Consulta: creatorFacets:"Jeuffroy, Marie-Hélène"
Registros recuperados: 7
Data/hora: 12/06/2024 05:08:48

Indicators of weed competition on Organic Winter Wheat
Provedor de dados: 21
Autores: Casagrande, Marion; David, Christophe; Valentin Morison, Muriel; Jeuffroy, Marie-Hélène.
Organic winter wheat production is limited by climatic and agronomic factors, including weed competition. The incidence of weeds on yield limitation can be characterized through various early indicators to predict weed occurrence and competition. A network of 10 fields of organic winter wheat was implemented in the South East of France in 2005-2006. Results showed that weed density, dynamics and diversity are good indicators for weed occurrence and competition.
Tipo: Conference paper, poster, etc.
Palavras-chave: Cereals; Pulses and oilseeds Weed management.
Ano: 2007
URL: http://orgprints.org/10311/1/casagrande%2Detal%2D2007%2Dwinterwheat.pdf

Incidence of limiting factors on organic winter wheat performance
Provedor de dados: 21
Autores: Casagrande, Marion; David, Christophe; Valantin-Morison, Muriel; Jeuffroy, Marie-Hélène.
French organic farmers are asked to increase Grain Protein Content (GPC) of organic winter wheat to guarantee the breadmaking quality required from millers. Facing with the recent depletion of organic products, farmers also need to stabilize and increase the yield performance. The aim of our study is to give the explanations of the yield and GPC variability generally observed in organic production. A diagnostic method will be implemented on a network of ca. 10 fields per year during two crop years added with previous field network (77 fields) and experi-ments (4 experiments on cultivars). We will under-stand yield and GPC performance from environmental and agronomic conditions  and relate the observed limiting factors with crop management, climatic...
Tipo: Conference paper, poster, etc.
Palavras-chave: Cereals; Pulses and oilseeds.
Ano: 2006
URL: http://orgprints.org/7358/1/ShortpaperMarionCasagrande.rtf

A sequential approach for improving AZODYN crop model under conventional and low-input conditions
Provedor de dados: 21
Autores: David, Christophe; Jeuffroy, Marie-Hélène.
Advances in scientific understanding of the plant and soil behaviour in a cultivated field led to the design of numerous soil-crop models simulating crop growth. The frequent low predictive quality of these models is linked to uncertainties in inputs, parameters and equations. The AZODYN crop model predicting wheat grain yield and grain protein content was previously developed to support decision for N management of conventional and organic wheat crops. This paper outlines a sequential approach to improve the predictions of the AZODYN model by testing various formalisms. This study is based on the comparison of 38 versions of the model assessed in multi-environment trials carried out under conventional or low-input conditions. This paper describes and...
Tipo: Journal paper
Palavras-chave: Cereals; Pulses and oilseeds Composting and manuring Nutrient turnover.
Ano: 2009
URL: http://orgprints.org/19494/1/David_et_Jeuffroy%2C_2009.pdf

Wheat/forage legume intercropping in organic grain system: an answer to both weed and nitrogen deficiency issues
Provedor de dados: 21
Autores: Amosse, Camille; Celette, Florian; Jeuffroy, Marie-Hélène; David, Christophe.
Organic grain system managers have to find solutions to nitrogen deficiency and weed infestation. It is especially true when no animals are present on the farm to justify the use of forage legumes despite their interests in the crop succession. Our study focused on the role of four legume cover crop species inserted in a succession of winter wheat and maize on both problems. This insertion consisted in relay-intercropping the legumes under the canopy of wheat. Cover crops were maintained on the field after the harvest of the cereal until the sowing of the subsequent maize crop. The performance of the three crops of the succession was monitored as well as weed development and nitrogen dynamic in the soil-plant system. On the one hand, our results showed...
Tipo: Journal paper
Palavras-chave: Crop combinations and interactions Crop health; Quality; Protection Weed management.
Ano: 2013
URL: http://orgprints.org/26014/1/Amosse_2013_CIAG_Vol32.pdf

Agronomic and environmental factors explaining Grain Protein Content variability in organic winter wheat
Provedor de dados: 21
Autores: Casagrande, Marion; David, Christophe; Etienne, Catherine; Makowski, David; Valantin-Morison, Muriel; Jeuffroy, Marie-Hélène.
A regional agronomic diagnosis was implemented to identify factors responsible for low values of Grain Protein Content (GPC) in a network of 35 organic winter wheat fields in South-Eastern France. The influence of water nutrition, radiation and temperature, weed density at flowering, nitrogen (N) status of crop at flowering and variety type were studied. Two statistical methods were used successively: classical linear regression and a mixing model approach based on a weighted sum of all possible linear combinations of explanatory variables. GPC was significantly related to variety type, crop N status and weed density. An analysis of variance showed that weed density was related to soil type and nitrogen supply.
Tipo: Conference paper, poster, etc.
Palavras-chave: Cereals; Pulses and oilseeds.
Ano: 2008
URL: http://orgprints.org/11825/1/Casagrande_11825_ed.doc

Improvement of the soil-crop model AZODYN under conventional, low-input and organic conditions
Provedor de dados: 21
Autores: David, Christophe; Jeuffroy, Marie-Hélène; Valentin Morison, Muriel; Herbain, Céline.
The use of mechanistic crop modelling, simulating the dynamics of crop N requirements and nitrogen supply from the soil and fertilizers, can provide sound advice to users. This paper describes a methodological way to improve soil-crop modeling used for N management of conventional and organic wheat.
Tipo: Conference paper, poster, etc.
Palavras-chave: Cereals; Pulses and oilseeds Farm nutrient management Composting and manuring.
Ano: 2007
URL: http://orgprints.org/10310/1/david%2Detal%2D2007%2Dsoil%2Dcrop%2Dmodel_azodyn.pdf

Factors limiting the grain protein content of organic winter wheat in south-eastern France: a mixed-model approach.
Provedor de dados: 21
Autores: Casagrande, Marion; David, Christophe; Valantin-Morison, Muriel; Makowski, David; Jeuffroy, Marie-Hélène.
Organic agriculture could achieve the objectives of sustainable agriculture by banning the use of synthetic fertilizers and pesticides. However, organic crops generally show lower performances than conventional ones. In France, organic winter wheat production is characterized by low grain protein content. There is a crucial need for better understanding the variability of grain protein content, because millers require batches with values over 10.5% of dry matter. Here, a regional agronomic diagnosis was carried out to identify the limiting factors and crop management practices explaining the variability of grain protein content. The studied field network was a set of 51 organic winter wheat plots in south-eastern France. The mixed-model method was used for...
Tipo: Journal paper
Palavras-chave: Soil Crop health; Quality; Protection Produce chain management.
Ano: 2009
URL: http://orgprints.org/22523/1/Casagrande_2012_%2322523_Journal%20Paper.pdf