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151.
ABSTRACT

The study aimed to evaluate, in a marginal semi-arid Mediterranean agro-ecosystem (Sicily-Italy), the effects of arbuscular mycorrhizal fungi (AMF) inoculation and raw olive mill wastewater (OMW) (40 and 80 m3 ha?1) on forage (durum wheat-snail medick intercropping) yield, and grain production of broad bean and chickpea. AMF inoculation significantly increased (+13.6%) forage dry biomass and durum wheat nitrogen (+22.8%) and phosphorus (+32.5%) uptake. AMF inoculation, significantly promoted broad bean phosphorus uptake (+11.5%) and root nodule number (+13.9%) in the absence of OMW. OMW spreading reduced weeds in the forage (?31.3%), root nodule number (?29.7%) and dry weight (?22.7%) in broad bean. OMW also significantly increased snail medick dry biomass (+19.3%) as compared to control treatments (0, 40 and 80 m3 H2O ha?1, average production 361 g m?2), and broad bean grain yield with a production of 2.46 ± 0.12 and 1.94 ± 0.09 Mg ha?1 with and without OMW, respectively. During the experiment AMF colonization was not affected by OMW volumes. The results obtained showed that in a marginal Mediterranean agro-ecosystem: 1) OMW, notwithstanding spreading volumes, is a valuable amendment to maximize legume yield while 2) AMF inoculation is a valuable practice to improve biomass production and N and P uptake in wheat.  相似文献   
152.
The ability of fungi to break down complex carbon sources makes them of vital importance in both the generation and application of compost. This paper illustrates the diversity and functions of the mycoflora of both a green compost (made solely thermophilically from plant debris) and a vermicompost (made mesophilically by the action of earthworms on plant and animal wastes). The soil dilution plate technique was applied on 3 media (PDA, CMC, PDA plus cycloheximide) and at 3 incubation temperatures (24°C, 37°C and 45°C) to isolate and identify fungal entities. Enzymatic activities (amylase, cellulase, chitinase, esterase, ligninase, pectinase, phosphatase, plastic degradation and xylanase) of most species from both composts were evaluated with a semiquantitative method on 15 substrates. There were substantial qualiquantitative differences in the species composition of the two composts. A total of 193 entities were isolated: 54 from green compost only, 77 from vermicompost only, 62 from both. This taxonomic diversity was reflected in the metabolic potential. Amilase, cellulase, protease and esterase activities were significantly higher in the green compost. Lignin and plastic polymer degradation were significantly higher in the vermicompost. Structural and functional characterization of this kind is of assistance in determining both the most appropriate application of composts and their hygienic quality.  相似文献   
153.
The degree of decolorization of Poly R-478, a highly recalcitrant anthraquinone dye, by three basidiomycetes belonging to Polyporales isolated from compost was investigated together with the enzymes involved. Decolorization tests in two liquid cultures, one with a simple mycelium inoculum, the other with an inoculum of mycelium grown on straw, resulted in 70% and 87% decolorization respectively in 7 days. However, the efficiency did not increase significantly in the presence of the lignocellulose substrate. The three strains produced laccase and/or manganese peroxidase activity during the decolorization, whereas lignin peroxidase activity was not observed. Previous growth on straw enhanced the synthesis of ligninolytic enzymes, though there was no correlation between enzyme activity and decolorization. The three fungi can be proposed as promising candidates for the treatment of colored industrial effluents and probably for soils contaminated by complex polymers, such as polycyclic aromatic hydrocarbons.  相似文献   
154.
  1. Habitat fragmentation and loss threaten freshwater biodiversity worldwide. Habitats that are essential as fish spawning and nursery sites are critical, and must be identified for conservation purposes. Littoral zones within Patagonian lakes, especially shallow vegetated areas, represent important areas for the Creole perch, Percichthys trucha.
  2. Spawning behaviour has been little studied, so it is not known whether these movements are performed in groups. A particular area of a deep lake in northern Patagonia was studied to identify the environmental conditions under which spawning occurs, and to analyse spawning aggregation behaviour in relation to the lunar cycle.
  3. To identify spawning sites, spawning occurrence time, and the environmental parameters that determine it, fish capture data were analysed. Underwater cameras were also set up at three depth strata in the shallow zone to detect spawning aggregation behaviour. Aggregation was scored as the greatest number of individuals present in a single frame, and the number present per depth stratum. The relationship between the lunar cycle and Creole perch abundance by depth was then determined.
  4. This is the first visual record of a spawning bed and the spawning aggregation behaviour of Creole perch in Patagonian lakes. The abundance of mature Creole perch in the shallow strata during the austral spring suggests that vegetated areas constitute spawning sites. Spawning aggregation takes place at a shallow depth 2 days before the full moon.
