Search results for "Tillage"

Differential Responses of Nitrate Reducer Community Size, Structure, and Activity to Tillage Systems

2009

ABSTRACT The main objective of this study was to determine how the size, structure, and activity of the nitrate reducer community were affected by adoption of a conservative tillage system as an alternative to conventional tillage. The experimental field, established in Madagascar in 1991, consists of plots subjected to conventional tillage or direct-seeding mulch-based cropping systems (DM), both amended with three different fertilization regimes. Comparisons of size, structure, and activity of the nitrate reducer community in samples collected from the top layer in 2005 and 2006 revealed that all characteristics of this functional community were affected by the tillage system, with increa…

Comparison of different tillage systems in organic farming : effect of soil structure and organic matter repartition on soil micro-organisms and thei…

2009

Over the last decades, the surface traditionally ploughed has tended to decrease and replaced by shallow working tillage techniques without soil inversion, i.e., no tillage or reduced tillage with tines or discs. These techniques were mostly developed in conventional farming systems but nowadays they are also developed in organic farming systems. Nevertheless, these tillage techniques could generate crop nutrients deficiencies and a deterioration of soil structure, especially during the first years of their application. As the use of synthetic fertilizers is forbidden in organic farming, a decrease of the soil fertility could be very detrimental for crop growth. Indeed, soil micro-organisms…

Et si une impasse de désherbage en agriculture de conservation des sols vous poussait à retravailler le sol ? Quelle intervention choisiriez-vous ?

2019

National audience; En Agriculture de Conservation des Sols (ACS), la perturbation minimale du sol est l’un des trois prin-cipes. Si l’impasse se fait sentir mieux vaut repenser le système que de laisser le mur se rapprocher à grands pas. Trois types de gestion d’interculture (Labour, travail superficiel (TCS) et semis direct avec glyphosate (SD)) ont été comparés sur des parcelles conduites sans labour depuis 17 ans dont les 7 dernières années en ACS sur le domaine de l’INRA de Dijon avant implantation d’un blé, sur un dispo-sitif en bandes répétées sur quatre parcelles. Des relevés de flore adventice, rendement et compo-sante de rendement ont été faite. Les densités moyennes sont faibles p…

Weed communities in conservation agriculture: what really changes?

2022

Conservation agriculture (CA) has been identified as one of the farming systems likely to deliver sustainable agriculture but its effects over time on the diversity and composition of weed communities are still discussed. For ten years, different studies were carried out in in East of France in cropping system with short rotations essentially composed with winter crops. The objective of these different studies was to identify, focusing on the transition period, the changes in the composition of communities and the consequences in terms of agronomic risk in CA systems. Using networks of 100 winter wheat fields selected to encompass a gradient of years in CA (1 to 20 years), the changes that …

Assessing non-chemical weeding strategies through mechanistic modelling of blackgrass (Alopecurus myosuroides Huds.) dynamics

2010

 ; Because of environmental and health safety issues, it is necessary to develop strategies that do not rely on herbicides to manage weeds. Introducing temporary grassland into annual crop rotations and mechanical weeding are the two main features that are frequently used in integrated and organic cropping systems for this purpose. To evaluate the contribution of these two factors in interaction with other cropping system components and environmental conditions, the present study updated an existing biophysical model (i.e. AlomySys) that quantifies the effects of cropping system on weed dynamics. Based on previous experiments, new sub-models were built to describe the effects on plant survi…

Ecological role of mycotoxins produced by Fusarium graminearum : consequences of the presence of deoxynivalenol (DON) in crop residues on the soil mi…

2012

Fusarium graminearum is a plant pathogenic fungus, causing devastating disease “Fusarium head blight” (FHB) in cereals including wheat and maize. It also contaminates the grains with mycotoxins including deoxynivalenol (DON) which are toxic to human and animals. This disease has resulted in the serious losses in grain yield and quality. We established through a first bibliographic review that during off season fungus survives saprophytically on the crop residues (ecological habitat) and serves as primary inoculum for the next season crop. However, we noticed also that the literature was poor about the role mycotoxins could play in the establishment of F. graminearum in such a habitat. The m…

Etude de la variabilité des propriétés physiques et hydrodynamiques d'un sol argileux sous l'effet de conduites en protection intégrée contre les adv…

2015

Integrated weed management (IWM)-based cropping systems are of great interest due to their significant reduction of herbicide inputs by using a complex combination of agricultural techniques. The main objective of our work was to contribute to the environmental dimension of the multi-criteria evaluation of IWM-based cropping systems which were set up since 2000 on the experimental domain of the National Institute for Agronomical Research (INRA) to Bretenière (France). The variability of physical and hydrodynamic soil properties involved in the transfer of water through the vadose zone was studied for the 5 cropping systems present on the experimental site (1 reference cropping system and 4 …

Transition to conservation agriculture : changes in cropping practices and responses of weed communities

2020

Conservation agriculture is a farming system based on the continuous and simultaneous application of three principles: minimal soil disturbance, continuous residue cover on the soil surface and diverse crop rotations. Adoption of this form of sustainable agriculture in France since the 2000s has been hampered by a number of constraints, including the development and management of weed populations. From an agronomic point of view, the adoption of conservation agriculture and associated abandonment of tillage results in a significant loss of weed management practices for farmers. From an ecological point of view, its application can modify all the assembly processes that act on weed communiti…

Impact of fertilization, tillage and direct seeding on nitrate reducers in Madagascar

2007

Weed flora evolution in direct seeding under cover systems

2018

Direct seeding under cover, by its emergent properties, raises new questions of research on weed communities. The absence of soil disturbance and the implementation of cover crops, modify all factors of conventional agriculture and lead to a complete change of habitat for and management of the weed flora. In addition, these systems allow the development of a certain number of animal communities that interact with one another and with plant communities and thus potentially promote the regulations expected in Agroecology. Finally, there is the issue of annual weed species diversity in systems where tillage is strongly reduced. This thesis, started in November 2017, has as main objective to pr…