Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 274
Filtrar
1.
J Sci Food Agric ; 104(1): 235-248, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37596244

RESUMO

BACKGROUND: Recently, vesicles derived from plant cell membranes have received attention for their potential use as active biomolecules and nanocarriers, and obtaining them from organic crops may be an interesting option because different farming systems can affect production, plant secondary metabolism and biochemistry of cell membranes. The present study aimed to determine how organic and conventional farming affects the mineral nutrition, gas exchange, CO2 fixation and biochemical composition of lemon fruits, which could have an impact on the different fractions of cell membranes in pulp and juice. RESULTS: Organic trees had higher intrinsic water use efficiency (WUEi) but conventional trees had higher stomatal conductance (gs) and nitrogen use efficiency (NUtE). Also, organic lemons had significantly higher levels of some micronutrients (Ca, Cu, Fe and Zn). Second, the main differences in the membrane vesicles showed that organic pulp vesicles had a higher antioxidant activity and more oleic acid, whereas both types of vesicles from conventional lemons had more linoleic acid. CONCLUSION: In conclusion, organic farming did not alter carbon fixation parameters but impacted nitrogen fixation and water uptake, and resulted in higher micronutrient levels in lemons. These mineral nutritional changes could be related to the higher production of membranes that showed suitable morphological traits and a high antioxidant activity, positively correlated with a high amount of oleic acid, which could have stronger cell protection characteristics. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Citrus , Agricultura Orgânica , Agricultura Orgânica/métodos , Citrus/química , Frutas/química , Antioxidantes/análise , Ácido Oleico/análise , Agricultura/métodos , Minerais/análise , Água/análise
2.
Microb Ecol ; 86(3): 2047-2059, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37010558

RESUMO

Soil microbial communities are key players responsible for imparting suppressive potential to the soil against soil-borne phytopathogens. Fungi have an immense potential to inhibit soil-borne phytopathogens, but the fungal counterpart has been less explored in this context. We assessed the composition of fungal communities in soil under long-term organic and conventional farming practice, and control soil. The disease-suppressive potential of organic field was already established. A comparative analysis of the disease suppressiveness contributed by the fungal component of soil from conventional and organic farms was assessed using dual culture assays. The quantification of biocontrol markers and total fungi was done; the characterization of fungal community was carried out using ITS-based amplicon sequencing. Soil from organic field exhibited higher disease-suppressive potential than that from conventional farming, against the pathogens selected for the study. Higher levels of hydrolytic enzymes such as chitinase and cellulase, and siderophore production were observed in soil from the organic field compared to the conventional field. Differences in community composition were observed under conventional and organic farming, with soil from organic field exhibiting specific enrichment of key biocontrol fungal genera. The fungal alpha diversity was lower in soil from the organic field compared to the conventional field. Our results highlight the role of fungi in contributing to general disease-suppressive ability of the soil against phytopathogens. The identification of fungal taxa specifically associated with organic farming can aid in understanding the mechanism of disease suppression under such a practice, and can be exploited to induce general disease suppressiveness in otherwise conducive soil.


Assuntos
Fungos , Solo , Fungos/genética , Bactérias , Agricultura/métodos , Agricultura Orgânica/métodos , Microbiologia do Solo
3.
J Environ Manage ; 324: 116414, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36352718

RESUMO

The potential link between certified organic farming and biodiversity and conservation remains unexplored in Australia, despite the country having the world's largest amount of certified organic farmland and unprecedented biodiversity loss. This study modelled the spatial effects of organic farming (intensity of local farming systems), environmental heterogeneity, and urbanisation on two widely studied environmental taxa - vascular plant and bird species richness (surrogate measures of biodiversity) - in South Australia, using a unique certified organic farming postcode level dataset from 2001 to 2016 (N = 5440). The spatial Durbin error model results confirmed the positive spatial congruence of organic farming with greater vascular plant species richness, whereas only weak to no significant evidence was found for bird species richness. Landscape features (habitat heterogeneity) and green vegetation (a proxy indicator of resource availability) - rather than organic farming - appeared to be most associated with bird species richness. Both plant and bird species richness were positively associated with habitat heterogeneity (land cover diversity and elevation range), plant productivity and proportion of conservation land and water bodies. Whereas, increased anthropogenic land use for cropping and horticultural farming, soil type diversity and proximity to the coast significantly reduced species richness of both taxa. The results suggest that a multi-scale spatially refined biodiversity conservation strategy, with spatial targeting that promotes low intensive farming systems and increases landscape heterogeneity to provide quality habitat (a whole of landscape approach by incorporating private agricultural landholders), could be beneficial for biodiversity conservation.


