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81.
Tamara Eckhart Severin Walcher Hubert Hasenauer Marcela van Loo 《European Journal of Forest Research》2017,136(5-6):811-825
Due to its productivity and potential to adapt to the expected climate change, the Douglas-fir is one of the most important commercial non-native forest tree species in Europe. Currently, seeds from both non-native European and native American seed stands are used for plantations. In this study, we investigate European seed lots for their native origin (variety and potential geographic origin in America) and assess the adaptability, growth and survival potential of European versus American Douglas-fir seed lots. We compare the genetic diversity, morphological characteristics such as height (h), root collar diameter (rcd) and the ratio of h/rcd, and the timing of bud burst. We investigate 852 1-year-old seedlings from 10 different US and European seed lots representing 5 provenance regions which are sold in Germany and Austria. Seedlings are genotyped for 13 nuclear SSRs and analysed together with reference data set and standard genetic structuring and assignment methods. Adaptive traits of morphological characteristics and timing of bud burst of the seedlings are recorded and statistically analysed. The results show that the investigated European seedlings originate from recommended American native seed sources and represent both varieties and inter-varietal admixed individuals. European seedlings have a lower genetic diversity versus the American seedlings and native populations. They show significant differences in the adaptive traits such as morphological characteristics and timing of bud burst. According to the genetic diversity indices, certified North American Douglas-fir seed sources should be preferred for planting in Central Europe. 相似文献
82.
A female ring-tailed lemur (Lemur catta) and her two cubs held in a zoo in Chile exhibited signs of severe hepatic insufficiency. In spite of supportive treatment, the three animals died a few days after the onset of signs. Postmortem examination revealed ascites and fibrotic lesions in the liver of all the individuals. Histologically, the liver of two of them showed a severe parasitic ova infection and lipidosis, the morphologic characteristics of the parasitic ovas were consistent with Capillaria hepatica (syn. Calodium hepatica) eggs. To the authors' knowledge, this is the first clinical case report of hepatic capillariasis in prosimians, and its implications are discussed. 相似文献
83.
de Pinho Manzi M Nóbrega DB Faccioli PY Troncarelli MZ Menozzi BD Langoni H 《Research in veterinary science》2012,93(1):430-434
The aims of the present study were to relate intramammary infection (IMI) occurrence and somatic cell count (SCC) with teat-end condition (TEC) and udder cleanliness (UC). Milk samples from 1931 teats were evaluated according to the presence of IMI and SCC. Scores were applied to teats according to the TEC and to UC. Teats ends with a very rough ring had the largest number of IMI when compared to the other three categories, as well as animals with dirtier udders. The change in a TEC score increased by around 30% the chance of IMI. Also, the chance of the animal developing IMI increased by approximately 47% when the UC score increased. No significant association between both scores and quarter SCC was found. It can be concluded that animals with very rough teat end rings and very dirty udders have a greater predisposition to IMI. 相似文献
84.
David Santiago‐Ramos Juan de Dios Figueroa‐Crdenas Jos Juan Vles‐Medina Rosa María Mariscal‐Moreno Rosalía Reynoso‐Camacho Minerva Ramos‐Gmez Marcela Gaytn‐Martínez Eduardo Morales‐Snchez 《Cereal Chemistry》2015,92(2):185-192
The objective of this work was to study the formation of resistant starch (RS) in tortillas from an ecological nixtamalization process compared with the traditional nixtamalization process. The RS increased through all the steps of tortilla production. It was found that the increase of the RS corresponds mainly to the formation of RS5 (V‐amylose‐lipid complex), but in tortillas two major types of RS coexist: RS5 and RS3 (retrograded starch). In general, tortillas from the ecological nixtamalization process gave higher values of protein, lipids, total dietary fiber, insoluble fiber, soluble fiber, and RS compared with tortillas from the traditional nixtamalization process and commercial flour. The highest glycemic index (GI) occurred in the tortillas from commercial flour, whereas tortillas from 0.4% CaCO3 and 0.6% CaSO4 were classified as medium‐GI (GI 50–70). Tortillas from 0.6% CaCl2 had the lowest value of GI. The ecological nixtamalization processes caused significant differences in quality and nutritional properties of tortillas. 相似文献
85.
Marcela A. Rodríguez Tânia MarquesDolors Bosch Jesús Avilla 《Pesticide biochemistry and physiology》2011,100(2):151-159
Spanish Cydia pomonella (L.) field populations have developed resistance to several insecticide groups. Diagnostic concentrations were established as the LC90 calculated on a susceptible strain (S_Spain) for five and seven insecticides and tested on eggs and neonate larvae field populations, respectively. The three most relevant enzymatic detoxification systems (mixed-function oxidases (MFO), glutathione S-tranferases (GST) and esterases (EST)) were studied for neonate larvae.In eggs, 96% of the field populations showed a significantly lower efficacy when compared with the susceptible strain (S_Spain) and the most effective insecticides were fenoxycarb and thiacloprid. In neonate larvae, a significant loss of susceptibility to the insecticides was detected. Flufenoxuron, azinphos-methyl and phosmet showed the lowest efficacy, while lambda-cyhalothrin, alpha-cypermethrin and chlorpyrifos-ethyl showed the highest. Biochemical assays showed that the most important enzymatic system involved in insecticide detoxification was MFO, with highest enzymatic activity ratios (5.1-16.6 for neonates from nine field populations). An enhanced GST and EST activities was detected in one field population, with enzymatic activity ratios of threefold and fivefold for GST and EST, respectively, when compared with the susceptible strain. The insecticide bioassays showed that the LC90 used were effective as diagnostic concentrations. Measures of MFO activity alongside bioassays with insecticide diagnostic concentrations could be used as tools for monitoring insecticide resistance in neonate larvae of C. pomonella. 相似文献
86.
