Multivariate analysis of invasive plant species distributions in southern US forests     

Lázaro-Lobo  Adrián  Ramirez-Reyes  Carlos  Lucardi  Rima D.  Ervin  Gary N. 《Landscape Ecology》2021,36(12):3539-3555

Landscape Ecology - Invasive plants cause significant impacts in forested areas throughout the world. However, little is known about the relative importance of environmental drivers on the...  相似文献   

Prevalence of antibodies to Borrelia burgdorferi sensu lato in southern chamois (Rupicapra pyrenaica) in Spain     

Ortuño A  Castellà J  Marco I  Ruiz M  Lavín S 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2003,50(5):253-254

Ungulates are involved in the epidemiology of Borreliosis as maintenance hosts for vector tick species. We evaluated the prevalence of antibodies to Borrelia burgdorferi sensu lato in two different populations of southern chamois in Spain. Forty-six sera (40.4%) were positive at titres >/=1 : 64 using an indirect immunofluorescence assay (IFAT).  相似文献   

Effects Of Thinning In a Water-Limited Holm Oak Forest     

Romà Ogaya  Anna Escolà  Daijun Liu  Adrià Barbeta  Josep Peñuelas 《Journal of Sustainable Forestry》2020,39(4):365-378

ABSTRACT

A natural holm oak forest was selectively thinned to test thinning as a tool to reduce tree mortality, increase productivity, and reverse the recent regression of the dominant species (Quercus ilex) induced by climate change. Thinning increased aboveground productivity and reduced stem mortality in this Mediterranean forest during four years just after thinning, contributing to the maintenance of forest functioning under changing climatic conditions. Q. ilex was the only species positively affected by the thinning: stem growth increased for all stem sizes, and mortality was significantly lower in thinned plots. On the contrary, mortality rates of Phillyrea latifolia and Arbutus unedo were not significantly lower. Stem growth increased for P. latifolia only in the smallest stem-size class. Our results highlight the suitability of selective thinning for improving the forest productivity and ensuring the conservation of Mediterranean coppices. Other benefits of selective thinning, such as a decrease in the risk of fire dispersion and an increase in the water supply for human populations, are also discussed.  相似文献   

Implications of landscape configuration on understory forage productivity: a remote sensing assessment of native forests openings     

Trinco  Fabio Daniel  Rusch  Verónica Elena  Howison  Ruth Alison  Garibaldi  Lucas Alejandro  Tittonell  Pablo Adrián 《Agroforestry Systems》2021,95(8):1675-1688

Agroforestry Systems - Sound management of native forests used for cattle grazing requires understanding the dynamics of forage productivity in the openings. Despite their importance, forage...  相似文献   

Supplementation of Citric Acid and Amino Acid Chelated Trace Elements in Low‐Fish Meal Diet for Rainbow Trout Affect Growth and Phosphorus Utilization     

Adrián J. Hernández  Shuichi Satoh  Viswanath Kiron 《Journal of the World Aquaculture Society》2012,43(5):688-696

This study was conducted to evaluate the effect of citric acid (CA) and amino acid chelated trace elements (AA) on the growth, phosphorus (P) utilization efficiency and loading in rainbow trout fed a diet formulated with a low‐fish meal (FM) concentration. A low‐FM basal diet with or without monocalcium phosphate supplementation served as positive and negative control correspondingly. Dietary treatments consisted of the basal diet supplemented either with 1% CA, AA (equivalent to 40 Zn, 20 Mn, and 4 Cu mg/Kg of diet instead of inorganic trace element mix) or a combination of both. Duplicate groups of 35 fish (13.2 g) were fed until apparent satiation during 12 wk. Group of fish fed diets supplemented with 1% CA or AA had a final growth and feed utilization similar to that observed in fish fed the positive control diet (P > 0.05). P absorption was increased with the addition of CA or AA. P retention efficiency rates for these diets were higher in comparison with the rest of the treatments consequently showing the lowest P loading values (P < 0.05). The results indicate that addition of 1% CA or AA, to a low‐FM diet without inorganic P supplementation enhanced fish growth, P retention, and decreased P load to the environment.  相似文献   

Utilization of genetic resources for the introduction and adaptation of exotic vegetable crops: The case of pepino (Solanum muricatum)     

Jaime Prohens  Adrián Rodríguez-Burruezo  Fernando Nuez 《Euphytica》2005,146(1-2):133-142

