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排序方式: 共有105条查询结果,搜索用时 31 毫秒
71.
72.
Sara Fondevilla Nuno F. Almeida Zlatko Satovic Diego Rubiales Maria C. Vaz Patto José I. Cubero Ana M. Torres 《Euphytica》2011,182(1):43-52
In a previous study a genetic map had been developed using a RIL population derived from a cross between the Pisum sativum ssp. syriacum accession P665 and the P. sativum ssp. sativum cv. Messire. This population segregated for several agricultural important traits and was successfully used to identify QTLs
(Quantitative Trait Loci) controlling resistance to Mycosphaerella pinodes and Orobanche crenata, earliness, root length and aerial biomass. However, this map contained only a few markers in common with the international
pea consensus map, hampering comparison with other pea maps. The objective of this study was to incorporate a set of common
transferable and reproducible markers into the P665 × Messire map to favour comparative mapping and QTL validation. Seventy-eight
out of the 248 SSRs assayed resulted polymorphic in the parental lines. Thirty-eight of them, uniformly distributed all over
the genome, were genotyped in the whole population and included in the map. This SSR enriched map allowed identification of
six new QTLs (three for resistance to M. pinodes, two for resistance to broomrape and one for root length). Inclusion of the SSRs confirmed the homology of some of the QTLs
identified in the population P665 × Messire with other QTLs associated with related traits in different pea genetic backgrounds. 相似文献
73.
74.
The Portuguese silvo-pastoral system montado is broadly classified as a High Nature Value (HNV) system since it corresponds to farmland hosting high biodiversity levels, and such biodiversity depends on specific land use practices. However, in recent decades a decline both in the total montado area and in the tree cover density within the montado has been observed, driven mainly by management changes. This decline may result in biodiversity loss. Grazing is a central aspect determining the long-term sustainability of the montado system and it has implications also on the montado structural diversity, particularly on connectivity and heterogeneity, which is crucial for the maintenance of montado HNV. The aim of this paper is to demonstrate how variations in montado structural diversity are correlated with grazing management and its implications on the value of the system for conservation. The empirical data derives from a case study composed of 41 montado farms in two municipalities of the Alentejo region. Data on grazing management, biophysical and spatial factors were collected and several metrics were calculated to assess montado fragmentation and heterogeneity. A multivariate analysis was performed using generalized additive models. Results show that different grazing patterns, depending on stocking density and grazing animal type, are correlated with variations in montado fragmentation and heterogeneity. Particularly, cattle’s grazing is shown to have adverse effects on the montado fragmentation, while sheep grazing is shown to have stronger impacts on the heterogeneity within the montado patches. 相似文献
75.
Biologic and molecular characterization of Toxoplasma gondii isolates from pigs from Portugal 总被引:2,自引:0,他引:2
de Sousa S Ajzenberg D Canada N Freire L da Costa JM Dardé ML Thulliez P Dubey JP 《Veterinary parasitology》2006,135(2):133-136
Little is known of Toxoplasma gondii infections in animals in Portugal. In the present paper, we report the first isolation of viable T. gondii from pigs in Portugal. Antibodies to T. gondii were found in 52 (15.6%) of 333 pigs prior to slaughter using the modified agglutination test (MAT) at a serum dilution of 1:20. Attempts were made to isolate T. gondii from 37 seropositive pigs. Samples of brain and/or heart from each pig were digested in acid pepsin, and bioassayed into mice. Viable T. gondii was isolated from 15 pigs. Restriction fragment length polymorphism on products of SAG2 locus amplified by PCR and microsatellite analysis revealed that 11 isolates were Type II and four were Type III. The results indicate that phenotypically and genetically T. gondii are similar to isolates from pigs from the U.S. 相似文献
76.
Isolation and structural characterization of new anthocyanin-derived yellow pigments in aged red wines 总被引:1,自引:0,他引:1
He J Santos-Buelga C Silva AM Mateus N de Freitas V 《Journal of agricultural and food chemistry》2006,54(25):9598-9603
Two newly formed yellow pigments that revealed unique spectral features were detected and isolated from an aged Port red wine by TSK Toyopearl HW-40(s) gel chromatography and characterized by UV-visible spectrophotometry, 1H NMR and 13C NMR, and mass spectrometry (LC-ESI/MS). The UV-vis spectra of these pigments showed maximum absorption at 478 nm that is significantly hypsochromically shifted from those of original grape anthocyanins and other pyranoanthocyanins, exhibiting a more yellow hue in acidic solution. The structures of these pigments correspond to methyl-linked pyranomalvidin 3-glucoside and its respective coumaroyl glucoside derivative. They were shown to arise from the reaction between acetoacetic acid and genuine grape anthocyanins. Isolation and NMR identification using 1D and 2D NMR techniques are reported for the first time for this new family of anthocyanin-derived yellow pigments occurring in red wines. 相似文献
77.