Frynta D Eliášová B Fraňková M Aulický R Rödl P Stejskal V 《Pest management science》2012,68(3):355-361
BACKGROUND: The authors investigated whether fluorescent pigment in thermoset melamine microcapsules incorporated into monitoring baits would be excreted in the faeces of wild house mice in a quantity and intensity that would be detectable by a human observer. RESULTS: Experimental mice produced 24–116 UV‐visible faecal pellets per 24 h; the mean dry weight was 582 mg. The number and weight of the faeces was independent of mouse sex and weight. The defecation of UV‐visible faeces began at 2–3 h, peaked at 5–8 h and was complete at 17 h after bait ingestion. The detectability of the highly fluorescent faecal pellets using a small UV flashlight approached 100%, and no false positives were recorded. CONCLUSION: The tested formulation is of significant value for rodent pest monitoring because faeces that are highly visible by UV light are produced for 15 h by mice after ingestion, and their detection is easy and unambiguous. Copyright © 2011 Society of Chemical Industry 相似文献
87.
Salvador A. Solís‐Chávez Manuel A. Castillo‐Rivera Marcela Arteaga‐Silva Alejandra Ibáñez‐Contreras Braulio Hernández‐Godínez Andrés Morón‐Mendoza Gamaliel Mendoza‐Cuevas Axayácatl Morales‐Guadarrama Emilio Sacristan‐Rock 《Veterinary radiology & ultrasound》2018,59(5):545-550
Osteopathologies are a result of advanced age and decreased bone density and represent a global health problem. It is therefore important to generate models for longitudinal studies of the pathophysiology in order to improve early diagnosis and develop preventive therapies. For this kind of research, the use of computed tomography (CT) to evaluate bone health offers advantages over other techniques since it provides more complete information. The aim of this prospective, pilot study was to obtain measurements of the left femur from a population in captivity of 32 rhesus monkeys (Macaca mulatta) in order to standardize the model for future research. Healthy subjects from 5 to 28 years old were chosen. Three groups with different ages were formed as follows: (1) 5–9 years, (2) 10–19 years, and (3) 20–28 years. Semi‐automatic segmentation by threshold defined the regions of interest, which were subdivided in the range of 300–700 Hounsfield units (HU) for trabecular bone and >700 HU for cortical bone. Then, the proportional ratios of the volumes of trabecular bone and cortical bone were obtained. Significant differences (analysis of variance test) in the averages of Hounsfield units, cortical, and trabecular bone proportions from each age group proved that a decrease in bone density begins at approximately 20 years of age. The values presented here, as well as the method to obtain them from CT scans, can be used as a baseline in a primate model for long‐term research in bone pathology diagnosis and treatment. 相似文献
88.
Mirande Luciana Desneux Nicolas Haramboure Marina Schneider Marcela Inés 《Journal of pest science》2015,88(1):155-162
Journal of Pest Science - Harmonia axyridis Pallas is a generalist predator native to Asia. It has been released both for classical and neoclassical biological control programs worldwide. Its... 相似文献
89.
This paper investigates the distribution of arbuscular mycorrhizal fungi (AMF) spores and AMF colonization in a field study
in southeastern Brazil. Response to AMF and rhizobial inoculation was studied in monocultures of Plathymenia reticulata and mixed plantations with both Tabebuia heptaphylla and Eucalyptus camaldulensis in a sandy soil during two consecutive years. P. reticulata height and diameter and mycorrhizal colonization and AMF diversity were measured in dry and rainy periods. The inoculated
treatment of E. camaldulensis, T. heptaphylla and P. reticulata mixed plants showed higher height and diameter growth of P. reticulata used as well as increased root colonization and AMF spore numbers. Spore populations were found to belong to five genera:
Acaulospora, Entrophospora, Glomus, Gigaspora and Scutellospora, with Glomus dominating. Agroforestry practices including use of leguminous tree P. reticulata effectively maintained AMF spore numbers in soils and high AMF colonization levels compared with monocultures, proving an
efficient system for productivity and sustainability. 相似文献
90.
Marcela C. Pagano Marta N. Cabello Antonio F. Bellote Nadja M. Sá Maria Rita Scotti 《Agroforestry Systems》2008,74(3):231-242
For the purpose of reforestation and wood supply the leguminous tree Anadenanthera peregrina, a native species, was intercropped with Eucalyptus camaldulensis in a degraded semiarid area of Brazil. Single and mixed stands of these species were inoculated with Rhizobium and/or arbuscular mycorrhizal fungi (AMF). The growth of all species in mixed stands did not differ from those cultivated
in monoculture and land equivalent ratio (LER) exceeded unity in intercropped plots. Inoculated plants showed greater height
and diameter growth and dry matter and nutrient concentration in plants of A. peregrina was higher in inoculated single plots. The distribution, composition and density of AMF species was related to the rhizosphere
effect of plant species. The intercropped model where all the plants were inoculated achieved soil AMF diversity patterns
similar to those of the preserved area and showed also higher soil organic matter, nutrient content as well as a reduction
in soil macroporosity. This model of intercropping may be considered as an efficient system for reforestation under semiarid
conditions. 相似文献