436 research outputs found
Complementary studies to validate the proposed fumigation schedules of sulfuryl fluoride for inclusion in ISPM No. 15 for the eradication of Bursaphelenchus xylophilus from wood packing material
Plant-nematode co-cultures in the screening of sustainable nematicides against soil-dwelling parasitic nematodes of plants
The diseases caused by plant parasitic nematodes are still a serious constraint to modern global crop production. An
increasing number of active compounds in commercial nematicidal formulations is being banned from use by common
policies of pest management. Farmer communities report a low efficiency for the replacement pesticides, which reflects
on crop yield and productivity. Novel sustainable biopesticides are urgently needed to cope with global food demands
while respecting the most recent environmental policies. Plant-nematode co-cultures offer a stable biotechnological
screening tool able to assess the active compound’s nematicidal activity and its effect on host tissues, simultaneously,
in an easily accessible system that simulates natural infection. These systems are being developed and optimized at the
Nematology laboratory of INIAV. Preliminary results were obtained for co-cultures of Solanum lycopersicum with the
nematode Meloidogyne ethiopica and S. tuberosum with Globodera pallida. Future studies will target other plant parasitic
nematodes, e.g., the root lesion nematodes (Pratylenchus penetrans) in transgenic roots of potato and the pinewood
nematode (Bursaphelenchus xylophilus) on in vitro pine shoots (Pinus sp.)
Bioactivity of Monoterpene Alcohols as an Indicator of Biopesticidal Essential Oils against the Root Knot Nematode Meloidogyne ethiopica
The application of pesticides remains one of the most efficient control methods for phytophagous
parasites in crops. Essential oils (EOs) are complex mixtures of highly active compounds
that can be used as biopesticides against plant parasitic nematodes. In the present work, the antinematodal
activity of the monoterpene alcohols geraniol, linalool, menthol or -terpineol, which are
generally found in high amounts in EOs of some aromatic and medicinal plants, was analyzed on
the root knot nematode Meloidogyne ethiopica. Geraniol showed intense and lasting antinematodal
activity, suggesting that EOs rich in this compound can be used in the development of nematicidal
biopesticides to integrate sustainable pest management strategies against this pest
Evolution of qualitative and quantitative lipid profiles of high-pressure-processed serra da estrela cheese throughout storage
High-pressure processing (HPP) can be used as a nonthermal pasteurization technique to overcome microbial safety issues of the raw ewes’ milk Serra da Estrela cheese without negatively influencing its quality, in particular, the lipid composition partly responsible for Serra da Estrela cheese’s sensorial and textural attributes. The aim of this work was to assess HPP’s effect (600 MPa/6 min and 450 MPa/6 and 9 min) on the qualitative and quantitative lipid profiles of Serra da Estrela cheese during 15 months of refrigerated storage. Total triglycerides content (65–66 g TG/100 g) was similarly determined for HPP-treated (450 MPa/6 min) and control cheeses. Similar total contents of saturated, monounsaturated, and polyunsaturated fatty acids were reported for all cheeses during storage. A high total conjugated linoleic acid content (1.29–1.65 g FA/100 g fat) was quantified in all cheeses during storage; all cheeses revealed similar atherogenic and thrombogenic indices (~2.3 and ~2.6, respectively). HPP can be used to process Serra da Estrela cheese at conditions that assure microbial safety without influencing cheese lipid profiles.info:eu-repo/semantics/publishedVersio
Using biotechnology to solve engineering problems Non-destructive testing of microfabrication components
Fundacao para a Ciencia e a Tecnologia, I.P. (FCT), Portugal, for financial support under program "Investigador FCT 2013" (IF/01203/2013/CP1163/CT0002) and UID/BIO/04565/2013. TS and RM acknowledge FCT for PEst-OE/EME/UI0667/2014 and UID/EMS/00667/2013. The study was also partially supported by project PTDC/EME-TME/118678/2010.In an increasingly miniaturised technological world, non-destructive testing (NDT) methodologies able to detect defects at the micro scale are necessary to prevent failures. Although several existing methods allow the detection of defects at that scale, their application may be hindered by the small size of the samples to examine. In this study, the application of bacterial cells to help the detection of fissures, cracks, and voids on the surface of metals is proposed. The application of magnetic and electric fields after deposition of the cells ensured the distribution of the cells over the entire surfaces and helped the penetration of the cells inside the defects. The use of fluorophores to stain the cells allowed their visualisation and the identification of the defects. Furthermore, the size and zeta potential of the cells and their production of siderophores and biosurfactants could be influenced to detect smaller defects. Micro and nano surface defects made in aluminium, steel, and copper alloys could be readily identified by two Staphylococcus strains and Rhodococcus erythropolis cells.publishersversionpublishe