Assuntos
Biodiversidade , Agricultura Orgânica , Animais , Austrália , Aves/classificação , Ecossistema , Agricultura Orgânica/métodos , Austrália do Sul , Conservação dos Recursos Naturais
4.
Mol Ecol ; 31(15): 4017-4030, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35726521

RESUMO

It is generally assumed that the dependence of conventional agriculture on artificial fertilizers and pesticides strongly impacts the environment, while organic agriculture relying more on microbial functioning may mitigate these impacts. However, it is not well known how microbial diversity and community composition change in conventionally managed farmers' fields that are converted to organic management. Here, we sequenced bacterial and fungal communities of 34 organic fields on sand and marine clay soils in a time series (chronosequence) covering 25 years of conversion. Nearby conventional fields were used as references. We found that community composition of bacteria and fungi differed between organic and conventionally managed fields. In the organic fields, fungal diversity increased with time since conversion. However, this effect disappeared when the conventional paired fields were included. There was a relationship between pH and soil organic matter content and the diversity and community composition of bacteria and fungi. In marine clay soils, when time since organic management increased, fungal communities in organic fields became more dissimilar to those in conventional fields. We conclude that conversion to organic management in these Dutch farmers' fields did not increase microbial community diversity. Instead, we observed that in organic fields in marine clay when time since conversion increased soil fungal community composition became progressively dissimilar from that in conventional fields. Our results also showed that the paired sampling approach of organic and conventional fields was essential in order to control for environmental variation that was otherwise unaccounted for.


Assuntos
Agricultura Orgânica , Solo , Agricultura/métodos , Bactérias/genética , Argila , Fungos/genética , Agricultura Orgânica/métodos , Solo/química , Microbiologia do Solo
5.
Ecol Lett ; 25(7): 1699-1710, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35545523

RESUMO

Organic farming supports higher biodiversity than conventional farming, but at the cost of lower yields. We conducted a meta-analysis quantifying the trade-off between biodiversity and yield, comparing conventional and organic farming. We developed a compatibility index to assess whether biodiversity gains from organic farming exceed yield losses, and a substitution index to assess whether organic farming would increase biodiversity in an area if maintaining total production under organic farming would require cultivating more land at the expense of nature. Overall, organic farming had 23% gain in biodiversity with a similar cost of yield decline. Biodiversity gain is negatively correlated to yield loss for microbes and plants, but no correlation was found for other taxa. The biodiversity and yield trade-off varies under different contexts of organic farming. The overall compatibility index value was close to zero, with negative values for cereal crops, positive for non-cereal crops, and varies across taxa. Our results indicate that, on average, the proportion of biodiversity gain is similar to the proportion of yield loss for paired field studies. For some taxa in non-cereal crops, switching to organic farming can lead to a biodiversity gain without yield loss. We calculated the overall value of substitution index and further discussed the application of this index to evaluate when the biodiversity of less intensified farming system is advantageous.


