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Mealybugs (Hemiptera: Pseudococcidae) are sap-sucking insects which infest a broad range of crops worldwide. They represent
an important threat to viticulture as they are vectors of viruses associated with leafroll and rugose wood complex diseases.
In this study, we surveyed the presence of mealybugs and their associated viruses in vineyards of the Piemonte and Liguria
regions, northwestern Italy. In order to determine the collected specimens correctly, we added a species-specific marker for
Heliococcus bohemicus to an existing molecular identification key. The only species collected in Piemonte was H. bohemicus, whereas in Liguria, H. bohemicus, Planococcus ficus and Pseudococcus longispinus were found; Ps. longispinus has never before been reported in Italian vineyards. Several specimens of all three species were infected by the ampeloviruses
GLRaV-1 and GLRaV-3 and the vitivirus GVA. Both nymphs and adult females tested positive for the viruses and mixed infections
were commonly found within the same insect. Population levels and virus incidence were higher in Liguria than in Piemonte,
suggesting a greater risk of disease spread. We conclude that the mild, Mediterranean climate of Liguria favors the development
of a diverse mealybug fauna while only H. bohemicus, known to be tolerant to the severe continental winter temperatures, colonize grapevines in colder viticultural areas. 相似文献
104.
Silvia Preziuso Fulvio Laus Aurora Romero Tejeda Carlo Valente Vincenzo Cuteri 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(1):67-72
Streptococcus (S.) dysgalactiae subsp. equisimilis is responsible for severe diseases in humans, including primary bacteraemia, pneumonia, endocarditis, and toxic shock syndrome. Infection in some animal species can also occur, although a few studies have looked into cross-species infectivity. In horses, S. equisimilis is generally considered infrequent or opportunistic, but has recently been isolated from cases of strangles-like disease. Rapid and sensitive diagnostic techniques could enable epidemiological studies and effective investigation of outbreaks involving these bacteria. In this study, PCR protocols previously described in cattle and in humans to detect the species S. dysgalactiae and the subspecies equisimilis were evaluated to detect specific sequences in equine samples. For this purpose, 99 monolateral nasal swabs were collected from horses from stud farms with a history of S. equisimilis infection and were tested blindly by bacteriological isolation and by single and duplex PCR. DNA for PCR was extracted both from the colonies grown on agar media and from enrichment broth aliquots after incubation with nasal swab samples. S. equisimilis was identified by bacteriological isolation in 23 out of 99 swab samples, and PCR assays on these colonies were fully concordant with bacteriological identification (kappa statistic = 1.00). In addition, PCR of the enrichment broth aliquots confirmed the bacteriological results and detected S. equisimilis in 6 samples more than the bacteriological examination (kappa statistic = 0.84). The PCR protocols appeared to be reliable for the rapid identification of S. equisimilis in equine nasal swab samples, and could be useful for microbiological diagnosis. 相似文献
105.
ABSTRACT The effect of different combinations of temperatures and exposure times on the mortality of Heterodera schachtii eggs was assessed in two different experiments under laboratory conditions. In the first experiment, cysts in water were exposed to 25, 35, 37.5, 40, 42.5, 45, 47.5, 50, or 52.5 degrees C for a maximum period of 2 h. In the second experiment, cysts in naturally infested soil were exposed to 25, 32.5, 35, 37.5, 40, 42.5, or 45 degrees C for a minimum period of 2 h to a maximum of 2,048 h. Viability of eggs in cysts was assessed by a hatching test in 3 mM zinc chloride solution. Viability in water was suppressed after 2-h exposure at 50 degrees C and inhibited after 1 to 2 h at 52.5 degrees C. Emergence of juveniles from cysts in soil was greater at the lower temperature x exposure time combinations and suppressed at higher combinations. Egg mortality started after exposure for 256 h at 40 degrees C, 32 h at 42.5 degrees C, and 16 h at 45 degrees C, and 81, 31, and 7 h of exposure were necessary to kill 50% of the nematode egg population at 40, 42.5, and 45 degrees C, respectively. The data fitted the models P(t) = P(0)10(-t/ (q + mT)) and P(T1) = P(T0)10(-T/(z - pt)) for m = -0.0111, q = 0.8238, z = 2.444, and p = -0.23. 相似文献
106.
