of the head loss and duct thickness has influenced in reducing noise in HVAC duct system in order to select the best design concepts which is round shape design