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681.
Griselda Parés‐Sierra Eduardo Durazo Marco Antonio Ponce Daniel Badillo Gabriel Correa‐Reyes María Teresa Viana 《Aquaculture Research》2014,45(9):1459-1469
Triplicate groups of rainbow trout (Oncorhynchus mykiss) (1.4 ± 0.1 g) were fed experimental diets containing four levels of protein substitution to totally replace fishmeal with poultry by‐product meal (0, 33, 67 and 100%). Fishmeal (FM) from tuna fish by‐products and poultry by‐product meal ‘pet food grade' (PBM) were used. Diets were formulated to be isonitrogenous (43.5% crude protein) and isolipidic (12.5% crude fat). After 80 days of feeding, no significant differences were found in terms of thermal unit growth coefficient (TGC). However, the EPA levels in muscle tissue among treatments 0PBM, 24PBM and 44PBM were found to be significantly higher than those for the 59PBM diet. Nevertheless, a re‐feeding period with the control diet showed that 28 days was long enough to regain the FA profile needed. We concluded that PBM used up to 44% in diets for juvenile rainbow trout can be used without a significantly decrease in EPA and DHA under the present conditions. The use of a whole fishmeal diet could be an important strategy to recuperate the fatty acid profile obtained when trout is feed on PBM basis. It will be important to perform longer experiments with larger fish to confirm these results. 相似文献
682.
Early perception of stink bug damage in developing seeds of field‐grown soybean induces chemical defences and reduces bug attack
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683.
684.
Beak microstructure analysis as a tool to identify potential rearing stress for Octopus vulgaris paralarvae
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Rita Melo Franco‐Santos Catalina Perales‐Raya Eduardo Almansa Marleen De Troch Diego Garrido 《Aquaculture Research》2016,47(9):3001-3015
Octopus vulgaris is a viable candidate for commercial aquaculture, but rearing procedures might stress individuals and result in diminished growth and survival. This study investigated the relationship between possible stress sources (tank transposition and syphoning) when rearing O. vulgaris paralarvae and the deposition pattern of growth increments in their beak microstructure. Light intensity at the facility was heterogeneous, and accounted for with an experimental design consisting of blocks without replicates. Growth and survival were estimated and possible effects of handling were tested for both parameters. Increments and stress marks were counted in 120 paralarval upper jaws (UJ), and the number of UJs with a mark on the day of stress application (day 8) was quantified. Differences in light intensity, diet quantity and total number of marks in the UJ were also compared between treatments. Growth and survival were statistically similar between treatments, although the control treatment showed a tendency for higher survival rates. Age at first increment deposition coincided with day 1 of experiment, and a 1 increment day?1 deposition rate was validated for the experiment duration. The number of stress marks was significantly different between the control and other treatments, indicating that handling might cause stress and that marks can be used as a biomarker for stress, although the occurrence of stress marks on day 8 was not significantly different. Light intensity and diet might have also been relevant stressors and confounded the results. The results herein presented are important for improving rearing conditions for O. vulgaris paralarvae. 相似文献
685.
Adrian Muller Eduardo Aguilera Colin Skinner Andreas Gattinger 《Agriculture and Human Values》2016,33(4):943-947
A recent study by McGee (Agriculture and Human Values, 32, 255–263, 2015) from the University of Oregon has led to discussions in international media and on the web. This study addresses an interesting question and applies advanced statistics for its analysis. However, we identify several methodological flaws that invalidate the results. First, McGee tests a hypothesis that does not correspond to his main question and which does not allow McGee to derive the conclusions that are drawn in his paper and reported in the media coverage. Second, the data used are not adequate for the analysis because: i) the dependent variable does not reflect the greenhouse gas emissions characteristics of organic agriculture (e.g. different emission factors in organic and conventional agriculture or avoidance of emissions from fertilizer production), ii) the explanatory variables neglect the livestock sector, and iii) trade aspects are missing. Third, McGee fails to discuss his findings in the light of quite a substantial body of experimental, bio-physical research from the US and elsewhere. 相似文献
686.
Helton N. Souza Irene M. Cardoso José M. Fernandes Flávia C. P. Garcia Verônica R. Bonfim Alvori C. Santos Anôr F. Carvalho Eduardo S. Mendonça 《Agroforestry Systems》2010,80(1):1-16
A challenge in establishing agroforestry systems is ensuring that farmers are interested in the tree species, and are aware
of how to adequately manage these species. This challenge was tackled in the Atlantic Rainforest biome (Brazil), where a participatory
trial with agroforestry coffee systems was carried out, followed by a participatory systematisation of the farmers experiences.
