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41.
Soil chemical and biochemical properties of a salt-marsh alluvial Spanish area after long-term reclamation 总被引:2,自引:0,他引:2
Vito Armando Laudicina Maria Dolores Hurtado Luigi Badalucco Antonio Delgado Eristanna Palazzolo Michele Panno 《Biology and Fertility of Soils》2009,45(7):691-700
Marisma, one of the largest salt-marsh alluvial areas in SW Spain, has been reclaimed since 1970 by artificial drainage and
amendment with phosphogypsum (PG) so as to reduce Na+ saturation. Within the reclaimed area, two 250- × 20-m plots were treated as follows: (1) amendment with 25 Mg/ha of PG every
2 to 3 years between 1979 and 2003 (plot PY); (2) like PY but PG treatment stopped after 1997 (plot DR). A contiguous virgin
Marisma salt-marsh plot (MV), neither drained nor amended, was the control. In MV, soil microbial biomass C, most enzyme activities
and total organic C content were much greater than in PY and DR soils, despite the salinity stress. The decrease in soil organic
matter content in PY and DR soils was likely due to cotton-cropping practices, which favoured the organic C mineralisation
and nutrients removal by crops. Microbial activity of MV soil, probably stimulated by the rhizodepositions of the natural
vegetation, did not suffer from the osmotic effect due to the raising of soil solution ionic strength. Microbial quotient
could be ranked as MV > PY > DR, whereas the metabolic quotient had an opposite trend. Thus, both quotients suggested that
the interruption of PG amendment was not favouring microbial activity. Principal component analysis clearly identified the
chemical and biochemical soil properties mostly affected by the reclamation and also indicated the longer PG amendment in
PY plot. Stepwise discriminant analysis identified two physiologically different types of soil microflora, one less active
present in the MV virgin soil and another more active present in the reclaimed PY and DR soils. 相似文献
42.
Roberto A. Santilli Med Vet Luigi V. Bontempi Med Vet Manuela Perego Med Vet Lara Fornai Med Vet Cristina Basso MD PhD 《Journal of Veterinary Cardiology》2009,11(1):47-51
A 5-year-old English Bulldog was presented for acute onset of syncope and fatigue caused by sustained ventricular tachycardia with left bundle block morphology and inferior axis. This arrhythmia had the electrocardiographic features of a ventricular tachycardia arising from the right ventricular outflow tract (RVOT), as described in an experimental canine model and in people. Since a RVOT aneurysm was identified by echocardiography, a segmental form of arrhythmogenic right ventricular cardiomyopathy (ARVC) was suspected. Gross examination of the heart confirmed the bulging of the RVOT and histological examination of the ventricular myocardium revealed segmental involvement of the RVOT with transmural fibro-fatty degeneration. To the authors' knowledge, this is the first reported case of AVRC in an English Bulldog and the first example of segmental AVRC described in the dog. 相似文献
43.
Riccardo Aversano Salvatore Savarese Jose Maria De Nova Luigi Frusciante Maria Punzo Domenico Carputo 《Euphytica》2009,165(2):353-361
In this work we detected the extent of variability at nuclear and cytoplasmic DNA level of regenerated plants belonging to
Solanum genotypes with a different genetic background and somatic chromosome number. As for the nuclear characterization, a total
of 66 (18.5%) polymorphic bands were scored using 13 ISSR primers on 45 randomly selected regenerants. Our results show that
the regenerants obtained from clone cmm 1T and, at lower level, those from cph 1C are unstable under in vitro conditions or
rather more prone to in vitro-induced stress leading to somaclonal variation than the other genotypes used. Two types of changes
were observed: disappearance of parental ISSR fragments, termed “loss”; appearance of novel ISSR fragments, termed “gain”.
The most frequent event occurring in the regenerants was the loss of fragments (41 bands). Regenerated plants were analyzed
with seven plastid universal primers to determine the cytoplasmic composition at chloroplast level. All cpDNA primer pairs
tested produced amplicons of the same size in all genotypes analyzed and no polymorphic fragments were observed with any universal
primers used. Our results show that under in vitro culture conditions genotype affects the integrity of the genome. In addition,
the absence of polymorphism at plastid level confirms the greater genetic stability of cytoplasmic DNA. 相似文献
44.
Positive PCR alone should not be considered sufficient to establish Dirofilaria repens as the cause of subcutaneous nodular lesions in the absence of a clear cytologic picture
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45.
Alfredo Di Filippo Alfredo Alessandrini Franco Biondi Silvia Blasi Luigi Portoghesi Gianluca Piovesan 《Annals of Forest Science》2010,67(7):706-706
– |
• We combined stem volume increment analysis with dendroecological tools to address two unresolved issues concerning oak dieback
in Mediterranean areas: early detection of changes in stand growth, and identification of mechanisms for observed growth declines. 相似文献
46.
