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501.
Amanda de la Torre Cesar López Eliana Yglesias Jonathan P. Cornelius 《Forest Ecology and Management》2008
Cedrela odorata L., one of the most important neotropical timber species, is threatened by deforestation and unsustainable logging in many parts of its natural range. Information on patterns of genetic variation is useful in informing both reforestation and genetic conservation activities. However, to date, no such information is available in Peru or elsewhere in South America. In the present study, genetic diversity between and within nine Peruvian populations of the species, based on amplified fragment length polymorphism (AFLP) markers, is reported. Overall diversity level was high (Ht = 0.22), as expected for a widespread, long-lived tropical species, and consistent with previous studies carried out in Central America. Levels of intrapopulation diversity were higher than those previously reported for the species (Hs = 0.13–0.21). Analysis of molecular variation revealed genetic differences between two population groups located on different rivers and between populations located on the same rivers. Differences between groups were greater than those within groups. Genetic and geographical distances were significantly correlated. The relatively strong genetic differences between populations may be related to the riparian, essentially one-dimensional spatial distribution pattern of the populations studied. No difference was found in percentage of polymorphic loci between relatively undisturbed and logged populations. The existence of appreciable genetic differentiation over a relatively small part of the species range in the Peruvian Amazon suggests the need for caution in use of seed outside its zone of origin. For genetic conservation purposes, it would probably be prudent to sample (ex situ) or conserve (in situ) populations in each of the major watersheds of the Peruvian Amazon. 相似文献
502.
Ritva Repo-Carrasco-Valencia Alexander Acevedo de La Cruz Julio Cesar Icochea Alvarez Heikki Kallio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(2):94-101
Cereals provide a good source of dietary fibre and other important compounds with nutritional potential, such as phenolic compounds, antioxidants, minerals and vitamins. Although native Andean cereals are known to have high nutritional value, their minor components have not been studied thoroughly. In this study, two varieties of a native Andean crop, kañiwa (Chenopodium pallidicaule), were investigated as sources of dietary fibre and specific antioxidant compounds. Two products, an extrudate and bran, were also prepared and their functional properties and bioactive compounds were determined. Both varieties were rich in total dietary fibre and lignin, and the phenolic components analyzed had high antioxidant activity. The extrudates had good functional properties, such as degree of gelatinization, sectional expansion index and water solubility index; the bran was high in bioactive compounds, such as total phenolics. In conclusion, kañiwa may offer an alternative to traditional cereals as a health-promoting food ingredient. 相似文献
503.
Marcio Costa Rebecca Di Pietro Jos Antonio Bessegatto Priscilla Fajardo Valente Pereira Fernanda C. Stievani Roberta Gaberlini Gomes Júlio A. N. Lisba J. Scott Weese 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(10):1123
The purpose of this study was to characterize the fecal microbiota of horses with acute and chronic diarrhea before and after fecal microbiota transplantation (FMT). Six client-owned horses with acute and chronic diarrhea received FMT from 2 healthy donor horses. Microbiota analysis using next-generation sequencing was performed on fecal samples collected before and 2 and 7 d after FMT. Signs of diarrhea improved in 4 horses, whereas the remaining 2 horses did not survive. There was a significant difference in the number of bacterial species between donors and recipients (P < 0.05). The Order Lactobacillales and the genera Lactobacillus, Intestinimonas, and Streptococcus were increased in the microbiota of diarrheic horses, and Saccharofermentans genus increased in healthy donors. The results suggest that FMT from the healthy donors was not effective over a 7-day period as it did not change the fecal microbiota of the diarrheic horses. Further research to improve the efficacy of FMT in horses is needed. 相似文献
504.
505.
Marcos Tucunduva de Faria Maria Fernanda Cury-Boaventura Lucia Rossetti Lopes José Roberto Machado Cunha da Silva 《Fish physiology and biochemistry》2014,40(2):445-455
Prochilodus lineatus (curimbatá), from the Procholodontidae family, is a Brazilian freshwater fish, which is important commercially, nutritionally and ecologically. It is encountered in the Rio da Prata Bay in Southern South America. Studies on the immune system of this fish are scarce, but the physiological mechanisms of the species are analogous to those of other vertebrates. Thus, this work discusses the present study, which correlates P. lineatus leukocytes and the generation of reactive oxygen species after modulatory stimuli. Leukocytes were characterized by light and electron transmission microscopy and investigated by the generation of H2O2 and O2 ?, using phenol red, flow-cytometry and electron transmission histochemistry. The study determined that monocytes and neutrophils are the main cells responsible for generating O2 after stimulation with phorbol myristate acetate. Superoxide dismutase successfully inhibited the generation of reactive oxygen species in neutrophils and monocytes, but stimulated generation when in association with phorbol myristate acetate. Fish leukocyte samples from P. lineatus showed cross-reactivity with antibodies directed against human NADPH-oxidase antibody subunits (p47phox and p67phox). Thus, catalase enhanced the presence of p47phox. Neutrophil mitochondria were shown to be generators of H2O2 (charged by cerium precipitate), being enlarged and changing their format. The present study contributes to a better understanding of the respiratory burst pathways in this species and suggests mitochondria as the organelle responsible for generation of reactive oxygen species. 相似文献
506.