Performance assessment of polymer based electrodes for in vitro electrophysiological sensing: the role of the electrode impedance
Conducting polymer electrodes based on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) are used to record extracellular signals from autonomous cardiac contractile cells and glioma cell cultures. The performance of these conducting polymer electrodes is compared with Au electrodes. A small-signal impedance analysis shows that in the presence of an electrolyte, both Au and polymer electrodes establish high capacitive double-layers. However, the polymer/electrolyte interfacial resistance is 3 orders of magnitude lower than the resistance of the metal/electrolyte interface. The polymer low interfacial resistance minimizes the intrinsic thermal noise and increases the system sensitivity. However, when measurements are carried out in current mode a low interfacial resistance partially acts as a short circuit of the interfacial capacitance, this affects the signal shape
Insights into the role of fungi in Pine Wilt Disease
Pine wilt disease (PWD) is a complex disease that severely affects the biodiversity and
economy of Eurasian coniferous forests. Three factors are described as the main elements of the
disease: the pinewood nematode (PWN) Bursaphelenchus xylophilus, the insect‐vector Monochamus
spp., and the host tree, mainly Pinus spp. Nonetheless, other microbial interactors have also been
considered. The study of mycoflora in PWD dates back the late seventies. Culturomic studies have
revealed diverse fungal communities associated with all PWD key players, composed frequently of
saprophytic fungi (i.e., Aspergillus, Fusarium, Trichoderma) but also of necrotrophic pathogens
associated with bark beetles, such as ophiostomatoid or blue‐stain fungi. In particular, the
ophiostomatoid fungi often recovered from wilted pine trees or insect pupal chambers/tunnels, are
considered crucial for nematode multiplication and distribution in the host tree. Naturally occurring
mycoflora, reported as possible biocontrol agents of the nematode, are also discussed in this review.
This review discloses the contrasting effects of fungal communities in PWD and highlights
promising fungal species as sources of PWD biocontrol in the framework of sustainable pest
management actions
Diagnóstico de Cryptosporidium spp. por meio de nested-PCR em caprinos jovens de Quixadá, Ceará.
First report of Mesocriconema xenoplax (Nematoda: Criconematidae) from turfgrass in Portugal and in Europe
Venom-related transcripts from Bothrops jararaca tissues provide novel molecular insights into the production and evolution of snake venom.
Attempts to reconstruct the evolutionary history of snake toxins in the context of their co-option to the venom gland rarely account for nonvenom snake genes that are paralogous to toxins, and which therefore represent important connectors to ancestral genes. In order to reevaluate this process, we conducted a comparative transcriptomic survey on body tissues from a venomous snake. A nonredundant set of 33,000 unigenes (assembled transcripts of reference genes) was independently assembled from six organs of the medically important viperid snake Bothrops jararaca, providing a reference list of 82 full-length toxins from the venom gland and specific products from other tissues, such as pancreatic digestive enzymes. Unigenes were then screened for nontoxin transcripts paralogous to toxins revealing 1) low level coexpression of approximately 20% of toxin genes (e.g., bradykinin-potentiating peptide, C-type lectin, snake venom metalloproteinase, snake venom nerve growth factor) in body tissues, 2) the identity of the closest paralogs to toxin genes in eight classes of toxins, 3) the location and level of paralog expression, indicating that, in general, co-expression occurs in a higher number of tissues and at lower levels than observed for toxin genes, and 4) strong evidence of a toxin gene reverting back to selective expression in a body tissue. In addition, our differential gene expression analyses identify specific cellular processes that make the venom gland a highly specialized secretory tissue. Our results demonstrate that the evolution and production of venom in snakes is a complex process that can only be understood in the context of comparative data from other snake tissues, including the identification of genes paralogous to venom toxins
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