  5. As the reproductive behaviours of Creole perch are important phenomena in the life history of the species, the results of this study have important implications for conservation and management.
  相似文献   
155.
To compare the prevalence of intestinal parasites in shelter and hunting dogs in Catalonia, Northeastern Spain, fresh faecal samples from 81 shelter dogs and 88 hunting dogs were collected and analysed by faecal flotation. The overall prevalence of intestinal parasites was 71.6% in each population. In the shelter dog group, 67.9% of dogs were positive for intestinal protozoa and 9.8% were positive for helminths. In the hunting dog group, 20.4% of dogs were positive for intestinal protozoa and 63.6% were positive for helminths. A subset of Giardia-positive samples was evaluated by PCR; Giardia assemblages C or D were detected. These results suggest that comprehensive parasite control measures should be implemented in both shelter and hunting dogs in Catalonia.  相似文献   
156.
It is known that gilt progeny performance is reduced compared with sow progeny. Previous research suggests that the presence of maternal feces in early life improves the health and survival of offspring. Therefore, we aimed to determine whether contact with feces from multiparous (MP) sows would improve the growth and survival of piglets born and reared on primiparous (P1) sows and if so, whether these differences are associated with the gut microbiota. Four treatments were applied for 10 days: Donor (n = 29) piglets had limited access to maternal feces as, each morning, sow feces were removed and placed in the crate of a P1 sow (P1-FT; n = 30 piglets) and P1-Con (n = 29) and MP-Con (n = 33) piglets had access to their own mothers’ feces. All piglets were weighed on days 1, 3, 10, and 18. Fecal samples were collected from a subset of sows (n = 10/treatment) 3 days post farrow and from two female piglets/litter on days 10 and 18 (n = 20/treatment) and subject to 16S rRNA amplicon analysis. Escherichia, Clostridium, Campylobacter, and Treponema were more abundant in MP sows, while P1 sows had a higher abundance of Lactobacillus and Prevotella. At 10 days, P1 progeny fecal microbiota differed, and growth and survival were reduced when compared with MP progeny. No treatment effect was observed for P1-FT piglets (P > 0.05). Donor piglets had a different fecal microbiota and improved weight and survival then all other treatments (P < 0.05). Overall, the removal of sow feces from the farrowing crate improved piglet microbiota development, growth, and survival.  相似文献   
157.
In 2011, five outbreaks of dourine were originally reported in Italy. The outbreaks occurred in two regions of southern Italy. From June to December 2011, a surveillance plan has been carried out in Italy to estimate the prevalence and geographical distribution of dourine infection in the equine population. Finally, two other new outbreaks were reported, and seven outbreaks were confirmed. This article describes the results of the surveillance plan, also taking into consideration the prevalence of infection observed in the different types of equine premises.  相似文献   
158.
159.
Further purification of the apolar extracts of the sponge Plakinastrella mamillaris, afforded a new oxygenated polyketide named gracilioether K, together with the previously isolated gracilioethers E–G and gracilioethers I and J. The structure of the new compound has been elucidated by extensive NMR (1H and 13C, COSY, HSQC, HMBC, and ROESY) and ESI-MS analysis. With the exception of gracilioether F, all compounds are endowed with potent pregnane-X-receptor (PXR) agonistic activity and therefore represent a new chemotype of potential anti-inflammatory leads. Docking calculations suggested theoretical binding modes of the identified compounds, compatible with an agonistic activity on hPXR, and clarified the molecular basis of their biological activities.  相似文献   
160.
The present study addresses the influence of ageing on the bread-making performances of durum wheat semolina by bread image analysis. Bread loaves were produced from semolina samples stored in 4 different packaging materials for up to 150 days. Sampling and bread-making trials were performed every 15 days. Results showed that ageing does affect durum wheat semolina bread-making performances, highlighting that storage time, rather than the type of packaging material, is the main factor determining quality changes in the final bread samples. In particular, a change in the crust colour parameters and a reduction of the bread slice area and height by 20–35% were observed with increasing semolina storage time, along with a slight increase of crust % area. The change in farinographic parameters of dough suggests that the observed reduction of technological quality might be due to increased stiffness and reduced extensibility of gluten occurring in aged semolina. Unlike common wheat flours, which usually improve their technological features during ageing, durum wheat semolina is negatively affected in its quality by storage. The study highlights the importance of considering bread-making performances among the quality parameters to be taken into account for the shelf life evaluation of durum wheat semolina.  相似文献   
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