Lucélia Tessaro Cesar Pereira Rebechi de Toledo Giovano Neumann Ricardo Andrei Krause Fábio Meurer Maria Raquel Marçal Natali Robie Allan Bombardelli 《Aquaculture Research》2014,45(9):1425-1433
This study was conducted to evaluate the effects of different diet energy levels on animal performance. Specifically, this investigation examined the reproductive and histological aspects of the liver and gonads of female silver catfish (Rhamdia quelen). These fish were fed for 210 days with diets containing 30% digestible protein (DP) and digestible energy (DE) that corresponded to 11.93, 12.98, 14.03, 15.07 and 16.12 MJ of DE kg?1. The initial and final lengths, weights, and weight gains, the visceral, gonadal, and hepatosomatic indices, and the histological parameters hepatocytes area and gonadal stages were evaluated. In the reproductive season, the fish were submitted to an artificial reproduction protocol and the percentage of spawning females and their relative and absolute fecundity were evaluated. DE did not affect reproductive or animal performance aspects (P > 0.05). Cytoplasmic vacuoles in hepatocytes were observed in higher DE levels. Thus, female Rhamdia quelen can be fed a diet of 30% DP with 11.93 MJ of DE kg?1 without reproductive or performance losses. 相似文献
507.
A study was conducted in the greenhouse to determine the effects of conventional and organic nitrogen (N) fertilizer on Fusarium wilt, caused by Fusarium solani, in northern highbush blueberry (Vaccinium corymbosum L. ‘Legacy’). Root colonization by mycorrhizal fungi, soil microbial activity, and leaf antioxidants content was also measured the treatments. Plants grown with organic N fertilizer exhibited a lower incidence of Fusarium wilt than those grown with conventional N fertilizer (5% and 30% by the end of the experiment, respectively). Organic fertilizer also increased the soil biota activity, mycorrhizal colonization, and leaf antioxidant content relative to conventional N source. The results suggest that organic N fertilizer may improve the tolerance of blueberry to soil pathogens, such as F. solani. 相似文献
508.
José Marcelo Soriano Viana Ísis Fernanda de Almeida Marcos Deon Vilela de Resende Vinícius Ribeiro Faria Fabyano Fonseca e Silva 《Euphytica》2010,174(1):31-39
Best Linear Unbiased Prediction (BLUP) has become the most widely used method for genetic assessment of animal and perennial species, and it is potentially relevant for annual crops. The objective of this study was to assess this method for selection within non-inbred families in recurrent breeding programs. The ‘animal model’ was fitted. The data were expansion volume (EV) and grain yield of plants in recombination plots of two to three selection cycles in the popcorn population Viçosa, with half- and full-sib progenies. The ASReml program was used to perform the analyses. For both EV and yield the breeding values predicted from the additive and additive-dominant models were highly correlated. Multi-generation BLUP was, in general, more accurate than single-generation analysis. These two methods resulted in highly correlated predicted breeding values. The dominance genetic values predicted from the single- and multi-generation analysis were also highly correlated. The pedigree information reduced the percentage of coincidences among the selected individuals relative to phenotypic selection mainly in the population structured in half-sib families. Based on breeding values predicted by BLUP analysis, the most efficient selection procedure was mass selection. 相似文献
509.
Rafaela?Cristina?dos?Santos Maria?Fernanda?Gomes?Villalba?Pe?aflorEmail author Patrícia?Alessandra?Sanches Cristiane?Nardi José?Mauricio?Sim?es?Bento 《Phytoparasitica》2016,44(1):47-54
Insect-borne viruses promote several changes in plant phenotype, which can modify plant-vector interactions in favor of virus survival and dissemination. Although co-infections commonly occur in the field, little is known about their effects on interactions with the vector. The ecological interactions between Barley Yellow Dwarf Virus (BYDV) and its aphid vector, Rhopalosiphum padi, have been investigated extensively, but the vector’s behavior in more complex scenarios has yet to be examined. We assessed olfactory response and performance of R. padi to wheat singly and doubly infected by the pathogenic fungus Giberella zeae and BYDV. Non-viruliferous aphids preferred odors of BYDV-infected wheat over healthy wheat, as previously reported in the literature, and they were still preferentially attracted to BYDV-infected plant during co-infection. However, around 35% more non-viruliferous aphids chose healthy wheat over G. zeae-infected wheat. Viruliferous aphids did not show any preference to the treatments. BYDV-infected wheat was a superior host than healthy wheat for the aphids whose population increased in 25%. We observed a synergistic effect of the co-infected wheat, which was the best host for aphids, and promoted an elevation of 42% on population growth. Our results indicate that co-infection might be beneficial for virus spread as does not interfere with aphid olfactory preference and provides greater colony growth than in singly infected plants. 相似文献