Assuntos
Biodiversidade , Agricultura Orgânica , Agricultura/métodos , Produtos Agrícolas , Agricultura Orgânica/métodos
6.
Ecol Appl ; 32(4): e2576, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35191107

RESUMO

Biodiversity-benefits of organic farming have mostly been documented at the field scale. However, these benefits from organic farming to species diversity may not propagate to larger scales because variation in the management of different crop types and seminatural habitats in conventional farms might allow species to cope with intensive crop management. We studied flowering plant communities using a spatially replicated design in different habitats (cereal, ley and seminatural grasslands) in organic and conventional farms, distributed along a gradient in proportion of seminatural grasslands. We developed a novel method to compare the rates of species turnover within and between habitats, and between the total species pools in the two farming systems. We found that the intrahabitat species turnover did not differ between organic and conventional farms, but that organic farms had a significantly higher interhabitat turnover of flowering plant species compared with conventional ones. This was mainly driven by herbicide-sensitive species in cereal fields in organic farms, as these contained 2.5 times more species exclusive to cereal fields compared with conventional farms. The farm-scale species richness of flowering plants was higher in organic compared with conventional farms, but only in simple landscapes. At the interfarm level, we found that 36% of species were shared between the two farming systems, 37% were specific to organic farms whereas 27% were specific to conventional ones. Therefore, our results suggest that that both community nestedness and species turnover drive changes in species composition between the two farming systems. These large-scale shifts in species composition were driven by both species-specific herbicide and nitrogen sensitivity of plants. Our study demonstrates that organic farming should foster a diversity of flowering plant species from local to landscape scales, by promoting unique sets of arable-adapted species that are scarce in conventional systems. In terms of biodiversity conservation, our results call for promoting organic farming over large spatial extents, especially in simple landscapes, where such transitions would benefit plant diversity most.


Assuntos
Herbicidas , Agricultura Orgânica , Agricultura/métodos , Biodiversidade , Ecossistema , Agricultura Orgânica/métodos , Plantas
7.
PLoS One ; 16(12): e0261133, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34890443

RESUMO

Improvement in living standards has led to the development and utilization of forest green foods. The study seeks to examine the foundation and potential of forest green food industry in Yunnan Province. By constructing the industrial competitive advantage model, this paper measured and analyzed the competitiveness of forest green food industry in Yunnan Province from 2016 to 2020 by using fuzzy evaluation method and AHP. The conclusions were as follows: (1) The competitiveness of forest green food industry in Yunnan Province was at a medium level with competitiveness index of 83.98. (2) The competitive advantage of forest green food industry in Yunnan Province mainly depended on key factors such as natural endowment and education level. The area is however not having comparative advantage in general factors and important factors. Therefore, there is the need to put in place measures to realise the full potential of forest green food industry in the area by providing players in the sector with requisite skills.


Assuntos
Alimentos Orgânicos , Agricultura Orgânica/métodos , China , Conservação dos Recursos Naturais , Desenvolvimento Econômico , Florestas , Humanos
8.
Int J Biol Macromol ; 192: 611-617, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606790

RESUMO

Mulching has been extensively sought after in modern agriculture. However, massive utilization of plastics for mulching has induced severe environmental concerns. Developing biodegradable mulch thus represents an emerging need for future agriculture. By using bamboo-derived carboxymethyl cellulose (CMC), this study proposed a crosslinking strategy to prepare liquid film as quality mulch. CMC was synthesized by delignifying bamboo and etherifying resultant cellulose, which was then blended with polyvinyl alcohol (PVA) and crosslinked by glutaraldehyde to prepare a liquid film. By simply spraying on soil, mulch can quickly form on soil surface. Especially, bamboo-timber derived mulch had strong mechanical property (18.2 MPa), good transmittance (74.2%) and moisture absorption (141%), and excellent soil moisture retention. More importantly, about 64% of used mulches were biodegraded within 60-d after burring in soil, which will not need post-handling. These results highlighted that bamboo-derived mulch can be an alternative of current plastic mulch to tackle associated environmental pollution.


Assuntos
Biodegradação Ambiental , Carboximetilcelulose Sódica/química , Agricultura Orgânica , Sasa/química , Biopolímeros , Fenômenos Químicos , Agricultura Orgânica/métodos , Compostos Fitoquímicos/química , Solo/química , Água
9.
ScientificWorldJournal ; 2021: 9970957, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34512205

