Volatile compounds of Psidium salutare (H.B.K.) Berg. fruit     

Pino JA  Marbot R  Bello A 《Journal of agricultural and food chemistry》2002,50(18):5146-5148

Volatile compounds were isolated from Psidium salutare fruits by simultaneous steam distillation-solvent extraction according to the Likens-Nickerson procedure. Compounds were identified by capillary GC and GC-MS. One hundred and fifty compounds were identified in the aroma concentrate, from which limonene, myrcene, and alpha-pinene were found to be the major constituents in the fruit.  相似文献   

Nutrient and persistent pollutant deposition on the Bothnian Bay ice and snow fields     

Lars Rahm  Bertil Håkansson  Per Larsson  Elisabet Fogelqvist  Gudrun Bremle  Jorge Valderrama 《Water, air, and soil pollution》1995,84(1-2):187-201

A study of atmospheric deposited nutrients and some persistent pollutants has been carried out on the ice and snow fields of the subarctic Bothnian Bay, the northernmost basin of the Baltic Sea. Total amounts of 600, 500 and 400 tons NO₃-N, NH₄-N and N_org-N, respectively are deposited in the snow while the corresponding amounts for P_tot-P is 40 tons. The corresponding amount for PCB and lindane are 1.0 and 0.2 kg, respectively. The measurements were carried out on the snow-covered ice four to six weeks old. A part of the deposited snow has been incorporated -into the snow-ice and an attempt to estimate its mean thickness and its amount of nutrients has been made. The total amounts now reach 1700, 1300 and 1100 tons of NO₃-N and NH₄-N and N_org-N, respectively in the snow and ice together. The results obtained support the use of land-based stations in estimates of seasonal atmospheric nutrient deposition to the Bothnian Bay. The observed concentrations of chloroorganic compounds correspond to those land-based observations reported from the same latitude in the northern hemisphere and reported in literature.  相似文献   

Pine processionary caterpillar Thaumetopoea pityocampa as a new threat for relict Mediterranean Scots pine forests under climatic warming     

José A Hódar  Jorge Castro  Regino Zamora 《Biological conservation》2003,110(1):123-129

The wide distribution of Scots pine (Pinus sylvestris L.) in Europe includes two relict populations in southern Spain (Sierra Nevada and Sierra de Baza), belonging to the subspecies nevadensis. These populations are isolated in high mountains, which tends to protect them from the attack of a severe defoliating Mediterranean pest, the pine processionary moth Thaumetopoea pityocampa. However, as a consequence of climate change, the pine processionary caterpillar has increasingly attacked populations of this pine in recent years. This work describes the detrimental effects of defoliation by the pine processionary caterpillar in P. sylvestris subsp. nevadensis in Sierra Nevada. Defoliation strongly reduced pine growth as well as all the reproductive parameters measured (female and male cone production, mature cone size, seed production and seed weight), in addition to some deaths. If winter temperatures continue to increase, the pine processionary caterpillar will have a dangerous impact in these relict pine populations, by further reducing the pine's weak regeneration capacity. We suggest some mitigation actions based on managing habitat structure, in order to reduce or avoid such negative impacts.  相似文献   

Assessment of Boron Application in Chestnuts: Nut Yield and Quality     

Ester Portela  Jorge Ferreira-Cardoso  José Louzada  José Gomes-Laranjo 《Journal of plant nutrition》2015,38(7):973-987

A field trial was conducted between 2006 and 2009 in order to quantify the effect of boron (B) application on the yield and quality of chestnuts. The trial was established in an acid soil derived from siliceous schist and two levels of B were applied. Fruit abortion and nut yield per tree were measured, and nut quality parameters and chemical composition of the kernel were determined. Foliar B concentration was 8.6 mg kg^?1 in the control trees and 48.4 mg kg^?1 in fertilized chestnuts. Boron improved fruit setting and promoted nut production by 77%. In 2008, the occurrence of cold temperatures enhanced the effect of B on fruit setting, which was four-fold, whereas with the normal temperatures of 2009 the increase was lower. The drought of 2009 was responsible for the ruinous chestnut caliber and shell cracking. Boron induced a significant increase in the crude fat of chestnut kernel.  相似文献   

Isozyme diversity and analysis of the mating system of the wild rice Oryza latifolia Desv. in Costa Rica     

Tania Quesada  Jorge Lobo  Ana M. Espinoza 《Genetic Resources and Crop Evolution》2002,49(6):633-643