Summary Pepino (Solanum muricatum), a vegetatively propagated plant from the Andean region used for its edible fruits, has been identified as a potential crop for greenhouse cultivation in Mediterranean regions. However, attempts for introducing it have been unsuccessful, either because of the low yield, poor fruit quality, or both. Screening of germplasm under Mediterranean conditions showed that sources of variation for high yield existed in the cultivated genepool and that wild species S. caripense and S. tabanoense could contribute to a considerable improvement of soluble solids content (SSC) of pepino. Progenies obtained after crossing genetically distant (AFLP-based) parental clones were heterotic for yield, and allowed the selection of clones with an improved combination of yield and SSC. As a result of this intraspecific programme, two new improved cultivars (‘Turia’ and ‘Valencia’), which outperform the rest of cultivars available, have been selected for cultivation in Mediterranean conditions. The interspecific programme involved the selection of clones with high yield and SSC in backcross generations. The results show that introgression of genes from the wild species can contribute to improve the SSC of pepino. The backcross programme is in an advanced stage and new cultivars derived from the interspecific crosses are expected to be released in a near future. New prospects for the future in pepino breeding include the genetic transformation, the establishment of a genetic map, and the use of the genomic information from related Solanaceae important crops. All the information obtained is illustrative for the breeding for adaptation of vegetatively propagated crops.  相似文献   

Foam aptitude of trepat and monastrell red varieties in cava elaboration. 2. Second fermentation and aging     

Girbau-Solà T  López-Barajas M  López-Tamames E  Buxaderas S 《Journal of agricultural and food chemistry》2002,50(20):5600-5604

The foam properties of sparkling wines (Cava) made from two red autochthonous grape varieties, Trepat and Monastrell, and coupages, including different percentages of them, were studied during second fermentation and aging. The effect of second fermentation on foam gave the highest decreases when the base wines had the highest foam values, while gave the lowest decreases or even increases for the base wines with the lowest foam characteristics. However, the greater the HM and Sigma of the base wine, the greater the foam values of the sparkling wine. Base wine determinations for quality control in cellars could provide information about future sparkling wine foaming. Acidity parameters, ethanol, sulfur, and polysaccharides contents were correlated to foam characteristics in the sparkling wines. In terms of color and foaming, wines made from the red varieties Trepat and Monastrell blended with white variety wines could be appropriate for elaborating "blanc de noirs" sparkling wines.  相似文献   

A green algal apicoplast ancestor     

Funes S  Davidson E  Reyes-Prieto A  Magallón S  Herion P  King MP  González-Halphen D 《Science (New York, N.Y.)》2002,298(5601):2155

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Bacterial rhodopsin: evidence for a new type of phototrophy in the sea     

Béjà O  Aravind L  Koonin EV  Suzuki MT  Hadd A  Nguyen LP  Jovanovich SB  Gates CM  Feldman RA  Spudich JL  Spudich EN  DeLong EF 《Science (New York, N.Y.)》2000,289(5486):1902-1906

Extremely halophilic archaea contain retinal-binding integral membrane proteins called bacteriorhodopsins that function as light-driven proton pumps. So far, bacteriorhodopsins capable of generating a chemiosmotic membrane potential in response to light have been demonstrated only in halophilic archaea. We describe here a type of rhodopsin derived from bacteria that was discovered through genomic analyses of naturally occuring marine bacterioplankton. The bacterial rhodopsin was encoded in the genome of an uncultivated gamma-proteobacterium and shared highest amino acid sequence similarity with archaeal rhodopsins. The protein was functionally expressed in Escherichia coli and bound retinal to form an active, light-driven proton pump. The new rhodopsin exhibited a photochemical reaction cycle with intermediates and kinetics characteristic of archaeal proton-pumping rhodopsins. Our results demonstrate that archaeal-like rhodopsins are broadly distributed among different taxa, including members of the domain Bacteria. Our data also indicate that a previously unsuspected mode of bacterially mediated light-driven energy generation may commonly occur in oceanic surface waters worldwide.  相似文献   

Factors that contribute to the mycoparasitism stimulus in Trichoderma atroviride strain P1          下载免费PDF全文

Woo S L　 Formisano E　 Fogliano V　 Cosenza C　 Mauro A　 Turrà D　 Soriente I　 Ferraioli S　 Scala F　 Lorito M 《浙江大学学报(农业与生命科学版)》2004,30(4):421-421

Trichoderma atroviride strain P1 has been used extensively to study the mycoparasitic mechanisms in the interaction between plant pathogenic host and beneficial antagonistic fungi. Mutants of P1 containing the green fluorescent protein (gfp) or glucose oxidase (gox) reporter systems and different inducible promoters (from the exochitinase nag1 gene, or the endochitinase ech42 gene of P1) were used to determine the factors that activate the biocontrol gene expression cascade in the antagonis…  相似文献