RESUMO

In developed countries, the ideas of ecological agricultural production, continuous cycle, and waste-free production technologies have gained popularity. The effect from the production and consumption of ecological agricultural products is determined by the least harm to the environment, increasing the competitiveness of products, and receiving additional profit from increasing prices for higher quality products. The production of organically safe products is based on the principle of biologization, i.e., the widespread use of biological preparations, a high proportion of legumes (sources of nitrogen), and avoiding chemical plant protection products, transgenic plants, and genetically modified organisms (GMOs). This study aims to increase the productivity of safflower and improve the physicochemical and biological indicators of dark chestnut soils through the use of biologized technologies in the organic farming system. Standard methods for assessment and statistical analysis of physical and chemical parameters of soils were carried out in zone 1 of West Kazakhstan. This made it possible to identify the most optimal technology for the cultivation of safflower. The study results showed that under the influence of the phytomeliorative action of safflower in the 0-20 cm layer of dark chestnut soils, one could note an increase in the content of nitrate nitrogen by 5.95%, an increase in the content of mobile phosphorus by 5.22%, and soil loosening by 0.010 g/cm3, with the structure of the soil being 64.43%. Strong biological activity of the soil was established by the crops of safflower. The highest yield of safflower oil about 0.23 t/ha with an oil content of 30.1% was obtained using the biologized technology option. The use of biological technology, along with biological yields, increases oil yield by 0.06 t/ha or 28.06%.


Assuntos
Agricultura Orgânica/métodos , Solo , Carthamus tinctorius/crescimento & desenvolvimento , Produtos Agrícolas/crescimento & desenvolvimento , Biomarcadores Ambientais , Fertilizantes/análise , Fungicidas Industriais , Cazaquistão , Nitrogênio/análise , Óleos/análise , Fósforo/análise , Plantas Daninhas , Óleo de Cártamo , Estações do Ano , Silagem , Solo/química , Poluentes do Solo/análise
10.
Food Microbiol ; 99: 103798, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119093

RESUMO

Toxoplasma gondii infection can result in toxoplasmosis and potential psychological effects. Research commonly focuses on infection through contact with cat fecal matter or consumption of contaminated meat. However, T. gondii oocysts can persist in the environment for years and may be present in soils and on soil-grown produce. Rates of oocyst DNA recovery from produce were high, with 18% of vegetable samples testing positive for T. gondii via PCR test and melt curve analysis. Radishes had significantly higher oocyst counts than arugula, collard greens, kale, lettuce, and spinach. There were no significant differences in oocyst detection rates between samples taken from organic farmer's markets and conventional grocery stores. This study demonstrates that these oocysts can transfer to produce grown both conventionally and using organic techniques.


Assuntos
Agricultura/métodos , Contaminação de Alimentos/análise , Toxoplasma/isolamento & purificação , Verduras/parasitologia , Alimentos Orgânicos/parasitologia , Oocistos/classificação , Oocistos/genética , Oocistos/isolamento & purificação , Agricultura Orgânica/métodos , Solo/parasitologia , Toxoplasma/classificação , Toxoplasma/genética , Verduras/crescimento & desenvolvimento
11.
J Insect Sci ; 21(3)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33964162

RESUMO

Semi-natural field borders are frequently used in midwestern U.S. sustainable agriculture. These habitats are meant to help diversify otherwise monocultural landscapes and provision them with ecosystem services, including biological control. Predatory and parasitic arthropods (i.e., potential natural enemies) often flourish in these habitats and may move into crops to help control pests. However, detailed information on the capacity of semi-natural field borders for providing overwintering refuge for these arthropods is poorly understood. In this study, we used soil emergence tents to characterize potential natural enemy communities (i.e., predacious beetles, wasps, spiders, and other arthropods) overwintering in cultivated organic crop fields and adjacent field borders. We found a greater abundance, species richness, and unique community composition of predatory and parasitic arthropods in field borders compared to arable crop fields, which were generally poorly suited as overwintering habitat. Furthermore, potential natural enemies tended to be positively associated with forb cover and negatively associated with grass cover, suggesting that grassy field borders with less forb cover are less well-suited as winter refugia. These results demonstrate that semi-natural habitats like field borders may act as a source for many natural enemies on a year-to-year basis and are important for conserving arthropod diversity in agricultural landscapes.