Oryza latifolia is the most abundant and widespread wild relative of rice in the lowlands of Costa Rica. It also has the most diverse morphology. However, little is known about the genetic diversity and mating system of this allotetraploid species. Genetic analyses of nine populations from different life zones from the Pacific and Atlantic slopes were performed using six isozyme loci. Differences in genetic variability were observed among populations, of which Palo Verde and Santa Rosa were the most diverse. Most Atlantic populations clustered together, and a similar result was obtained with the Pacific populations. High levels of interpopulation diversity were observed while most populations were monomorphic for at least one genotype, suggesting little genetic flow within populations. Even in polymorphic populations no variation was observed within progeny groups, combined with Hardy-Weinberg disequilibria in most populations, commonly observed in autogamous species or in species with clonal reproduction. However, the high frequency of heterozygous-like patterns may suggest that the reproductive system of O. latifolia might be more complex. Future research may explain the genetic patterns as well as the reproductive biology of this species. The knowledge of the genetic diversity and mating system of O. latifolia could contribute to the implementation of genetic resource conservation strategies and gene flow analyses, as well as of breeding programs for rice improvement.  相似文献   

Heavy metal and PCB spatial distribution pattern in sediments within an urban catchment—contribution of historical pollution sources     

Celia Dias-Ferreira  Rosinda L. Pato  Jorge B. Varejão  Alexandre O. Tavares  Antonio J. D. Ferreira 《Journal of Soils and Sediments》2016,16(11):2594-2605

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Interactive effect between Cu‐adapted arbuscular mycorrhizal fungi and biotreated agrowaste residue to improve the nutritional status of Oenothera picensis growing in Cu‐polluted soils          下载免费PDF全文

Sebastián Meier  Pablo Cornejo  Paula Cartes  Fernando Borie  Jorge Medina  Rosario Azcón 《植物养料与土壤学杂志》2015,178(1):126-135

The interactive effect of sugar beet (SB) agrowaste and arbuscular mycorrhizal (AM) fungi inoculation in response to increasing Cu levels was evaluated in the metallophyte Oenothera picensis. Plants were grown in a Cu‐added soil (0, 100, or 500 mg Cu kg^?1), in presence or absence of SB, and inoculated with: (1) indigenous Cu adapted mycorrhiza (IM) isolated from Cu‐polluted soils; (2) Claroideoglomus claroideum (CC); or (3) maintained uninoculated (control). Sugar beet application produced an increase in shoot biomass of 2 to 7 times, improving plant nutritional status and allowing their survival at the highest Cu concentrations. Moreover, AM fungi utilization had a positive effect promoting the plant establishment; nevertheless, Cu plant concentration as well as the mycorrhizal development in terms of AM colonization, AM spore density, and glomalin production were strictly dependent of the AM fungi strains used. Remarkable differences between AM fungi strains were observed at the highest soil Cu level where only plants colonized by IM were able to survive and grow when no SB residue was added. An interactive effect between AM fungi and SB produced a higher plant growth than plants without the amendment application, improving the plant establishment and allowing their survival at highest copper concentrations, suggesting that this combination could be used as a biotechnological tool for the phytoremediation of Cu‐polluted soils.  相似文献   

PRENATAL SONOGRAPHIC DIAGNOSIS OF FETAL DEATH AND HYDRANENCEPHALY IN TWO CHIHUAHUA FETUSES     

RobertDe  J. Cruz  DVM  Manuel S.  Alvarado  DVM  MS  Jorge E.  Sandoval  DVM  Eloina  Vilchez  DVM 《Veterinary radiology & ultrasound》2003,44(5):589-592

Hydranencephaly and fetal death was diagnosed in two of three fetuses during the abdominal sonographic examination of a 2.5-year-old, intact female Chihuahua that had clinical signs of dystocia 63 days after mating. A cesarean section was performed and one live normal puppy was present. Two dead puppies, each with a markedly enlarged and fluid filled skull were removed.  相似文献   

Simulation of Potato Late Blight in the Andes. I: Modification and Parameterization of the LATEBLIGHT Model     

Andrade-Piedra JL  Hijmans RJ  Forbes GA  Fry WE  Nelson RJ 《Phytopathology》2005,95(10):1191-1199

ABSTRACT LATEBLIGHT, a mathematical model that simulates the effects of weather, host growth and resistance, and fungicide use on asexual development and growth of Phytophthora infestans on potato foliage, was modified so that it can be used in the Andes and, eventually, worldwide. The modifications included (i) the incorporation of improved equations for the effect of temperature on lesion growth rate (LGR) and sporulation rate (SR); (ii) the incorporation of temperature-dependent latent period (LP); and (iii) the use of experimentally measured parameters of LGR, SR, and LP for specific potato cultivars and pathogen lineages. The model was parameterized for three Peruvian potato cultivars (Tomasa, Yungay, and Amarilis) infected with isolates of a new clonal lineage of P. infestans that is currently predominant in Ecuador and Peru (EC-1).  相似文献   

2005 Guidelines for the diagnosis, prevention and management of heartworm (Dirofilaria immitis) infection in dogs   总被引：2，自引：0，他引：2  

Nelson CT  McCall JW  Rubin SB  Buzhardt LF  Dorion DW  Graham W  Longhofer SL  Guerrero J  Robertson-Plouch C  Paul A;Executive Board of the American Heartworm Society 《Veterinary parasitology》2005,133(2-3):255-266

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