Adelaide Perdigão José Pereira Nuno Moreira Henrique Trindade João Coutinho 《Archives of Agronomy and Soil Science》2017,63(11):1546-1555
The soil incorporation of green manures is a practice that can be used in sustainable agriculture and in organic farming, where nitrogen (N) sources are limited. The aim of this study was to evaluate balansa clover (Trifolium michelianum Savi), yellow lupine (Lupinus luteus L.) and ryegrass (Lolium multiflorum Lam.) as potential alternative N sources. A total of nine treatments were considered in this study: control, aerial of balansa clover, roots of balansa clover, aerial of yellow lupine, roots of yellow lupine, aerial of ryegrass, roots of ryegrass, mixture aerial + roots of yellow lupine and mixture aerial + roots of ryegrass. A laboratory incubation experiment was conducted under controlled conditions during 196 days and carbon and N mineralisation were followed. Results showed that green manures are appropriate N sources for Mediterranean farming. No significant differences in terms of N mineralisation were observed between aerial or roots biomass of the green manures. Besides, 37–55% of total N applied was mineralised in treatments amended with balansa clover or yellow lupine, whereas 13–21% of total N applied was mineralised in ryegrass. It can be concluded that the most efficient green manure for supplying mineral N to the succeeding crop was yellow lupine. 相似文献
78.
T. Pinto-Correia N. Guiomar M.I. Ferraz-de-Oliveira E. Sales-Baptista J. Rabaça C. Godinho N. Ribeiro P. Sá Sousa P. Santos C. Santos-Silva M.P. Simões A.D.F. Belo L. Catarino P. Costa E. Fonseca S. Godinho C. Azeda M. Almeida M. Vaz 《Strength and Conditioning Journal》2018,71(5):612-625
Due to their complex structure and traditional low-intensity management, Portuguese oak woodland rangelands known as montados are often considered high nature value (HNV) farming systems, and as such, they may be deemed eligible for subsidies and incentives by governmental and nongovernmental agencies. Too little is known about how the HNV concept might be applied to conserve complex silvopastoral systems. These systems, due to their structural and functional complexity at multiple scales, tend to support high levels of biodiversity. Montados are in sharp decline as a result of the rapid specialization of land management that, through simplification, undermines multifunctionality. Understanding how changes in management influence these systems and their biodiversity is needed for prioritizing conservation efforts and for ensuring they remain HNV systems. On the basis of a field survey in 58 plots distributed among 29 paddocks on 17 farms, we conducted an integrated analysis of the relationship between grazing intensity and biodiversity in montados of similar biophysical and structural characteristics. Data on management were obtained through interviews, and biodiversity data (vegetation, macrofungi, birds, herpetofauna) were obtained through specific field protocols. Additional spatial data, such as soil characteristics, slope, land cover, and linear landscape elements, were also analyzed. The results show no overall biodiversity variation as a result of different management practices. However, different groups of species react differently to specific management practices, and within a pasture, grazing impacts are heterogenous. In low grazing intensity plots, macrofungi species richness was found to be higher, while bird species richness was lower. Using tree regeneration as proxy for montado sustainability, results show less tree regeneration in areas with higher forage quality and more intense grazing. Pathways for future progress are proposed, including creating areas within a paddock that attract grazing away from where regeneration is desired. 相似文献
79.
Miguel S. Lima Júlia M. Silveira Nuno Carolino Luis P. Lamas Rita A. Pascoal Charles A. Hjerpe 《Irish veterinary journal》2015,69(1):16
Background
Pregnancy toxaemia (PT) is a disease that affects pregnant goats during their last month of gestation and is characterized by a high case fatality rate. This study involved 32 does maintained on a commercial dairy goat farm that were diagnosed with PT. A physical examination was performed on and haematology parameters obtained from each doe, at the time of diagnosis. The data from the 24 PT goats that died was compared with the corresponding data from the 8 PT goats that survived.Results
Polypnea, swollen limbs, anorexia with absence of ruminal motility, recumbency, nervous signs and drooping ears were the most frequently observed clinical manifestations. Nineteen out of 21 recumbent goats died. Sixteen out of 17 goats with anorexia and absence of ruminal motility died. Mean beta-hydroxybutyric acid (BHBA) values in the goats that died were not significantly different from those in goats that survived. The blood values for pH and pCO2 (p?<?0.005) as well as for HCO3 ?, BE and K+ (p?<?0.001) were significantly lower in the goats that died than in those that survived.Conclusions
The clinical signs most indicative of a poor prognosis are anorexia with absence of ruminal motility and recumbency. Among the blood parameters to be considered, hypokalaemia and metabolic acidosis are the most relevant. Goats with PT have a high mortality and their condition can deteriorate very fast. Based on the authors’s experience, a good strategy to minimize the economic losses caused by PT is to focus on the offspring survival rate since an early decision (induction of kidding or caesarian surgery) can increase the number of alive kids.80.
Adults from spider crab, Maja brachydactyla, Balss, 1922 were kept in captivity for up to 2 years. Haemolymph of ten females was extracted monthly for monitoring several metabolites and the presence of Vibrionacea bacteria. A neurotoxic marker and hepatic metabolic and digestive enzyme capacities were contrasted between wild specimens and those reared in captivity. As a result, no differences were observed in hepatosomatic index (HSI) between males and females, but captive animals presented lower HSI than the wild ones. After 2 years of confinement, no changes in quantities of haemolymph microflora and metabolites were observed and this was considered indicative of adaptation of the broodstock to confinement. Spider crab also showed a large plasticity in their hepatopancreatic digestive capabilities suggested by the adaptation to the food supplied in captivity. Moreover, captivity conditions did not seem to negatively alter their antioxidant defences, xenobiotic capacity or neuromuscular activity, as no enhanced oxidative stress damage was shown in either males or females. These results indicate that although the confinement conditions used in this study do not mimic those from the wild, they could be considered as adequate for rearing M. brachydactyla in captivity, at least with regard to the set of parameters assessed. 相似文献