Gianluca Neglia Bianca Gasparrini Domenico Vecchio Marcello Rubessa Rossella Di Palo Luigi Zicarelli Giuseppe Campanile 《Tropical animal health and production》2010,42(6):1243-1247
The aim of this study was to evaluate the effect of exogenous progesterone supplementation on superovulatory response in buffaloes
that has undergone a multiple ovulation program. Fourteen Mediterranean buffaloes were divided into two groups and received
a 4-day decreasing dosage of an equal mixture of 500 IU of FSH and LH starting on day 8 of the cycle. In group A (n = 7) a progesterone-releasing intravaginal device was removed on day 8, whereas in group B (n = 7) it was left till day 10, when PGF2a {\hbox{PG}}{{\hbox{F}}_{{2}\alpha }} was administered. Eighty hours later, buffaloes were artificially inseminated and after 6 days they undergone uterine flushing.
A higher (P < 0.05) number of corpora lutea (8.3 vs. 5.7) and embryo/flushing/buffalo (2.3 vs. 1.3) were recorded in group B vs. group
A if responsive buffaloes are considered (n = 12) and the number of corpora lutea was highly correlated with the number of embryos (r = 0.65; P < 0.05). In conclusion, progesterone supplementation during the first 2 days of the superovulation treatment seems to enhance
the recovery rate in buffalo species. A high ovulation rate, associated with a high number of corpora lutea, can represent
a parameter for estimating embryo recovery. 相似文献
47.
Thibaut Olivier Vaidevutis Šveikauskas Elisabeth Demonty Kris De Jonghe Pascal Gentit Mojca Viršček-Marn Sabine Grausgruber-Gröger Sébastien Morio Francesco Faggioli Michèle Visage Frédéric Fauche Maria Gusina Marta Luigi Helena Lasner Irena Mavrič-Pleško 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(3):645-654
48.
Renzo Torricelli Donato Domenico Silveri Nicoletta Ferradini Gianfranco Venora Fabio Veronesi Luigi Russi 《Genetic Resources and Crop Evolution》2012,59(2):261-276
In the world lentil is grown on more than 3 million hectares and is one of the most important, low-cost, food source of protein.
In Italy lentil has been cultivated since ancient times, but in the last decades its cultivation has been confined to marginal
areas, small islands and hilly, mountainous areas of central and southern Italy. Local varieties are still common and are
often greatly appreciated for their taste and cooking qualities. Several accessions from the Santo Stefano di Sessanio area,
Abruzzo Region, were collected and phenotypically and genotypically characterized in order to look for the existing variability
within and between populations. Image analysis of seeds was also used. Populations grown in Santo Stefano di Sessanio and
in the neighbouring area basically share most of their characteristics. However, some of the accessions anonymously gathered
from the local market were shown to be different from those collected from farmers. The paper reports and discusses how this
local product needs be characterized and promoted in order to avoid fraud that could negatively affect the local economy and
put valuable, adapted, genetic resources at risk of erosion. 相似文献
49.
Gianluca Bianchini Claudio Natali Dario Di Giuseppe Luigi Beccaluva 《Journal of Soils and Sediments》2012,12(7):1145-1153
PurposeThis contribution investigates agricultural soils and sedimentary deposits in the province of Ferrara (Padanian alluvial plain, Northern Italy) in order to: examine their genesis; to define the geochemical background of the area; and to evaluate the existence of anthropogenic contamination. Moreover, environmental risk related to the presence of potentially toxic heavy metals that can be transferred into agricultural products (and consequently bio-accumulated in the food chain) was also assessed.Materials and methodsThe analyses (reported in an extensive supplementary dataset) include XRD, XRF and ICP-MS assessment of bulk sediments, tests of metal extraction with aqua regia, as well as analyses of local agricultural products, i.e. biomonitoring which is important in the evaluation of element mobility.Results and discussionBased on the results, GIS-based geochemical maps were produced and local background levels were defined. This approach demonstrated that high concentrations of Cr and Ni is a natural (geogenic) feature of the local alluvial terrains, which in turn is related to the origin and provenance of the sediments, as confirmed by the lack of top enrichment in all of the investigated sites. Tests of metal extraction and analyses of agricultural products provide guidelines for agricultural activities, suggesting that extensive use of sewage sludge, industrial slurry and manure (that are often rich in metals) should be minimised.ConclusionsThe dataset reported in this paper shows that the agricultural terrains of the studied alluvial plain are not characterised by anthropogenic heavy metal pollution. In spite of the elevated natural background of Cr and Ni, most of the local agricultural products do not show significant evidence of bio-magnification. Exceptions are represented by forage grass (alfalfa) and corn (maize) that tend to uptake As and Ni, respectively. This demonstrates that in agricultural areas, a geochemical risk assessment must include both soil and plant investigations. 相似文献50.
Costagliola A Britti D Russo V Meomartino L Castagna F Giordano D Insabato L Paciello O 《Avian diseases》2011,55(1):147-150
A common seagull (Larus fuscus) was found near the southern coast of Italy by the veterinarians of the local wild animal rescue center. Physical examination of the bird revealed an ulcerated mass involving a majority of the oral cavity; the mass did not allow for normal feeding. After the bird died necropsy was performed and the mass was histologically and immunohistochemically examined. The morphology and the immunoreactivity for Melan-A and S-100 antigens led to a diagnosis of malignant melanoma. This is the first case of malignant melanoma described in a seagull, and herein we compare the characteristics of the present case with malignant melanoma already described in domestic animals. 相似文献
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