The aim of this work is to study three soil solarizing film's (EVA, COE and BIO) effects on microbial biomass and their respiration activities and beside on some agronomic traits of tomato and melon as subsequent vegetable crop cultivation on solarized soil. The responses are that the used films increased different temperature levels in the soil; in fact, in the upper soil depth, BIO film, during the 37 days of solarization treatments, reached 137 h in which the recorded temperatures went over 60 °C, followed by EVA film with 80 h and COE film with 60 h affecting variously the thermic regime. The used films had great effects on all microbiological (MBC and MBN) and enzymatic parameters (alkaline phosphatase, acid phosphatase, β-glucosidase and arilsulphatase). Furthermore, the variation of root-knot nematodes (Meloidogyne javanica) on tomato and melon roots were assessed and some qualitative and yield traits of both vegetable crops were also reported as affected by soil solarization treatments. In all cases the BIO film has showed comparable yield results with EVA and COE films, with the advantage that it is compatible for a more sustainable agriculture practice. 相似文献
107.
Napolitano A Cascone A Graziani G Ferracane R Scalfi L Di Vaio C Ritieni A Fogliano V 《Journal of agricultural and food chemistry》2004,52(21):6526-6531
Apple is among the most consumed fruits worldwide. It is available on the market for the whole year being a major source of dietary polyphenols. Several studies suggested that apple polyphenols could play a role in prevention of degenarative diseases. The action of these compounds has been partially ascribed to their antioxidative ability, and fruit antioxidants profile is influenced by apple variety and by the postharvest storage. In this work, the polyphenols composition of the flesh of four apple varieties cultivated in southern Italy were investigated by HPLC, and a flow injection MS/MS procedure to quantify cholorogenic acid and catechins was set up. Phenolic composition and the radical scavenging activity were monitored during a postharvest storage of four months. The quantification by flow injection procedure gives results comparable to those obtained by HPLC, and the increase of the antioxidant activity during storage correlated with an increase of the concentration of catechin and phloridzin. This trend is particularly evident for the variety "Annurca" which is a typical product cultivated in the area around Naples. The genetic characteristics of the Annurca variety together with the anticipated harvest time and the peculiar postharvest conditions are likely responsible for this increase of the antioxidant activity. 相似文献
108.
Giulia Capotorti Domenico Guida Vincenzo Siervo Daniela Smiraglia Carlo Blasi 《Biological conservation》2012,147(1):174-183
The aims of this study are to describe the ecological classification of land in Italy and to show how the resulting land units can act as reliable frameworks for coarse scale environmental analyses that can be used to implement national conservation strategies. We first collected, homogenised and drew physical thematic maps, which were then linked to biological and human features. We then performed a gap analysis of land heterogeneity compared with Natural Protected Areas and Natura2000 network on the basis of three categories: Total gaps, Partial gaps, and Protected. Moreover, we assessed the conservation status of the land units by summarising the environmental quality using the Index of Landscape Conservation. We identified and mapped 3 Land Regions, 24 Land Systems, and 149 Land Facets. Total gaps account for 28% of the country, Partial gaps for 38% and Protected for 34%. The Natura2000 network is more representative than the system of National Protected Areas of the overall land heterogeneity as regards both the types (18 out of 24) and extent (72%) of the Land Systems. Low conservation status prevails in the Land Facets of the Mediterranean Region located along the coasts and plains on sedimentary deposits, whereas high and very high conservation status is found along the higher belts of the Alpine and Apennine chains. These results highlight the potential use of ecological land classification for biodiversity monitoring and conservation purposes, e.g. when identifying land units that need to be recovered or targeted for enhanced biodiversity and ecosystem services protection. 相似文献
109.
110.
Francesco Giuffrida Giulia Graziani Vincenzo Fogliano Domenica Scuderi Daniela Romano Cherubino Leonardi 《Journal of plant nutrition》2014,37(9):1455-1474
The effects of nutrient or sodium chloride (NaCl) salinity on pepper grown in closed soilless culture systems were studied. A control (2 dS m?1) and two saline nutrient solutions (4 dS m?1) differing in the salt sources (fertilizers or NaCl) were studied. Shoot biomass production as well as total and marketable yield were more affected by NaCl than nutrient salinity. Fruit dry matter and total soluble solids increased in both salinity treatments compared to the control. Total phenol content rose slightly (10%) with NaCl salinity, while the concentration of carotenoids was enhanced by 40% with NaCl compared to the control and nutrient salinity. The results showed that the response of pepper to salinity is both osmotic and ion specific, but a more negative effect was recorded under NaCl stress. Moreover, the highest content of antioxidant compounds in NaCl treated fruits may indicate that NaCl caused more stressful conditions than nutrient salinity. 相似文献