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1.
Toxins (Basel) ; 14(2)2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35202102

RESUMO

The levels of deoxynivalenol (DON)-a mycotoxin produced by Fusarium graminearum-in maize for food and feed are subject to European Union regulations. Obtaining a compliant harvest requires the identification of agronomic and climatic risk factors related to higher fungal contamination and DON production. A national, multiyear database for maize was created, based on field survey data collected from 2004 to 2020. This database contains information about agricultural practices, climatic sequences and DON content at harvest for a total of 2032 maize fields localized in the French maize-growing regions. A linear mixed-model approach highlighted the presence of borers, late harvest and inadequate crop residue management, normal-to-cold temperatures in March, humidity in August and the absence of a hot end of the maize development cycle with a dry August as creating conditions favoring maize contamination with DON. The various possible associations between these risky climatic conditions and agricultural practices were compared, grouped and ranked as related to very low to high DON concentrations. Some combinations may even exceed the regulatory threshold. The national prevention tool, created for producers and agricultural cooperatives, is informative and easy-to-use to control the sanitary quality of their harvest.


Assuntos
Agricultura/métodos , Contaminação de Alimentos , Tricotecenos/química , Tempo (Meteorologia) , Zea mays/química , União Europeia , França , Fusarium/metabolismo , Fatores de Risco , Tricotecenos/metabolismo
2.
Toxins (Basel) ; 13(3)2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809408

RESUMO

The levels of fumonisins (FUMO)-mycotoxins produced by Fusarium verticillioides-in maize for food and feed are subject to European Union regulations. Compliance with the regulations requires the targeting of, among others, the agroclimatic factors influencing fungal contamination and FUMO production. Arvalis-Institut du végétal has created a national, multiyear database for maize, based on field survey data collected since 2003. This database contains information about agricultural practices, climatic conditions and FUMO concentrations at harvest for 738 maize fields distributed throughout French maize-growing regions. A linear mixed model approach highlights the presence of borers and the use of a late variety, high temperatures in July and October, and a water deficit during the maize cycle as creating conditions favoring maize contamination with Fusarium verticillioides. It is thus possible to target a combination of risk factors, consisting of this climatic sequence associated with agricultural practices of interest. The effects of the various possible agroclimatic combinations can be compared, grouped and classified as promoting very low to high FUMO concentrations, possibly exceeding the regulatory threshold. These findings should facilitate the creation of a national, informative and easy-to-use prevention tool for producers and agricultural cooperatives to manage the sanitary quality of their harvest.


Assuntos
Clima , Proteção de Cultivos , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos , Fumonisinas/análise , Fusarium/metabolismo , Zea mays/microbiologia , Irrigação Agrícola , Bases de Dados Factuais , França , Fumonisinas/toxicidade , Fusarium/crescimento & desenvolvimento , Estado de Hidratação do Organismo , Medição de Risco , Fatores de Risco , Temperatura , Fatores de Tempo
3.
J Hazard Mater ; 401: 123131, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32763672

RESUMO

Contamination of durum wheat grain by cadmium (Cd) threatens food safety and is of increasing concern because regulations concerning Cd are becoming stricter due to its toxicity. This work aimed at using soil variables and cultivar types to build models to predict whether durum wheat grain Cd will conform with current and possibly lower regulatory thresholds. We combined multiple Gaussian and logistic regressions and the random forest algorithm to take advantage of their strength. Models tested using cross-validation produced excellent performances including for the lowest regulatory threshold of 0.1 mg Cd/kg, half of the current one: 79-85% of the non-conformity cases were detected and the reliability of predictions was 69-82%. The models enabled identification of a x1.4 variability in grain Cd content between cultivars that do not have the low Cd accumulation allele of the Cdu1 gene. The models confirmed that for the grain Cd content, the between-cultivar variability had much less influence than the phytoavailability of Cd in soil, the critical contexts of which were characterized by the models. For farmers, these models are valuable tools to predict whether durum wheat production will conform with existing and future Cd regulation in foodstuffs.


Assuntos
Cádmio , Poluentes do Solo , Cádmio/análise , Grão Comestível/química , Reprodutibilidade dos Testes , Solo , Poluentes do Solo/análise , Triticum/genética
4.
Sci Rep ; 10(1): 12234, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699344

RESUMO

Despite the large morphological and physiological changes that plants have undergone through domestication, little is known about their impact on their microbiome. Here we characterized rhizospheric bacterial and fungal communities as well as the abundance of N-cycling microbial guilds across thirty-nine accessions of tetraploid wheat, Triticum turgidum, from four domestication groups ranging from the wild subspecies to the semi dwarf elite cultivars. We identified several microbial phylotypes displaying significant variation in their relative abundance depending on the wheat domestication group with a stronger impact of domestication on fungi. The relative abundance of potential fungal plant pathogens belonging to the Sordariomycetes class decreased in domesticated compared to wild emmer while the opposite was found for members of the Glomeromycetes, which are obligate plant symbionts. The depletion of nitrifiers and of arbuscular mycorrhizal fungi in elite wheat cultivars compared to primitive domesticated forms suggests that the Green Revolution has decreased the coupling between plant and rhizosphere microbes that are potentially important for plant nutrient availability. Both plant diameter and fine root percentage exhibited the highest number of associations with microbial taxa, highlighting their putative role in shaping the rhizosphere microbiota during domestication. Aside from domestication, significant variation of bacterial and fungal community composition was found among accessions within each domestication group. In particular, the relative abundances of Ophiostomataceae and of Rhizobiales were strongly dependent on the host accession, with heritability estimates of ~ 27% and ~ 25%, indicating that there might be room for genetic improvement via introgression of ancestral plant rhizosphere-beneficial microbe associations.


Assuntos
Bactérias/genética , Domesticação , Microbiota/genética , Micobioma/genética , Micorrizas/genética , Raízes de Plantas/microbiologia , Triticum/microbiologia , Genótipo , Fenótipo , Rizosfera , Microbiologia do Solo , Tetraploidia
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