Our objective was to identify the main tree species used by farmers as well as their criteria for selecting or rejecting tree
species. Furthermore, we aimed to present a specific inventory of trees of the Leguminosae family. In order to collect the
data, we reviewed the bibliography of the participatory trial, visited and interviewed the farmers and organised workshops
with them. The main farmers’ criteria for selecting tree species were compatibility with coffee, amount of biomass, production
and the labour needed for tree management. The farmers listed 85 tree species; we recorded 28 tree species of the Leguminosae
family. Most trees were either native to the biome or exotic fruit trees. In order to design and manage complex agroforestry
systems, family farmers need sufficient knowledge and autonomy, which can be reinforced when a participatory methodology is
used for developing on-farm agroforestry systems. In the case presented, the farmers learned how to manage, reclaim and conserve
their land. The diversification of production, especially with fruit, contributes to food security and to a low cost/benefit
ratio of agroforestry systems. The investigated agroforestry systems showed potential to restore the degraded landscape of
the Atlantic Rainforest biome. 相似文献
687.
Takeshi Kanaya Hisashi Kokubun Hitoshi Watanabe Goro Hashimoto Eduardo Marchesi Laura Bullrich Toshio Ando 《Scientia Horticulturae》2010
To evaluate and describe the current status of Calibrachoa cultivars as bedding plants, the seasonal flowering of 91 commercial cultivars were compared to those of natural species using principal components analysis. The predominant flowering of the cultivars, that is, floriferous in late spring to early summer with a tendency to reduce flower production toward winter, seems to have remained unchanged from that of natural species. However, properties desired in bedding plants, such as early flowering and continuous flowering under short-day and/or low temperature conditions, appear to have been improved in a considerable number of cultivars, although there is still room for improvement. Seasonal and total floral counts were higher in many cultivars compared to natural species. Several natural species were selected for their unique flowering ability and should be evaluated as gene resources for improving the flowering of Calibrachoa cultivars. 相似文献
688.
Valéria Sandra de Oliveira Costa Sami Jorge Michereff Ricardo Brainer Martins Carlos Alberto Tuão Gava Eduardo Seiti Gomide Mizubuti Marcos Paz Saraiva Câmara 《European journal of plant pathology / European Foundation for Plant Pathology》2010,127(4):509-519
The aim of the present study was to assess diversity in the Botryosphaeriaceae on trees and fruit of mango (Mangifera indica L.) in a semi-arid region in northeastern Brazil in which most exported fruit in the country are produced. Using morphological characteristics and DNA sequence data (ITS-1, ITS-2 and 5.8S rDNA) we confirmed the presence of Lasiodiplodia theobromae in the region, and for the first time report Fusicoccum aesculi and Neofusicoccum parvum. L. theobromae was prevalent in the Assú Valley and F. aesculi and N. parvum were in the São Francisco Valley. In fruit inoculations, L. theobromae and N. parvum were more virulent than F. aesculi. 相似文献
689.
Cusser Sarah Grando Carolina Zucchi Maria Imaculada López-Uribe Margarita M. Pope Nathaniel S. Ballare Kimberly Luna-Lucena Danielle Almeida Eduardo A. B. Neff John L. Young Kenneth Jha Shalene 《Landscape Ecology》2019,34(7):1825-1836
Landscape Ecology - Bees are the most important pollinators of crops worldwide. For most bees, patches of semi-natural habitat within or adjacent to crops can provide important nesting and food... 相似文献
690.
J. Alberto Gallardo-Cruz Eduardo A. Pérez-García Jorge A. Meave 《Landscape Ecology》2009,24(4):473-482
Topography strongly affects the distribution of insolation in the terrain. Patterns of incoming solar radiation affect energy
and water balances within a landscape, resulting in changes in vegetation attributes. Unlike other regions, in seasonally
dry tropical forest areas the potential contribution of topography-related environmental heterogeneity to β-diversity is unclear. In Mt. Cerro Verde (Oaxaca), S. Mexico, we: (1) modelled potential energy income for N- and S-facing
slopes based on a digital elevation model, (2) examined the response of vegetation structure to slope aspect and altitude
and (3) related variations in plant diversity to topography-related heterogeneity. Vegetation survey and modelling of potential
energy income (SOLEI-32 model) were based on 30 plots equally distributed among three altitudinal belts defined for each slope
of the mountain; combining the three altitudinal belts and the two slopes produced six environmental groups, represented by
five vegetation plots each. Potential energy income was about 20% larger on the S than on the N slope (9,735 versus 8,138 MJ/m2), but it did not vary with altitude. In addition, the temporal behaviour of potential energy income throughout the year differed
greatly between slopes. Vegetation structure did not show significant changes linked to the environmental gradients analysed,
but altitude and aspect did affect β-diversity. We argue that the classic model of slope aspect effect on vegetation needs reconsideration for tropical landscapes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorised users. 相似文献