Assuntos
Biodiversidade , Produtos Agrícolas , Agricultura Orgânica/métodos , Animais , Artrópodes , Agentes de Controle Biológico , Besouros , Ecossistema , Parasitos , Comportamento Predatório , Refúgio de Vida Selvagem , Estações do Ano , Aranhas , Vespas
12.
Foodborne Pathog Dis ; 18(8): 567-573, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33794668

RESUMO

Antimicrobial resistance (AMR) is a recognized global public health concern. Although the link between antimicrobial usage in food animals and AMR in humans is established, the detailed interactions are unclear. Antimicrobial stewardship (AMS) in livestock was first implemented in Europe with Sweden as the pioneer in 1986. Despite this head start, AMR is still an ongoing challenge for Europe. The European Union (EU) is an established agriculture producer, the second largest pork producer globally, and one of the largest markets for organic food. China is the global leader in both production and consumption of pork. China's rise in prosperity has led to an increase in its pork demand. Chinese producers commonly use antimicrobials during production for disease treatment and prevention to meet this increased demand. China's rising prosperity together with recent publicized food safety scandals, disease outbreaks in domestic livestock products, and increased AMR awareness have resulted in an increased willingness to pay and demand for organic food by Chinese consumers. Responding to the growing concerns of AMR by consumers and the World Health Organization (WHO), the Chinese government introduced a national pilot program in 2016 to reduce unnecessary antimicrobial use. Compared with China, the EU is a different entity as it is a political union comprising diverse countries and although it may have more experience in AMS, both entities face similar issues with AMR and increasing demand for organic food. Increased interest in organic food has arisen due to concerns about AMR, food safety, outbreaks of bacterial food contamination, and animal welfare. This article aims to compare the different AMS strategies employed by each entity, China and the EU, and how the increased demand for organic produce globally also influences the effort to reduce antimicrobial use in these entities' pork industries.


Assuntos
Gestão de Antimicrobianos/métodos , Microbiologia de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Agricultura Orgânica/métodos , Carne de Porco/microbiologia , Criação de Animais Domésticos/legislação & jurisprudência , Criação de Animais Domésticos/métodos , Animais , Gestão de Antimicrobianos/legislação & jurisprudência , China , Resistência Microbiana a Medicamentos , Europa (Continente) , União Europeia , Microbiologia de Alimentos/legislação & jurisprudência , Alimentos Orgânicos/microbiologia , Humanos , Gado/microbiologia , Avaliação de Programas e Projetos de Saúde , Suínos/microbiologia
13.
Ann Agric Environ Med ; 28(1): 44-48, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33775066

RESUMO

INTRODUCTION AND OBJECTIVE: Deoxynivalenol (DON, vomitoxin) and Zearalenone (ZEA) are mycotoxin contaminants of cereals and cereal products that pose a significant threat to food safety. The aim of the study was to investigate the occurrence of DON and ZEA in different organic and conventional unprocessed cereals and cereal products that are available on the Polish agricultural fields and market. A total of 78 unprocessed cereal and cereal product samples of organic and conventional production were sampled from agricultural fields situated in western Poland and from available on the Polish market packaged comercial products produced by different domestic manufacturers. All samples were analyzed for DON and ZEA by HPLC with fluorescence detection (HPLC-FLD). RESULTS: Results. Co-occurrence of DON was detected in cereals from the organic production system, the average content was 285.25 ± 134,04 µg kg -1 and from the conventional system - 373.71 ± 171,20 µg kg -1 , In flour from organic farming, the average DON content was 213.80 ± 151,28 µg kg -1, in conventional flour the average was 336.29 ± 188,90 µg kg -1. The range of DON concentrations in samples of cereal products from organic and conventional farms was detected in 26.3% and 31.6%, whereas the average concentrations of DON in cereal products was 199.60 ± 149.82 µg kg -1 and 387.67 ± 250.24 µg kg -1, respectively. CONCLUSIONS: Mycotoxins contamination seen in organic cereals and cereal products does not statistical differ from that witnessed in their conventional counterparts.


