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101.
Raissa Rachel Salustriano da Silva-Matos Gabriel Barbosa da Silva Jr Adenaelson de Souza Marques Maciel Lima Monteiro Josy Anteveli Osajima 《Archives of Agronomy and Soil Science》2016,62(3):445-455
The identification of alternative substrates suitable for seedling production is very important, while boron nutrition is also relevant due to plant requirement and its difficult management. Thus, four experiments were carried out from October 2012 to April 2013 to evaluate the effect of substrates using decomposed buriti (Mauritia vinifera Mart.) stem (DBS) and boron fertilizing for seedling production of yellow passion fruit (Passiflora edulis Sims). The experimental design was completely randomized in factorial scheme 6 × 2 + 1, referring to the substrates [S1: DBS, S2: soil and sand 1:1 (20%) + DBS (80%), S3: soil and sand 1:1 (40%) + DBS (60%), S4: soil and sand 1:1 (60%) + DBS (40%), S5: soil and sand 1:1 (80%) + DBS (20%), S6: commercial substrate (additional treatment) and S7: soil, sand and manure 1:1:2] with and without boron. The seedling emergence, emergence rate, plant height, stem diameter, root length, root volume and dry mass of roots and shoots were recorded. The substrates S2 (without B fertilizing) and S4 (B fertilized with 0.5 mg dm?3) produced seedlings with more than 3.0 g of shoot dry mass and at least 30 cm in height, and can be used for production of high-quality yellow passion fruit seedlings. 相似文献
102.
Optimizing nitrogen use efficiency in wheat and potatoes: interactions between genotypes and agronomic practices 总被引:1,自引:0,他引:1
Eleanor Y. Swain Leonidas Rempelos Caroline H. Orr Gavin Hall Rachel Chapman Mftah Almadni Elizabeth A. Stockdale Jonathan Kidd Carlo Leifert Julia M. Cooper 《Euphytica》2014,199(1-2):119-136
One approach to decrease the environmental impact of crop production and reduce costs is to optimize agronomic practices and genotypes so that nutrients are used more efficiently. In this study the effects of agronomic practices (rotations, crop protection, fertilization) on yields, nitrogen use efficiency (NUE) and associated parameters were studied in an experiment using two winter wheat genotypes (Cordiale and Scaro) in one season and two potato genotypes (Sarpo Mira and Sante) in two seasons. The wheat showed no varietal differences in yield and NUE; instead the fertilization regime was the main factor affecting yield and NUE with higher values observed when conventional fertilization was used. The exception was for wheat grown after three years grass/clover ley when there was no added yield benefit from conventional fertilization of the organically bred variety (Scaro). This demonstrates the potential for N fixing crops to provide sufficient N to high yielding cereals if grown for long enough prior to planting. The greatest gains in NUE were achieved by combining an N efficient genotype with conventional crop management in an organic rotation. Fertilization and genotypic variation were the main factors affecting potato tuber yield and NUE, with the late maturing Sarpo Mira displaying elevated yields and NUE compared with the early maturing Sante. The use of organic fertility sources resulted in lower NUE, but N release from organic sources may increase NUE of future crops. This highlights the need for long-term nutrient balance and modelling studies to assess NUE at the crop rotation scale. 相似文献
103.
Rachel E. Creamer Pat Bellamy Helaina I. J. Black Clare M. Cameron Colin D. Campbell Paul Chamberlain Jim Harris Nisha Parekh Mark Pawlett Jan Poskitt Dote Stone Karl Ritz 《Biology and Fertility of Soils》2009,45(6):623-633
The use of indicators in soil monitoring schemes to detect changes in soil quality is receiving increased attention, particularly
the application of soil biological methods. However, to date, the ability to compare information from different laboratories
applying soil microbiological techniques in broad-scale monitoring has rarely been taken into account. This study aimed to
assess the consistency and repeatability of two techniques that are being evaluated for use as microbiological indicators
of soil quality: multi-enzyme activity assay and multiple substrate-induced respiration (MSIR). Data were tested for intrinsic
(within-assay plate) variation, inter-laboratory repeatability (geometric mean regression and correlation coefficient) and
land-use discrimination (principal components analysis). Intrinsic variation was large for both assays suggesting that high
replicate numbers are required. Inter-laboratory repeatability showed diverging patterns for the enzyme assay and MSIR. Discrimination
of soils was significant for both techniques with relatively consistent patterns; however, combined laboratory discrimination
analyses for each technique showed inconsistent correspondence between the laboratories. These issues could be addressed through
the adoption of reliable analytical standards for biological methods along with adequate replication. However, until the former
is addressed, dispersed analyses are not currently advisable for monitoring schemes. 相似文献
104.
