8 research outputs found
Detailed morphobiometric studies of Bursaphelenchus xylophilus and characterisation of other Bursaphelenchus species (Nematoda: Parasitaphelenchidae) associated with Pinus pinaster in Portugal
Detailed studies on Bursaphelenchus xylophilus are provided in this contribution. Comparative observations
between field and cultured populations of this species demonstrated significant size differences: cultured specimens
overall displayed larger size in all morphometric parameters. A principal component analysis (PCA) of the individuals
undergoing moulting allowed their separation in four groups namely J2-J3, J3-J4, J4F-F, and J4M-M; gonad length mean values
of these four groups made possible to distinguish the non-moulting groups J2, J3, J4F, J4M and adults. Seven Bursaphelenchus
species (B. hellenicus, B. leoni, B. pinasteri, B. sexdentati, B. teratospicularis, B. tusciae and B. xylophilus), associated with Pinus
pinaster in Portugal, were charaterized, including biometrical measurements and ratios as well excised spicules observed
under SEM; furthermore, B. hellenicus, B. pinasteri, B. sexdentati, B. tusciae and B. xylophilus were characterised on the
basis of their ITS-RFLP profiles. B. sexdentati and B. xylophilus were the only species found in high numbers in some of
the samples
Species of Bursaphelenchus Fuchs, 1937 (Nematoda: Parasitaphelenchidae) associated with maritime pine in Portugal
Summary – Species of Bursaphelenchus associated with maritime pine, Pinus pinaster, from Portugal – within and outside the
quarantine restricted demarcated zone of B. xylophilus – are described and characterised both morphologically (LM and SEM) and with
the use of molecular biology (ITS-RFLP).A new staining method for spicules is proposed. Species include B. hellenicus, B. hylobianum,
B. leoni, B. pinophilus, B. sexdentati, B. tusciae, B. teratospicularis, B. xylophilus and Bursaphelenchus sp. 1. Bursaphelenchus
hylobianum was collected from the insect Hylobius sp. The most frequent species in the demarcated zone, besides B. xylophilus, was
Bursaphelenchus sp. 1. Morphological characterisation is compared with the original descriptions and discussed. The differentiation
between B. pinophilus and B. sexdentati is not clear in the literature and is discussed. Since differentiation of B. xylophilus (mucronate
form) from B. mucronatus, and B. pinophilus from B. sexdentati, as well as their juvenile forms, is almost im possible on the basis
of morphological features, a molecular approach based on ITS-RFLPs was used. Ribosomal DNA containing the 5.8S gene, the
internal transcribed spacer region 1 and 2, and partial regions of 18S and 28S gene were amplified by PCR. Restriction profiles
of the amplified products generated species-specific differences, leading to the unambiguous identification of isolates belonging to
B. xylophilus, B. mucronatus, B. sexdentati, B. tusciae and B. hylobianum
RNA interference in Lepidoptera: an overview of successful and unsuccessful studies and implications for experimental design
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RNA interference in Lepidoptera: An overview of successful and unsuccessful studies and implications for experimental design
Bursaphelenchus xylophilus (Nematoda; Aphelenchoididae) associated with Monochamus galloprovincialis (Coleoptera; Cerambycidae) in Portugal
Early meteorological records from Extremadura region, SW Iberia (CliPastExtrem)
Meteorological observations made in the region of Extremadura (SW Iberia) from 1826 to mid-20th century have been retrieved. Variables such as air temperature, atmospheric pressure, precipitation, wind direction and humidity, among other, were recorded in these observations. In total, more than 700000 instrumental data were digitized (79.8 % with daily resolution)
Characterisation of microbial attack on archaeological bone
As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved