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81.
The braconid parasitoid Psyttalia concolor foraging for larvae of Bactrocera oleae (Diptera: Tephritidae) uses olfactory cues from the larval microhabitat. However, it could rely on the sex pheromones of adults of its host, since B. oleae mating leks usually occur on olive plants and a high number of infested fruits can be easily located in their close proximity. We quantified the behavioural responses of P. concolor towards different doses of the two major sex pheromone components of B. oleae, the female-borne 1,7-dioxaspiro[5.5]undecane (DSU) and the male-borne (Z)-9-tricosene (ZT). Results showed that P. concolor females and males were attracted only to the highest amounts of ZT (10 B. oleae male equivalents), regardless of the mating status. Wasps remained longer on the surfaces treated with high ZT amounts over the control. P. concolor females could exploit the ZT produced by lekking olive fruit fly males as a foraging kairomone. This could allow them to rapidly track B. oleae-infested olive plants, thus raising their chances to locate host larvae during their lifespan. On the other hand, the perception of ZT by P. concolor males could raise their chances to locate receptive females emerging from parasitised B. oleae pupae or also ovipositing in olive fruits. This study increases the knowledge of the reproductive biology of P. concolor, highlighting a case of chemical espionage in which a sex pheromone component from adult stages of the host is exploited both as a foraging kairomone by female parasitoids and as a sexual kairomone by male wasps.  相似文献   
82.
Seventy-four dogs from the State of Rio de Janeiro with ulcerated cutaneous lesions were submitted to clinical, dermatological, parasitological, mycological, histopathological and cytopathological exams, a leishmanin skin test, an indirect immunofluorescence (IIF) test for leishmaniosis, and nonspecific laboratory tests such as blood count and serum biochemistry. Sporothrix schenckii was isolated from 41 dogs and Leishmania (Viannia) braziliensis was isolated from 33 animals. Most dogs with sporotrichosis were from the municipality of Rio de Janeiro (53.7%) and presented ulcerated cutaneous lesions on the head (68.3%). Laboratory alterations in these animals included anemia (58.5%), hypoalbuminemia (83%) and hyperglobulinemia (75.6%). Histopathology revealed the predominance of a chronic granulomatous inflammatory infiltrate (70.7%), and yeast-like structures were detected in 17% of the histopathological exams and in 32% of the cytological exams. Three of 41 dogs with sporotrichosis were seropositive by IIF for leishmaniosis and 2 of 20 animals tested within this group had a positive leishmanin skin test. Similarly, most of the 33 dogs with leishmaniosis were from the municipality of Rio de Janeiro (69.7%) and had ulcerated cutaneous lesions on the head (84.8%). Laboratory alterations in these animals included anemia (66.7%), hypoalbuminemia (100%) and hyperglobulinemia (91%). Histopathology showed the predominance of a chronic granulomatous inflammatory infiltrate (63.6%) and amastigote forms were detected in 30.3% of the histopathological exams and in 31.8% of the 22 cytological exams performed. About 72.7% of the dogs were seropositive by IIF and five of seven animals had a positive skin test. Due to the clinical similarities, histopathological and nonspecific laboratory results similarities, the serological and skin tests for leishmaniosis positive in dogs with sporotrichosis, and the overlapping endemic areas in Rio de Janeiro, the differential diagnosis between the two diseases requires the demonstration of their respective etiological agents.  相似文献   
83.
The chemical composition of the Sardinian botargo by Mugil cephalus from different geographical origins was investigated. Fat ( approximately 20%), proteins ( approximately 50%), moisture ( approximately 22%), and salt ( approximately 7%) were measured in ground (G) and whole (W) commercial products. Among the nutritional compounds, omega-3 fatty acids were approximately 8%, squalene was approximately 15 mg/100 g, vitamin E was approximately 8.5 mg/kg, and cholesterol was approximately 300 mg/100 g, on average in both products. Antioxidant properties, assessed by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) test and expressed as Trolox equivalent antioxidant capacity (TEAC), showed quite good activity in extracted oil (0.8-1.1 mmol of Tolox/L). Major constituents in the samples varied noticeably, but only few statistical differences were evidenced between G or W products or between samples from different origins. Principal component analysis (PCA) of random amplified polymorphic DNA (RAPD) and proteins, coupled with both, did not differentiate samples from different origins. On the basis of our results, chemical and molecular data exclude the differentiation of samples from diverse origins.  相似文献   
84.
Small‐scale driftnets (SSDs) have been historically used in the Mediterranean without major environmental concern. The introduction of large‐scale driftnets caused unwanted catches of protected species. Specific regulations were therefore issued in European waters, culminating in a proposed moratorium on SSDs. This study aimed to characterise the SSD fishery targeting anchovy (menaide), evaluating its environmental sustainability, economic performance and social relevance. In 2013, a survey by interviews, logbooks and observers on board assessed the order of magnitude of this fishery in terms of fishing capacity and activity, volume of landings and revenues. The menaide fleet consisted in 60 vessels <12 m overall length, moored in little harbours in southern Italy. These nets are highly selective: the target species, European anchovy, Engraulis encrasicholus (L.) and sardine, Sardina pilchardus (Walbaum), dominates the catches, while discards are negligible. The anchovies caught are of high quality and large size; the high prices support fish processing by local factories. Moreover, the results of a SWOT analysis demonstrated that replacing SSDs with a semi‐industrial fishery, like purse seining, would increase impacts on the ecosystem, and a loss of socio‐economic opportunities for several coastal villages. These findings support the option of keeping SSDs operating, in the framework of specifically oriented management measures.  相似文献   
85.
Quince (Cydonia oblonga Miller) fruit aqueous acetone extracts were evaluated. High-performance liquid chromatography-diode array detection and electrospray ionization-mass spectrometry were used for the identification and quantification of the phenolic compounds. The total phenolic content of the pulp and peel parts ranged from 37 to 47 and 105 to 157 mg/100 g of fresh weight, respectively. Chlorogenic acid (5-O-caffeoylquinic acid) was the most abundant phenolic compound in the pulp (37%), whereas rutin (quercetin 3-O-rutinoside) was the main one in the peel (36%). The radical scavenging potential of the extracts was determined and compared with that of synthetic antioxidants. The stronger properties corresponded to those obtained from peel material with a 70-80% inhibitory effect on DPPH radicals. The antimicrobial activity of the extracts against different microorganism strains was also investigated. Quince peel extract was the most active for inhibiting bacteria growth with minimum inhibitory and bactericide concentrations in the range of 102-5 x 103 microg polyphenol/mL. It seems that chlorogenic acid acts in synergism with other components of the extracts to exhibit their total antimicrobial activities.  相似文献   
86.
In southern African countries soil erosion and the related problems, such as water quality issues or decreasing soil productivity, are the main topics affecting the inhabitants of both rural and urban areas. Therefore, the attention has been recently placed on those problems related to soil erosion. This can also be documented by an increasing number of studies carried out on erosion and by the development and application of erosion models. Nevertheless, gully erosion phenomena have been widely neglected in erosion modelling. This is because the development of erosion models was focused on those regions with an intense agriculture typical of developed countries on the one hand, and because of the spatial and temporal heterogeneity of gully erosion processes on the other hand. This study regards the identification of gully erosion forms and processes in the Mbuluzi River catchment (Kingdom of Swaziland) by using the Erosion Response Units (ERU) concept. The following modelling of gully erosion was done through the stable gully model [Catena 37 (1999) 401]. The input data were obtained through the application of remote sensing techniques (API method) and GIS-analyses. The example from Swaziland shows that the applied methods are able to identify areas affected by gully erosion. Furthermore, it is possible to estimate the amount of soil loss due to gully erosion, which, for example, is not taken into consideration by the USLE-type models.  相似文献   
87.
Red clover (Trifolium pratense L.) is the third major forage species in Europe, but there is limited information on the biodiversity and the genetic structure of landraces and natural populations which evolved in this region. The objective of this study was producing such information for Italian germplasm on the ground of molecular and morphophysiological diversity. The study included 16 Italian natural populations from a wide range of environments, four landraces representing the four traditional commercial ecotypes, and two varieties. Eight morphophysiological traits were assessed in a replicated trial under field conditions, whereas two AFLPs primer combinations with 140 polymorphic markers were recorded on a random sample of 13 genotypes per population. Ordination and classification results based on morphophysiological data clearly kept track of the type of germplasm (i.e. landrace or natural population) and its geographic origin, unlike results based on molecular markers. Euclidean distances among populations based on morphophysiological traits were not correlated with Nei’s genetic distances based on molecular markers according to Mantel’s test. Geographical distances among landrace or natural population material was correlated with distances based on morphophysiological traits but not with those based on molecular markers. The average within-population variation estimated via molecular markers was about 2.6-fold higher than that among populations, preventing an acceptable discrimination among most populations. On average, natural populations tended to have within-population variation similar to varieties and somewhat lower than landraces. Our results have implications for collection, conservation, exploitation and registration in a sui generis system of red clover genetic resources.  相似文献   
88.
89.
Journal of Pest Science - The development of an integrated rodent pest management strategy requires the adoption of protocols that should be based on a good knowledge of species–habitat...  相似文献   
90.
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