A 16-year-old Vietnamese potbellied pig was examined because of recurrent ocular discharge and reduced visual ability. Bilateral upper eyelid entropion and impaired vision secondary to periocular fat deposition were diagnosed. Surgical correction with excision of subdermal fat and redundant skin was performed to address both issues. Surgery restored vision and resolved ocular irritation. More than 1 year following surgical therapy the pig is visual and comfortable with no evidence of recurrent fat deposition or entropion. 相似文献
105.
PCR-sequence characterization of new adenoviruses found in reptiles and the first successful isolation of a lizard adenovirus 总被引:1,自引:0,他引:1
A consensus nested PCR was used to screen diagnostic samples from approximately 70 reptiles for the presence of adenoviruses (AdV) in the years 2006-2007. Classical virus isolation methods were also used with all samples. After adenoviruses were detected in a group of helodermatid lizards in a Danish zoo, a follow-up study was also carried out on lizards from this group (10 Mexican beaded lizards and 24 Gila monsters) over the period of a year. Adenoviruses were detected in a total of 26 lizards and snakes by PCR. The PCR amplicons from all positive animals were sequenced and the resulting polymerase gene sequences were used for phylogenetic analysis. Altogether six Agamid AdVs were amplified, with a minimal sequence variation between one another and between these and GenBank Agamid AdVs. The sequence obtained from one of the Gila monsters is identical with the GenBank Helodermatid AdV, while the sequences from the Mexican beaded lizards differ from this. In a snake collection we have detected a new AdV from an Asp viper. All of the above mentioned adenoviruses cluster in the Atadenovirus genus. However, the sequence from a new Varanid AdV detected in this study clusters outside this genus. On cell culture, viruses were isolated from three of the AdV positive helodermatid lizards (one Mexican beaded lizard and two Gila monsters) and identified as AdVs based on electron microscopy and PCR and sequencing using cell culture supernatant. This is the first report of the successful isolation of a lizard AdV. 相似文献
106.
Matias Bermann Daniela Lourenco Vivian Breen Rachel Hawken Fernando Brito Lopes Ignacy Misztal 《Journal of animal science》2021,99(4)
The introduction of animals from a different environment or population is a common practice in commercial livestock populations. In this study, we modeled the inclusion of a group of external birds into a local broiler chicken population for the purpose of genomic evaluations. The pedigree was composed of 242,413 birds and genotypes were available for 107,216 birds. A five-trait model that included one growth, two yield, and two efficiency traits was used for the analyses. The strategies to model the introduction of external birds were to include a fixed effect representing the origin of parents and to use unknown parent groups (UPG) or metafounders (MF). Genomic estimated breeding values (GEBV) were obtained with single-step GBLUP using the Algorithm for Proven and Young. Bias, dispersion, and accuracy of GEBV for the validation birds, that is, from the most recent generation, were computed. The bias and dispersion were estimated with the linear regression (LR) method,whereas accuracy was estimated by the LR method and predictive ability. When fixed UPG were fit without estimated inbreeding, the model did not converge. In contrast, models with fixed UPG and estimated inbreeding or random UPG converged and resulted in similar GEBV. The inclusion of an extra fixed effect in the model made the GEBV unbiased and reduced the inflation. Genomic predictions with MF were slightly biased and inflated due to the unbalanced number of observations assigned to each metafounder. When combining local and external populations, the greatest accuracy can be obtained by adding an extra fixed effect to account for the origin of parents plus UPG with estimated inbreeding or random UPG. To estimate the accuracy, the LR method is more consistent among scenarios, whereas the predictive ability greatly depends on the model specification. 相似文献
107.
Jack PJ Amos-Ritchie RN Reverter A Palacios G Quan PL Jabado O Briese T Lipkin WI Boyle DB 《Veterinary microbiology》2009,133(1-2):145-153
Definitive diagnosis of vesicular or vesicular-like lesions in livestock animals presents challenges both for veterinary clinicians and diagnostic laboratories. It is often impossible to diagnose the causative disease agent on a clinical basis alone and difficult to collect ample vesicular epithelium samples. Due to restrictions of time and sample size, once laboratory tests have ruled out foot-and-mouth disease, vesicular stomatitis and swine vesicular disease a definitive diagnosis may remain elusive. With the ability to test a small quantity of sample for a large number of pathogens simultaneously, DNA microarrays represent a potential solution to this problem. This study describes the application of a long oligonucleotide microarray assay to the identification of viruses known to cause vesicular or vesicular-like lesions in livestock animals. Eighteen virus isolates from cell culture were successfully identified to genus level, including representatives of each foot-and-mouth disease virus serotype, two species of vesicular stomatitis virus (VSV), swine vesicular disease virus, vesicular exanthema of swine virus (VESV), bovine herpesvirus 1, orf virus, pseudocowpox virus, bluetongue virus serotype 1 and bovine viral diarrhoea virus 1. VSV and VESV were also identified in vesicular epithelium samples, with varying levels of sensitivity. The results indicate that with further development this microarray assay could be a valuable tool for the diagnosis of vesicular and vesicular-like diseases. 相似文献
108.