Assuntos
Agricultura/métodos , Grão Comestível/química , Grão Comestível/crescimento & desenvolvimento , Contaminação de Alimentos/análise , Alimentos Orgânicos/análise , Tricotecenos/análise , Zearalenona/análise , Farinha/análise , Agricultura Orgânica/métodos , Polônia , Triticum/química , Triticum/crescimento & desenvolvimento
14.
Microbiol Res ; 245: 126672, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33418398

RESUMO

Plant biostimulants (PBs) are an eco-friendly alternative to chemical fertilisers because of their minimal or null impact on human health and environment, while ensuring optimal nutrient uptake and increase of crop yield, quality and tolerance to abiotic stress. Although there is an increasing interest on microbial biostimulants, the optimal procedure to select and develop them as commercial products is still not well defined. This work proposes and validates a procedure to select the best plant growth promoting rhizobacteria (PGPR) as potential active ingredients of commercial PBs. The stepwise screening strategy was designed based on literature analysis and consists of six steps: (i) determination of the target crop and commercial strategy, (ii) selection of growth media for the isolation of microbial candidates, (iii) screening for traits giving major agronomical advantages, (iv) screening for traits related to product development, (v) characterisation of the mode of action of PGPR and (vi) assessment of plant growth efficacy. The strategy was validated using a case study: PGPR combined with humic acids to be applied on tomato plants. Among 200 bacterial strains isolated from tomato rhizosphere, 39 % were able to grow in presence of humic acids and shared the ability to solubilise phosphate. After the screening for traits related to product development, only 6 % of initial bacterial strains were sharing traits suitable for the further development as potential PBs. In fact, the selected bacterial strains were able to produce high cell mass and tolerated drought, aspects important for the mass production and formulation. These bacterial strains were not able to produce antibiotics, establish pathogenic interaction with plants and did not belong to bacterial species associated to human, animal and plant diseases. Most importantly, five of the selected bacterial strains were able to promote tomato seedling vigour in experiments carried out in vitro. These bacterial strains were furtherly characterised for their ability to colonize effectively tomato plant roots, produce phytohormones and solubilise soil minerals. This characterisation led to the selection of two candidates that showed the ability to promote tomato plant growth in experiments carried out in greenhouse conditions. Overall, this work provides a flow diagram for the selection of PGPR candidates to be successfully developed and commercialized as PBs. The validation of the flow diagram led to the selection of two bacterial strains belonging to Pantoea and Pseudomonas genera, potential active ingredients of new commercial PBs.


Assuntos
Bactérias/isolamento & purificação , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , Rizosfera , Bactérias/genética , Agricultura Orgânica/métodos , Doenças das Plantas , Reguladores de Crescimento de Plantas , Microbiologia do Solo
15.
Food Chem ; 342: 128379, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33097333

RESUMO

Shanghai city has encountered possible food fraud regarding the geographical mislabeling of vegetables for economic gain. A combination of δ13C, δ15N, δ2H and δ18O values and partial least squares discrimination analysis and support vector machine (SVM) methods were used for the first time to assess farming methods and determine the origin of vegetables from Shanghai city, Anhui and Zhejiang provinces. The results showed that 65.8% of Shanghai vegetables, 38.2% of Anhui vegetables and 23.6% of Zhejiang vegetables appeared to be grown using green or organic farming methods. The optimal discriminant model was obtained using SVM with a predictive accuracy of 100% for Shanghai vegetables. Zhejiang vegetables had a predictive accuracy of 91.7%, while it was difficult to distinguish Anhui vegetables from Shanghai or Zhejiang vegetables. Therefore, this study provided a useful method to identify vegetable farming methods and discriminate vegetables from Shanghai and Zhejiang.


Assuntos
Agricultura Orgânica/métodos , Verduras/química , Isótopos de Carbono/análise , China , Análise Discriminante , Espectrometria de Massas , Isótopos de Nitrogênio/análise , Isótopos de Oxigênio/análise , Máquina de Vetores de Suporte , Verduras/metabolismo
16.
Nutrients ; 12(10)2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32998302

RESUMO

Food choices affect the isotopic composition of the body with each food item leaving its distinct isotopic imprint. The common view is that the natural abundance of the stable isotopes of nitrogen (expressed as δ15N) is higher in animals than in plants that constitute our contemporary diets. Higher δ15N is thus increasingly viewed as a biomarker for meat and fish intake. Here we show that organic compared to conventional farming increases plant δ15N to an extent that can appreciably impact the performance of δ15N as a biomarker. The error that can arise when organic plants are consumed was modelled for the entire range of proportions of plant versus animal protein intake, and accounting for various intakes of organic and conventionally grown crops. This mass balance model allows the interpretation of differences in δ15N in light of organic food consumption. Our approach shows that the relationship between δ15N and meat and fish intake is highly contextual and susceptible to variation at the population, community or group level. We recommend that fertilization practices and organic plant consumption must not be overlooked when using δ15N as a biomarker for meat and fish intake or to assess compliance to nutritional interventions.


Assuntos
Proteínas Animais da Dieta/análise , Ingestão de Alimentos/fisiologia , Alimentos Orgânicos/análise , Isótopos de Nitrogênio/sangue , Proteínas de Vegetais Comestíveis/análise , Biomarcadores/sangue , Humanos , Carne/análise , Agricultura Orgânica/métodos , Plantas Comestíveis/química , Alimentos Marinhos/análise
17.
PLoS One ; 15(8): e0236574, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790770

RESUMO

Management practices such as tillage, crop rotation, irrigation, organic and inorganic inputs application are known to influence diversity and function of soil microbial populations. In this study, we investigated the effect of conventional versus organic farming systems at low and high input levels on structure and diversity of prokaryotic microbial communities. Soil samples were collected from the ongoing long-term farming system comparison trials established in 2007 at Chuka and Thika in Kenya. Physicochemical parameters for each sample were analyzed. Total DNA and RNA amplicons of variable region (V4-V7) of the 16S rRNA gene were generated on an Illumina platform using the manufacturer's instructions. Diversity indices and statistical analysis were done using QIIME2 and R packages, respectively. A total of 29,778,886 high quality reads were obtained and assigned to 16,176 OTUs at 97% genetic distance across both 16S rDNA and 16S rRNA cDNA datasets. The results pointed out a histrionic difference in OTUs based on 16S rDNA and 16S rRNA cDNA. Precisely, while 16S rDNA clustered by site, 16S rRNA cDNA clustered by farming systems. In both sites and systems, dominant phylotypes were affiliated to phylum Actinobacteria, Proteobacteria and Acidobacteria. Conventional farming systems showed a higher species richness and diversity compared to organic farming systems, whilst 16S rRNA cDNA datasets were similar. Physiochemical factors were associated differently depending on rRNA and rDNA. Soil pH, electrical conductivity, organic carbon, nitrogen, potassium, aluminium, zinc, iron, boron and micro-aggregates showed a significant influence on the observed microbial diversity. The observed higher species diversity in the conventional farming systems can be attributed to the integration of synthetic and organic agricultural inputs. These results show that the type of inputs used in a farming system not only affect the soil chemistry but also the microbial population dynamics and eventually the functional roles of these microbes.


Assuntos
Agricultura/métodos , Microbiologia do Solo , Acidobacteria/genética , Acidobacteria/isolamento & purificação , DNA Bacteriano/genética , Quênia , Microbiota , Agricultura Orgânica/métodos , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/genética
18.
Acta Sci Pol Technol Aliment ; 19(2): 159-167, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32600012

