Carbon nanotubes (CNTs) are nanometer-sized structures that can be used to reinforce cement matrices. The extent to which the mechanical properties are improved depends on the interfacial characteristics of the resulting materials, that is, on the interactions established between the CNTs and the cement. The experimental characterization of these interfaces is still impeded by technical limitations.
View Article and Find Full Text PDFLatent infections caused by spp. in nectarines cause great economic losses since they are not detected and rejected at harvest and can appear at any time post-harvest, even at the consumer's home. The effect of a pre-cooling chamber, water dump operation, and cold-storage chamber on the activation and/or development of preharvest latent infections caused by spp.
View Article and Find Full Text PDFThe use of genetically modified varieties tolerant to herbicides (HT varieties) and resistant to insects (Bt varieties) in combination with application of a broad-spectrum herbicide such as glyphosate could be an effective option for the simultaneous control of weeds and pests in maize. Nevertheless, the possible impact of these tools on nontarget arthropods still needs to be evaluated. In a field study in central Spain, potential changes in populations of canopy-dwelling arthropods in Bt maize under different weed management options, including glyphosate application, were investigated.
View Article and Find Full Text PDFPlanting flower strips adjacent to crops is among the habitat-management practices employed to offer alternative floral resources to pollinators. However, more information is needed to understand their potential spill-over of pollinators on nearby insect-pollinated crops. Over the course of two consecutive years, the suitability of a flower mixture of 10 herbaceous plants for pollinators was evaluated on a weekly basis, in a randomized block design of two melon plots (10 × 10 m) with or without 1 m-wide flower strips.
View Article and Find Full Text PDFInsecticide selectivity to natural enemies is an important concern in integrated pest management programs. Although there is a wide range of information concerning pesticide lethal and sublethal effects on contaminated surfaces, little is known when the route of exposure occurs at a trophic level. This study evaluates this route of pesticide intake on the omnivorous predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) for the first time.
View Article and Find Full Text PDFBackground: Monosteira unicostata is an important pest of almond tree in the Mediterranean region requiring control methods alternative to synthetic pesticides. The efficacy of kaolin, azadirachtin and potassium salts of fatty acids combined with thyme essential oil against adults and fourth instar nymphs of this tingid was evaluated in laboratory assays.
Results: In no choice assays with adults, kaolin significantly increased mortality compared to control (42.
The promoter sequences of the encoding genes for the three most abundant hexamerins of the Lepidoptera Trichoplusia ni were isolated and cloned into the Autographa californica multiple nucleopolyhedrovirus (AcMNPV)-derived baculovirus expression vector. From the sequences analyzed, the DNA region driving the expression of the Basic juvenile hormone-suppressible protein 2 (BJHSP-2), denominated pB2, presented the highest promoter strength in the context of the baculovirus vector in Sf21 insect cells. This promoter activity occurred earlier in baculovirus-infected cells than that achieved by a conventional polyhedrin promoter (polh), but surprisingly stopped at 48h post-infection.
View Article and Find Full Text PDFBackground: Insect growth regulators (IGRs) act specifically on arthropods. This selectivity makes them an interesting alternative to traditional insecticides for pest control. The aim of this work was to test the IGRs azadirachtin, cyromazine, flufenoxuron, lufenuron and pyriproxyfen as useful pesticides for the control of the olive fruit fly, Bactrocera oleae (Rossi), a key pest of olive crops.
View Article and Find Full Text PDFThe astigmatid mite Tyrophagus neiswanderi Johnston and Bruce is mainly considered a pest of ornamental and horticultural crops. However, this mite has been found infesting Cabrales cheese in Spain, though its population density is low compared to Acarus farris, the prevalent species of astigmatid mite encountered in Cabrales cheese maturing caves. One of the factors that might be influencing this differential abundance is temperature.
View Article and Find Full Text PDFLaboratory experiments were conducted to establish the best combination of relative humidity (r.h.) and time of exposure to be applied on Cabrales cheeses infested with Acarus farris.
View Article and Find Full Text PDFThe developmental rate of immature stages and the reproduction of adults of Tyrophagus putrescentiae (Schrank), T. neiswanderi Johnston and Bruce and Acarus farris (Oudemans) were examined at 70, 80 and 90% r.h.
View Article and Find Full Text PDFThe effect of temperature on reproductive parameters and longevity of the mold mite, Tyrophagus putrescentiae (Schrank) was examined at seven constant temperatures, ranging from 10 to 34 degrees C, and a relative humidity of 90 +/- 5%. Preoviposition period and fecundity were adversely affected by extreme temperatures and the oviposition period increased as temperature was reduced. Different patterns were observed for longevity data for males and females, with greater longevities for males at intermediate temperatures and more similar values for both sexes at extreme temperatures.
View Article and Find Full Text PDFThe storage mite, Tyrophagus putrescentiae (Schrank), is an important source of airborne allergens, especially on farms. Three insect growth regulators (halofenozide, pyriproxyfen, hexaflumuron), one botanical insecticide (azadirachtin) and one naturalyte (spinosad) were tested to assess their efficacy against this mite. The organophosphate chlorpyrifos was used as a standard.
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