Knowing which environmental characteristics constrain forest understory species’ distribution and reproduction can inform conservation decisions about habitat management and locations for reintroduction efforts. Differential plant performance is common in varying environmental conditions, such as levels of canopy closure. Actaea elata (tall bugbane) is a rare, perennial, forest understory herb found from Oregon to British Columbia. Populations throughout this species’ range commonly occur in managed forests. We assessed the importance of environmental variation on the distribution and flowering of A. elata at both microhabitat and site-level scales. At four sites encompassing a variety of forest types, we measured several biotic and abiotic variables at vegetative and reproductive plants, as well as at random points. We measured these same variables at three sites where A. elata has been extirpated. Within occupied sites, reproductive plants were more likely to be located in canopy gaps than were vegetative plants. Both vegetative and reproductive plants were more likely to be found in areas of high herb cover compared to random points. These results indicate that gaps in the canopy may be critical for this species’ ability to reproduce, but survival may be possible in a broader range of forest understory conditions (similar to other co-occurring herb species). Random points at extirpated and occupied sites both tended to be located in areas of lower canopy openness and moisture availability than points in occupied sites where A. elata was present. Extirpated sites were either densely forested or clearcut, while occupied sites contained stands of intermediate density. Circaea alpina, Geranium robertianum, and Lactuca muralis were indicator species for A. elata and normally indicate moist soils, with Circaea alpina being a strong indicator of the presence of flowering A. elata. Taken together, our results suggest that maintenance of canopy gaps is important to promote flowering, and understory species that indicate moist sites, particularly Circaea alpina, can be used as aids to locate new populations of A. elata. 相似文献
109.
Mastrodi Salgado J Baroni Ferreira TR de Oliveira Biazotto F Dos Santos Dias CT 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):39-43
Antioxidants are compounds responsible for free radical scavenging in the body. They protect the organism from oxidative modification
of cells and tissues. These modifications have been associated with degenerative diseases, atherosclerosis and carcinogenesis.
Punica granatum displays high antioxidant potential due to the presence of phenolic compounds, which are capable of disease prevention. The
present study showed the highest antioxidant activity in pomegranate peel than in seeds and pulp. Based on these results,
pomegranate peel was used to produce dried extract that was added to commercial tomato juice and orange juice with strawberries.
Analysis to determine the content of phenolic compounds and antioxidant activity was performed on pomegranate pulp, seeds
and peel and in juices enriched with dried extract of pomegranate peel. The dried extract was responsible for a significant
increase in antioxidant activity of the juices, proportional to the concentrations added. However, although both flavors of
enriched juices displayed high antioxidant levels, the samples with higher dried extract concentrations received the lowest
scores from sensory analysis participants due to the characteristic astringent flavor of pomegranate peels. Therefore, to
obtain greater acceptance in the consumer market, we concluded that the maximum addition of dried pomegranate peel extract
is 0.5% in tomato juice and orange juice with strawberries. 相似文献
110.
Valerie J. Stull Mukata Wamulume Mwangala I. Mwalukanga Alisad Banda Rachel S. Bergmans Michael M. Bell 《Agriculture and Human Values》2018,35(4):867-883
Entomophagy—the practice of eating insects—has been touted as a means to combat undernutrition and food insecurity globally. Insects offer a nutritious, environmentally friendly alternative to resource-intensive livestock. But the benefits of edible insects cannot be realized if people do not choose to eat them. We therefore examine the social acceptability of edible insects in rural Zambia, where entomophagy is common but underexplored. Through a village case study, we show that edible insects are not valued equally, are understood socially, and seem to reflect and reinforce social values. We utilize grounded theory and ethnographic methods, including semi-structured interviews, focus groups, and observation to examine collective entomophagy beliefs. While we expected to see differentiation in perceptions across groups based on kinship, we demonstrate that social values related to class, urbanism, gender, and age emerge as more germane explanations for entomophagy perceptions, reflecting their social weight. By expanding on current apperception of entomophagy behavior, our findings inform future research and efforts to promote entomophagy through minilivestock farming. Systems designed to maximize output, minimize labor, and highlight benefits are more likely to be widely accepted. We do not anticipate tribal association will be the primary limitation on minilivestock adoption in this context. 相似文献