RESUMO

BACKGROUND: The chicken egg is a food product with a rich content of nutrients, such as proteins, vitamins, lipids, and minerals with high bioavailability. Furthermore, eggs are easy to prepare and a relatively inexpensive component of the human diet. The aim of this study was to compare the quality of eggs from an organic and a conventional farm and their content of Na and K. METHODS: The research material consisted of eggs from laying hens reared in two different systems - organic (according to standards for organic farming and with access to a chicken run) and cage. Forty eggs from each group were analysed. Egg quality traits were divided into destructive and non-destructive. In addition, potassium (K) and sodium (Na) contents were determined in the whole egg, yolk and albumen. RESULTS: The research results indicated slightly better quality of eggs from organic farming compared to eggs from cages in the case of most physical properties. The data clearly show that the content of sodium and potassium in the albumen, yolk and whole egg was higher in the eggs of chickens raised organically compared to the eggs of chickens reared in cages (P ≤ 0.05). CONCLUSIONS: The research results indicate a slightly better quality of eggs from the organic farm compared to eggs from cages in the case of most physical properties, as well as the content of macro-elements. Eggs in both systems are produced following scientific management practices. There are many myths among consumers regarding the nutritional quality of eggs produced in different systems. This information can be useful for raising awareness among consumers selecting eggs.


Assuntos
Criação de Animais Domésticos/métodos , Ovos/análise , Alimentos Orgânicos/análise , Valor Nutritivo , Agricultura Orgânica/métodos , Potássio/análise , Sódio/análise , Albuminas , Ração Animal , Animais , Galinhas , Comércio , Dieta , Casca de Ovo , Gema de Ovo , Ovos/normas , Feminino , Alimentos Orgânicos/normas , Humanos
19.
Nat Plants ; 6(5): 483-491, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32415295

RESUMO

Reduced insect pest populations found on long-term organic farms have mostly been attributed to increased biodiversity and abundance of beneficial predators, as well as to changes in plant nutrient content. However, the role of plant resistance has largely been ignored. Here, we determine whether host plant resistance mediates decreased pest populations in organic systems and identify potential underpinning mechanisms. We demonstrate that fewer numbers of leafhoppers (Circulifer tenellus) settle on tomatoes (Solanum lycopersicum) grown using organic management as compared to conventional. We present multiple lines of evidence, including rhizosphere soil microbiome sequencing, chemical analysis and transgenic approaches, to demonstrate that changes in leafhopper settling between organically and conventionally grown tomatoes are dependent on salicylic acid accumulation in plants and mediated by rhizosphere microbial communities. These results suggest that organically managed soils and microbial communities may play an unappreciated role in reducing plant attractiveness to pests by increasing plant resistance.


Assuntos
Agricultura Orgânica , Controle Biológico de Vetores , Defesa das Plantas contra Herbivoria , Animais , Hemípteros , Solanum lycopersicum/fisiologia , Agricultura Orgânica/métodos , Rizosfera , Microbiologia do Solo
20.
Life Sci Soc Policy ; 16(1): 3, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32390089

RESUMO

The conventional production model based on extensive use of chemical inputs such as pesticides is increasingly challenged. Organic agriculture is considered as one of the most important alternative agricultural systems to produce healthy food without any chemicals. Current models are not suitable for prediction of environmental behaviors. The current study aims to analyze the diffusion of organic agriculture to produce healthy food with the environmental sociology approach among farmers. The study was conducted using the survey research and multi-stage random sampling in Fars province, in the south of Iran. The samples included 215 farmers. The reliability of the questionnaire was confirmed by conducting a pilot study out of the main sample. The results showed that the farmers have strong attitude to the environment and are for the most part, highly intentioned to perform organic activities. Based on the results, the farmers' intention toward adoption of organic agriculture, environmental identity, and responsibility of pro-environmental behavior, and their moral norms play an important role to accept organic agricultural activities. There are also some effective factors in implementation of organic agriculture including farmers` increasing awareness about the principles of organic farming, controllability of environmental behaviors as well as their accessibility to the resources and facilities for organic farming. The study emphasized that the attitude and enhancing the knowledge do not lead to pro-environmental behaviors and organic activities directly. Using the models and environmental sociology theories is more efficient to explain pro-environmental behaviors. To this aim, some suggestions were presented to increase the adoption of organic activities and persuade the Iranian farmers to select this kind of cultivation.


Assuntos
Meio Ambiente , Fazendeiros/psicologia , Agricultura Orgânica/métodos , Agricultura/métodos , Atitude , Humanos , Irã (Geográfico) , Teoria Psicológica , Responsabilidade Social , Fatores Socioeconômicos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA